chore: merge develop while preserving console interactions

Cargo.lock

@@ -6383,6 +6383,7 @@ dependencies = [
 name = "yoi-workspace-server"
 version = "0.1.0"
 dependencies = [
+ "agen",
  "async-trait",
  "axum",
  "chrono",
@@ -6410,6 +6411,7 @@ dependencies = [
  "tokio",
  "tokio-tungstenite 0.29.0",
  "toml",
+ "tools",
  "tower",
  "tracing",
  "tracing-subscriber",
@@ -6421,6 +6423,7 @@ dependencies = [
  "workdir",
  "worker",
  "worker-runtime",
+ "yoi",
  "zeroize",
 ]
 

crates/fs-operation/src/lib.rs

@@ -15,7 +15,8 @@ use thiserror::Error;
 
 pub use glob::run_glob;
 pub use local::{
-    resolve_access_path, run_edit, run_list, run_read, run_read_bounded, run_stat, run_write,
+    resolve_access_path, run_edit, run_list, run_read, run_read_bounded, run_read_bytes,
+    run_read_bytes_bounded, run_stat, run_write,
 };
 pub use operation::*;
 pub use search::run_grep;
@@ -569,6 +570,103 @@ mod tests {
         }
     }
 
+    #[test]
+    fn bounded_byte_reads_preserve_binary_ranges_and_fence_versions() {
+        let directory = tempfile::tempdir().unwrap();
+        let root = directory.path().canonicalize().unwrap();
+        let original = b"\x89PNG\r\n\x1a\n\0line\n\xfftail";
+        std::fs::write(root.join("image.bin"), original).unwrap();
+        let access = RootAccess(root.clone());
+        let limits = BoundedReadLimits::new(1024, 8).unwrap();
+
+        let first = run_read_bytes_bounded(
+            &root,
+            ReadBytesRequest {
+                path: FsPath::new("image.bin").unwrap(),
+                offset: 0,
+                max_bytes: 8,
+                expected_hash: None,
+            },
+            &access,
+            limits,
+        )
+        .unwrap();
+        assert_eq!(first.bytes, original[..8]);
+        assert_eq!(first.total_bytes, original.len() as u64);
+        assert!(!first.eof);
+
+        let second = run_read_bytes_bounded(
+            &root,
+            ReadBytesRequest {
+                path: FsPath::new("image.bin").unwrap(),
+                offset: 8,
+                max_bytes: 8,
+                expected_hash: Some(first.content_hash),
+            },
+            &access,
+            limits,
+        )
+        .unwrap();
+        assert_eq!(second.bytes, original[8..16]);
+        assert_eq!(second.content_hash, first.content_hash);
+
+        std::fs::write(root.join("image.bin"), b"different bytes long!").unwrap();
+        let error = run_read_bytes_bounded(
+            &root,
+            ReadBytesRequest {
+                path: FsPath::new("image.bin").unwrap(),
+                offset: 16,
+                max_bytes: 8,
+                expected_hash: Some(first.content_hash),
+            },
+            &access,
+            limits,
+        )
+        .expect_err("a later chunk must not cross file versions");
+        assert!(matches!(error, FsError::Conflict(_)));
+    }
+
+    #[test]
+    fn bounded_byte_reads_reject_request_and_source_limit_overflow() {
+        let directory = tempfile::tempdir().unwrap();
+        let root = directory.path().canonicalize().unwrap();
+        std::fs::write(root.join("image.bin"), [0_u8; 17]).unwrap();
+        let access = RootAccess(root.clone());
+        let limits = BoundedReadLimits::new(16, 8).unwrap();
+
+        let response_error = run_read_bytes_bounded(
+            &root,
+            ReadBytesRequest {
+                path: FsPath::new("image.bin").unwrap(),
+                offset: 0,
+                max_bytes: 9,
+                expected_hash: None,
+            },
+            &access,
+            limits,
+        )
+        .expect_err("requests above the response ceiling must be rejected");
+        assert!(
+            matches!(response_error, FsError::InvalidArgument(message) if message.contains("8 bytes"))
+        );
+
+        let source_error = run_read_bytes_bounded(
+            &root,
+            ReadBytesRequest {
+                path: FsPath::new("image.bin").unwrap(),
+                offset: 0,
+                max_bytes: 8,
+                expected_hash: None,
+            },
+            &access,
+            limits,
+        )
+        .expect_err("sources above the provider ceiling must be rejected");
+        assert!(
+            matches!(source_error, FsError::InvalidArgument(message) if message.contains("provider limit 16"))
+        );
+    }
+
     #[test]
     fn cancellation_stops_a_read_already_in_progress() {
         use std::sync::atomic::{AtomicBool, AtomicUsize, Ordering};

crates/fs-operation/src/local.rs

@@ -7,8 +7,9 @@ use sha2::{Digest, Sha256};
 
 use crate::{
     AtomicWriteMode, BoundedReadLimits, ContentHash, EditRequest, EditResult, EntryKind,
-    FsAccessPolicy, FsError, FsPath, ListEntry, ListRequest, ListResult, ReadRequest, ReadResult,
-    StatRequest, StatResult, WriteRequest, WriteResult, direct_symlink,
+    FsAccessPolicy, FsError, FsPath, ListEntry, ListRequest, ListResult, ReadBytesRequest,
+    ReadBytesResult, ReadRequest, ReadResult, StatRequest, StatResult, WriteRequest, WriteResult,
+    direct_symlink,
 };
 
 const READ_BUFFER_BYTES: usize = 16 * 1024;
@@ -195,6 +196,137 @@ fn run_read_with_limits(
     })
 }
 
+pub fn run_read_bytes(
+    root: &Path,
+    request: ReadBytesRequest,
+    access: &dyn FsAccessPolicy,
+) -> Result<ReadBytesResult, FsError> {
+    run_read_bytes_with_limits(root, request, access, None)
+}
+
+pub fn run_read_bytes_bounded(
+    root: &Path,
+    request: ReadBytesRequest,
+    access: &dyn FsAccessPolicy,
+    limits: BoundedReadLimits,
+) -> Result<ReadBytesResult, FsError> {
+    run_read_bytes_with_limits(root, request, access, Some(limits))
+}
+
+fn run_read_bytes_with_limits(
+    root: &Path,
+    request: ReadBytesRequest,
+    access: &dyn FsAccessPolicy,
+    limits: Option<BoundedReadLimits>,
+) -> Result<ReadBytesResult, FsError> {
+    let logical = request.path;
+    if request.max_bytes == 0 {
+        return Err(FsError::InvalidArgument(
+            "byte read max_bytes must be greater than zero".to_string(),
+        ));
+    }
+    if let Some(limits) = limits
+        && request.max_bytes > limits.max_response_bytes
+    {
+        return Err(FsError::InvalidArgument(format!(
+            "byte read response limit is {} bytes",
+            limits.max_response_bytes
+        )));
+    }
+
+    access
+        .check_cancelled()
+        .map_err(|error| map_io(&logical, error))?;
+    let path = resolve(root, &logical)?;
+    let target = require_access(&path, &logical, access, false, false)?;
+    let file = access
+        .open_read_file(&path, &target)
+        .map_err(|error| map_io(&logical, error))?;
+    let metadata = file.metadata().map_err(|error| map_io(&logical, error))?;
+    if metadata.is_dir() {
+        return Err(FsError::IsDirectory(PathBuf::from(logical.as_str())));
+    }
+    if !metadata.is_file() {
+        return Err(FsError::InvalidArgument(
+            "byte read source must be a regular file".to_string(),
+        ));
+    }
+    if let Some(limits) = limits
+        && metadata.len() > limits.max_source_bytes
+    {
+        return Err(FsError::InvalidArgument(format!(
+            "byte read source exceeds provider limit {}",
+            limits.max_source_bytes
+        )));
+    }
+
+    let mut bytes = Vec::with_capacity(request.max_bytes.min(READ_BUFFER_BYTES));
+    let mut source_bytes = 0_u64;
+    let mut hasher = Sha256::new();
+    let mut reader = BufReader::with_capacity(READ_BUFFER_BYTES, file);
+    let mut buffer = [0_u8; READ_BUFFER_BYTES];
+    loop {
+        access
+            .check_cancelled()
+            .map_err(|error| map_io(&logical, error))?;
+        let read_limit = limits
+            .map(|limits| {
+                limits
+                    .max_source_bytes
+                    .saturating_sub(source_bytes)
+                    .saturating_add(1)
+                    .min(READ_BUFFER_BYTES as u64) as usize
+            })
+            .unwrap_or(READ_BUFFER_BYTES);
+        let read = reader
+            .read(&mut buffer[..read_limit])
+            .map_err(|error| map_io(&logical, error))?;
+        if read == 0 {
+            break;
+        }
+        let chunk_start = source_bytes;
+        source_bytes = source_bytes.saturating_add(read as u64);
+        if let Some(limits) = limits
+            && source_bytes > limits.max_source_bytes
+        {
+            return Err(FsError::InvalidArgument(format!(
+                "byte read source exceeds provider limit {}",
+                limits.max_source_bytes
+            )));
+        }
+        hasher.update(&buffer[..read]);
+
+        if bytes.len() < request.max_bytes && source_bytes > request.offset {
+            let start = request.offset.saturating_sub(chunk_start).min(read as u64) as usize;
+            let retained = (request.max_bytes - bytes.len()).min(read - start);
+            bytes.extend_from_slice(&buffer[start..start + retained]);
+        }
+    }
+
+    let content_hash: ContentHash = hasher.finalize().into();
+    if request
+        .expected_hash
+        .is_some_and(|expected| expected != content_hash)
+    {
+        return Err(FsError::Conflict(logical.as_str().to_string()));
+    }
+    if request.offset > source_bytes {
+        return Err(FsError::InvalidArgument(format!(
+            "byte offset {} exceeds file size {source_bytes}",
+            request.offset
+        )));
+    }
+    let eof = request.offset.saturating_add(bytes.len() as u64) == source_bytes;
+    Ok(ReadBytesResult {
+        path: logical,
+        bytes,
+        offset: request.offset,
+        total_bytes: source_bytes,
+        content_hash,
+        eof,
+    })
+}
+
 pub fn run_write(
     root: &Path,
     request: WriteRequest,

crates/fs-operation/src/operation.rs

@@ -207,6 +207,36 @@ pub struct ReadResult {
     pub truncated: bool,
 }
 
+/// Binary-safe byte range read with an optional whole-file version fence.
+///
+/// Unlike [`ReadRequest`], offsets and limits are bytes rather than lines. The
+/// provider still hashes the complete bounded source so callers can reject
+/// chunks from different file versions.
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
+#[serde(deny_unknown_fields)]
+pub struct ReadBytesRequest {
+    pub path: FsPath,
+    #[schemars(range(min = 0, max = 9_007_199_254_740_991_u64))]
+    pub offset: u64,
+    #[schemars(range(min = 1, max = 9_007_199_254_740_991_usize))]
+    pub max_bytes: usize,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub expected_hash: Option<ContentHash>,
+}
+
+#[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
+#[serde(deny_unknown_fields)]
+pub struct ReadBytesResult {
+    pub path: FsPath,
+    pub bytes: Vec<u8>,
+    #[schemars(range(min = 0, max = 9_007_199_254_740_991_u64))]
+    pub offset: u64,
+    #[schemars(range(min = 0, max = 9_007_199_254_740_991_u64))]
+    pub total_bytes: u64,
+    pub content_hash: ContentHash,
+    pub eof: bool,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize, JsonSchema)]
 #[serde(deny_unknown_fields)]
 pub struct WriteRequest {

crates/protocol/src/lib.rs

@@ -838,6 +838,56 @@ pub struct SessionSnapshot {
     pub entries: Vec<SessionSnapshotEntry>,
 }
 
+/// One user-visible conversation turn. A turn starts at a canonical user entry
+/// and contains every public committed entry until the next user entry.
+/// `turn_id` is the stable `entry_id` of that first user entry.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[cfg_attr(feature = "typescript", derive(ts_rs::TS))]
+#[cfg_attr(feature = "json-schema", derive(schemars::JsonSchema))]
+pub struct SessionConversationTurn {
+    pub turn_id: String,
+    pub entries: Vec<SessionSnapshotEntry>,
+}
+
+/// The immediate parent lineage and the stable real-user boundary adopted from it.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[cfg_attr(feature = "typescript", derive(ts_rs::TS))]
+#[cfg_attr(feature = "json-schema", derive(schemars::JsonSchema))]
+pub struct SessionHistoryLineageBoundary {
+    pub lineage_id: String,
+    /// Canonical public form of the final user-visible turn at the exact
+    /// provider boundary. Entries after that boundary are excluded.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub adopted_through_turn: Option<SessionConversationTurn>,
+}
+
+/// Bounded backward page over the adopted conversation lineage.
+///
+/// Turns remain chronological within a page. `next_cursor` is an opaque,
+/// identity-bound boundary for the page immediately preceding `turns`.
+#[derive(Debug, Clone, PartialEq, Serialize, Deserialize)]
+#[cfg_attr(feature = "typescript", derive(ts_rs::TS))]
+#[cfg_attr(feature = "json-schema", derive(schemars::JsonSchema))]
+pub struct SessionHistoryPage {
+    pub session_id: String,
+    /// Stable identity of the adopted active lineage used to fence stale pages.
+    pub lineage_id: String,
+    /// Older lineage identities that the active lineage fully adopted through
+    /// one or more consecutive Compact rotations. Clients may retain already
+    /// loaded turns when their prior lineage appears here, while replacing the
+    /// cursor with this page's boundary.
+    #[serde(default, skip_serializing_if = "Vec::is_empty")]
+    pub compact_ancestor_lineage_ids: Vec<String>,
+    /// Immediate parent relationship used to retain only the adopted prefix
+    /// across fork/rewind refreshes that have no newest-page overlap.
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub parent_lineage: Option<SessionHistoryLineageBoundary>,
+    pub turns: Vec<SessionConversationTurn>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub next_cursor: Option<String>,
+    pub has_more: bool,
+}
+
 #[derive(Debug, Clone, PartialEq, Eq, Serialize, Deserialize)]
 #[cfg_attr(feature = "typescript", derive(ts_rs::TS))]
 #[cfg_attr(feature = "json-schema", derive(schemars::JsonSchema))]
@@ -963,8 +1013,17 @@ pub enum Event {
     /// activated for a turn. Broadcast to every subscribed client so TUI / GUI
     /// instances show the same user line that reconnect snapshots replay.
     UserMessage {
+        /// Stable durable history identity. Older mixed-version producers omit it.
+        #[serde(default, skip_serializing_if = "Option::is_none")]
+        entry_id: Option<String>,
         segments: Vec<Segment>,
     },
+    /// A canonical assistant/tool entry has committed to durable history.
+    /// Streaming events remain the in-flight authority; this event supplies the
+    /// stable identity used to reconcile that live block with paged history.
+    SessionEntryCommitted {
+        entry: SessionSnapshotEntry,
+    },
     /// One agent-injected system item committed to history.
     ///
     /// Carries the JSON form of `session_store::SystemItem`. Covers
@@ -2765,6 +2824,7 @@ mod tests {
     #[test]
     fn event_user_message_roundtrip() {
         let event = Event::UserMessage {
+            entry_id: Some("entry-1".to_string()),
             segments: vec![Segment::text("hello 世界")],
         };
         let json = serde_json::to_string(&event).unwrap();
@@ -2775,7 +2835,7 @@ mod tests {
 
         let decoded: Event = serde_json::from_str(&json).unwrap();
         match decoded {
-            Event::UserMessage { segments } => {
+            Event::UserMessage { segments, .. } => {
                 assert_eq!(segments.len(), 1);
                 match &segments[0] {
                     Segment::Text { content } => assert_eq!(content, "hello 世界"),

crates/protocol/src/typescript.rs

@@ -11,12 +11,13 @@ use crate::{
     InternalWorkerRef, InternalWorkerSnapshot, InvokeKind, MemoryWorkerEvent, Method,
     PasteArtifactAvailability, PasteArtifactMediaType, PasteArtifactRef, PendingSubmissionSummary,
     PendingSubmissionsSnapshot, Permission, RewindSummary, RewindTarget, RewindTargetId, RunResult,
-    ScopeRule, Segment, SessionContentPart, SessionEntryProvenance, SessionMessageRole,
-    SessionSnapshot, SessionSnapshotEntry, SessionSnapshotEntryData, SessionToolAttachment,
-    SubmissionDisposition, SymlinkPolicy, ToolResultDisposition, TurnResult,
-    UploadedFileAvailability, UploadedFileRef, WorkerBusyState, WorkerCommandAcknowledgement,
-    WorkerCommandDisposition, WorkerCommandEnvelope, WorkerCommandKind, WorkerEvent,
-    WorkerMaintenanceState, WorkerRunState, WorkerState, WorkerStateSnapshot, WorkerStatus,
+    ScopeRule, Segment, SessionContentPart, SessionConversationTurn, SessionEntryProvenance,
+    SessionHistoryLineageBoundary, SessionHistoryPage, SessionMessageRole, SessionSnapshot,
+    SessionSnapshotEntry, SessionSnapshotEntryData, SessionToolAttachment, SubmissionDisposition,
+    SymlinkPolicy, ToolResultDisposition, TurnResult, UploadedFileAvailability, UploadedFileRef,
+    WorkerBusyState, WorkerCommandAcknowledgement, WorkerCommandDisposition, WorkerCommandEnvelope,
+    WorkerCommandKind, WorkerEvent, WorkerMaintenanceState, WorkerRunState, WorkerState,
+    WorkerStateSnapshot, WorkerStatus,
     subscription::{
         EventSubscriptionSelector, MAX_CORRELATION_ID_BYTES, MAX_REJECTION_MESSAGE_BYTES,
         MAX_RESOURCE_ID_BYTES, MAX_SUBSCRIPTION_COLLECTION_ITEMS,
@@ -104,6 +105,9 @@ pub fn generated_protocol_types() -> String {
     push_decl::<SessionToolAttachment>(&cfg, &mut output);
     push_decl::<SessionSnapshotEntryData>(&cfg, &mut output);
     push_decl::<SessionSnapshotEntry>(&cfg, &mut output);
+    push_decl::<SessionConversationTurn>(&cfg, &mut output);
+    push_decl::<SessionHistoryLineageBoundary>(&cfg, &mut output);
+    push_decl::<SessionHistoryPage>(&cfg, &mut output);
     push_decl::<PendingSubmissionSummary>(&cfg, &mut output);
     push_decl::<PendingSubmissionsSnapshot>(&cfg, &mut output);
     push_decl::<SubmissionDisposition>(&cfg, &mut output);

crates/runtime-api/src/lib.rs

@@ -655,6 +655,41 @@ pub struct WorkerSessionRequest {
     pub workspace_id: String,
 }
 
+#[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
+pub struct WorkerSessionHistoryRequest {
+    pub workspace_id: String,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub cursor: Option<String>,
+    #[serde(default, skip_serializing_if = "Option::is_none")]
+    pub limit: Option<usize>,
+}
+
+#[derive(Clone, Copy, Debug, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(rename_all = "snake_case")]
+pub enum WorkerSessionHistoryUnavailableReason {
+    RetentionMissing,
+    ActivePointerMissing,
+    CorruptLog,
+    MigrationRequired,
+    RetentionExpired,
+    StorageUnavailable,
+    InvalidCursor,
+    ResourceLimit,
+    Unsupported,
+}
+
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+#[serde(tag = "availability", rename_all = "snake_case")]
+pub enum WorkerSessionHistoryAvailability {
+    Page {
+        page: protocol::SessionHistoryPage,
+    },
+    Unavailable {
+        reason: WorkerSessionHistoryUnavailableReason,
+        message: String,
+    },
+}
+
 #[derive(Clone, Debug, PartialEq, Eq, Serialize, Deserialize)]
 pub struct RetainedSessionIdentity {
     pub session_id: String,
@@ -718,6 +753,17 @@ pub trait RuntimeApi {
         #[query] request: WorkerSessionRequest,
     ) -> Result<WorkerSessionAvailability, RuntimeApiError>;
 
+    #[get(
+        "/v1/workers/{worker_id}/session/history",
+        status = 200,
+        error_status = 400
+    )]
+    async fn worker_session_history(
+        &self,
+        #[path] worker_id: String,
+        #[query] request: WorkerSessionHistoryRequest,
+    ) -> Result<WorkerSessionHistoryAvailability, RuntimeApiError>;
+
     #[post("/v1/workers", status = 200, error_status = 400)]
     async fn create_worker(
         &self,
@@ -1053,6 +1099,17 @@ mod tests {
             Ok(WorkerSessionAvailability::LiveProtocol)
         }
 
+        async fn worker_session_history(
+            &self,
+            _worker_id: String,
+            _request: WorkerSessionHistoryRequest,
+        ) -> Result<WorkerSessionHistoryAvailability, RuntimeApiError> {
+            Ok(WorkerSessionHistoryAvailability::Unavailable {
+                reason: WorkerSessionHistoryUnavailableReason::Unsupported,
+                message: "unsupported".to_string(),
+            })
+        }
+
         async fn create_worker(
             &self,
             _request: CreateWorkerRequest,
@@ -1174,10 +1231,22 @@ mod tests {
         assert_eq!(value["message"], "snapshot exceeds limit");
     }
 
+    #[test]
+    fn worker_session_history_availability_has_closed_tagged_wire_shape() {
+        let value = serde_json::to_value(WorkerSessionHistoryAvailability::Unavailable {
+            reason: WorkerSessionHistoryUnavailableReason::InvalidCursor,
+            message: "cursor is stale".to_string(),
+        })
+        .unwrap();
+        assert_eq!(value["availability"], "unavailable");
+        assert_eq!(value["reason"], "invalid_cursor");
+        assert_eq!(value["message"], "cursor is stale");
+    }
+
     #[test]
     fn contract_inventory_is_complete_and_unique() {
         let operations = RuntimeApiMetadata::OPERATIONS;
-        assert_eq!(operations.len(), 16);
+        assert_eq!(operations.len(), 17);
         let mut routes = operations
             .iter()
             .map(|operation| (format!("{:?}", operation.method), operation.path))

crates/server-api/src/lib.rs

@@ -389,6 +389,20 @@ pub struct WorkspaceWorkerSessionResponse {
     pub observation: runtime_api::WorkerSessionAvailability,
 }
 
+#[derive(Clone, Debug, Default, PartialEq, Eq, Serialize, Deserialize)]
+#[serde(deny_unknown_fields)]
+pub struct WorkspaceWorkerSessionHistoryQuery {
+    pub cursor: Option<String>,
+    pub limit: Option<usize>,
+}
+
+#[derive(Clone, Debug, PartialEq, Serialize, Deserialize)]
+pub struct WorkspaceWorkerSessionHistoryResponse {
+    pub subject: WorkspaceWorkerSubject,
+    #[serde(flatten)]
+    pub observation: runtime_api::WorkerSessionHistoryAvailability,
+}
+
 #[api(reqwest, axum, openapi)]
 pub trait ServerApi {
     #[get("/health", status = 200, error_status = 400)]
@@ -1141,6 +1155,20 @@ pub trait ServerApi {
         #[path] worker_id: String,
     ) -> Result<WorkspaceWorkerSessionResponse, ServerApiError>;
 
+    #[get(
+        "/api/w/{workspace_id}/runtimes/{runtime_id}/workers/{worker_id}/session/history",
+        status = 200,
+        error_status = 400,
+        openapi = false
+    )]
+    async fn worker_session_history(
+        &self,
+        #[path] workspace_id: String,
+        #[path] runtime_id: String,
+        #[path] worker_id: String,
+        #[query] query: WorkspaceWorkerSessionHistoryQuery,
+    ) -> Result<WorkspaceWorkerSessionHistoryResponse, ServerApiError>;
+
     #[get(
         "/api/workers",
         status = 200,
@@ -5262,27 +5290,71 @@ impl From<workdir::workspace::WorkingDirectorySummary> for WorkingDirectorySumma
     }
 }
 
+#[derive(Debug, Clone, Copy, PartialEq, Eq)]
+pub enum ExternalWorkdirPermissionLevel {
+    Read,
+    Write,
+    Command,
+}
+
+impl ExternalWorkdirPermissionLevel {
+    pub const fn permissions(self) -> ExternalWorkdirPermissions {
+        match self {
+            Self::Read => ExternalWorkdirPermissions::READ,
+            Self::Write => ExternalWorkdirPermissions::WRITE,
+            Self::Command => ExternalWorkdirPermissions::COMMAND,
+        }
+    }
+}
+
 #[derive(Debug, Clone, Copy, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
 #[cfg_attr(feature = "typescript", derive(ts_rs::TS))]
 #[serde(deny_unknown_fields)]
 pub struct ExternalWorkdirPermissions {
     /// Read files and use read-only discovery operations such as Glob and Grep.
+    /// Every supported External Workdir permission level enables this field.
     pub read: bool,
-    /// Create or update files with Write and Edit. Existing-file mutation also
-    /// requires `read` so callers can satisfy the read-before-write contract.
+    /// Create or update files with Write and Edit. WRITE includes READ so callers
+    /// can satisfy the read-before-write contract.
     pub write: bool,
-    /// Execute commands as the sharing CLI user on the provider host. This is
-    /// explicit authority and does not imply either filesystem category.
+    /// Execute commands as the sharing CLI user on the provider host. COMMAND
+    /// includes WRITE and READ, remains explicit, and is not sandboxed.
     pub command: bool,
 }
 
+impl ExternalWorkdirPermissions {
+    pub const READ: Self = Self {
+        read: true,
+        write: false,
+        command: false,
+    };
+    pub const WRITE: Self = Self {
+        read: true,
+        write: true,
+        command: false,
+    };
+    pub const COMMAND: Self = Self {
+        read: true,
+        write: true,
+        command: true,
+    };
+
+    /// Returns the single hierarchical level represented by a grant permission
+    /// object. Partial combinations remain valid for attachment/session
+    /// projections, but are not valid authority for creating an External grant.
+    pub const fn grant_level(self) -> Option<ExternalWorkdirPermissionLevel> {
+        match (self.read, self.write, self.command) {
+            (true, false, false) => Some(ExternalWorkdirPermissionLevel::Read),
+            (true, true, false) => Some(ExternalWorkdirPermissionLevel::Write),
+            (true, true, true) => Some(ExternalWorkdirPermissionLevel::Command),
+            _ => None,
+        }
+    }
+}
+
 impl Default for ExternalWorkdirPermissions {
     fn default() -> Self {
-        Self {
-            read: true,
-            write: false,
-            command: false,
-        }
+        Self::READ
     }
 }
 
@@ -11462,7 +11534,7 @@ mod openapi_artifact_tests {
         ];
         // Session observation retains its existing explicit non-OpenAPI boundary independently of
         // the Runtime/Worker-source signed operation inventory above.
-        const OTHER_OPENAPI_EXCLUDED: &[&str] = &["worker_session"];
+        const OTHER_OPENAPI_EXCLUDED: &[&str] = &["worker_session", "worker_session_history"];
         const DOCUMENTED_SIGNED_INTERNAL: &[&str] = &["workspace_runtime_config"];
         const BROWSER_ONLY: &[&str] = &["merge_request_selector_repair"];
 

crates/session-store/src/lib.rs

@@ -37,23 +37,31 @@ use std::path::Path;
 /// Read an existing retained file without updating its access timestamp.
 /// Observation fails closed when the platform cannot provide that guarantee.
 pub(crate) fn read_without_atime(path: &Path) -> io::Result<Vec<u8>> {
+    read_without_atime_bounded(path, u64::MAX)
+}
+
+/// Read at most `max_bytes + 1` retained bytes without updating access time.
+/// The extra byte lets callers prove that the authoritative file exceeded a
+/// limit without first racing a separate metadata length observation.
+pub(crate) fn read_without_atime_bounded(path: &Path, max_bytes: u64) -> io::Result<Vec<u8>> {
     #[cfg(any(target_os = "linux", target_os = "android"))]
     {
         use std::fs::OpenOptions;
         use std::io::Read;
         use std::os::unix::fs::OpenOptionsExt;
 
-        let mut file = OpenOptions::new()
+        let file = OpenOptions::new()
             .read(true)
             .custom_flags(libc::O_NOATIME)
             .open(path)?;
         let mut bytes = Vec::new();
-        file.read_to_end(&mut bytes)?;
+        file.take(max_bytes.saturating_add(1))
+            .read_to_end(&mut bytes)?;
         Ok(bytes)
     }
     #[cfg(not(any(target_os = "linux", target_os = "android")))]
     {
-        let _ = path;
+        let _ = (path, max_bytes);
         Err(io::Error::new(
             io::ErrorKind::Unsupported,
             "read-only retained observation requires no-atime file reads",
@@ -88,8 +96,12 @@ pub use history::{
 pub use logged_item::{LoggedContentPart, LoggedItem, LoggedRole, from_logged, to_logged};
 pub use paste_artifact::PasteArtifactLimits;
 pub use public_snapshot::{
-    DEFAULT_RETAINED_SNAPSHOT_MAX_BYTES, RetainedSessionIdentity, RetainedSessionSnapshot,
-    RetainedSnapshotReadError, project_session_snapshot, read_retained_session_snapshot,
+    DEFAULT_RETAINED_HISTORY_MAX_ENTRIES, DEFAULT_RETAINED_HISTORY_MAX_RESPONSE_BYTES,
+    DEFAULT_RETAINED_HISTORY_MAX_SCAN_BYTES, DEFAULT_RETAINED_HISTORY_MAX_SEGMENTS,
+    DEFAULT_RETAINED_HISTORY_PAGE_TURNS, DEFAULT_RETAINED_SNAPSHOT_MAX_BYTES,
+    MAX_RETAINED_HISTORY_PAGE_TURNS, RetainedHistoryReadError, RetainedHistoryReadLimits,
+    RetainedSessionIdentity, RetainedSessionSnapshot, RetainedSnapshotReadError,
+    project_session_snapshot, read_retained_session_history_page, read_retained_session_snapshot,
 };
 pub use segment::{
     SegmentStartState, append_entry, append_system_item, classify_logged_history_entry,

crates/session-store/src/store.rs

@@ -33,6 +33,9 @@ pub enum StoreError {
     #[error("log corrupted at line {line}: {message}")]
     Corrupt { line: usize, message: String },
 
+    #[error("retained observation read limit exceeded")]
+    ReadLimitExceeded,
+
     #[error("paste artifact storage is unavailable")]
     PasteArtifactUnsupported,
 

crates/session-store/src/worker_session_store.rs

@@ -25,7 +25,7 @@ use crate::{
 use protocol::{PasteArtifactRef, UploadedFileRef};
 use serde::{Deserialize, Serialize};
 use std::fs::{self, File, OpenOptions};
-use std::io::{Read, Seek, SeekFrom, Write};
+use std::io::{BufRead, BufReader, Read, Seek, SeekFrom, Write};
 use std::path::{Path, PathBuf};
 use std::sync::{Arc, Mutex};
 use std::time::SystemTime;
@@ -50,6 +50,106 @@ struct SessionManifest {
     session_id: SessionId,
 }
 
+const RETAINED_BACKWARD_READ_CHUNK_BYTES: usize = 64 * 1024;
+
+#[derive(Debug)]
+pub(crate) struct RetainedLogRecord {
+    pub start_offset: u64,
+    pub end_offset: u64,
+    pub entry: LogEntry,
+}
+
+pub(crate) struct RetainedSegmentReader {
+    file: File,
+    read_end: u64,
+    buffer_start: u64,
+    buffer: Vec<u8>,
+}
+
+impl RetainedSegmentReader {
+    pub fn previous_record(
+        &mut self,
+        max_additional_bytes: u64,
+    ) -> Result<(Option<RetainedLogRecord>, u64), StoreError> {
+        let mut read_bytes = 0_u64;
+        loop {
+            if !self.buffer.is_empty() {
+                if self.buffer.last() != Some(&b'\n') {
+                    return Err(StoreError::Corrupt {
+                        line: 0,
+                        message: "retained Segment cursor is not at a record boundary".to_string(),
+                    });
+                }
+                let prior_newline = self.buffer[..self.buffer.len() - 1]
+                    .iter()
+                    .rposition(|byte| *byte == b'\n');
+                if let Some(newline) =
+                    prior_newline.or((self.buffer_start == 0).then_some(usize::MAX))
+                {
+                    let record_start_in_buffer = if newline == usize::MAX {
+                        0
+                    } else {
+                        newline + 1
+                    };
+                    let record_start = self.buffer_start + record_start_in_buffer as u64;
+                    let record_end = self.buffer_start + self.buffer.len() as u64;
+                    let record =
+                        self.buffer[record_start_in_buffer..self.buffer.len() - 1].to_vec();
+                    self.buffer.truncate(record_start_in_buffer);
+                    self.read_end = record_start;
+                    if record.is_empty() {
+                        return Err(StoreError::Corrupt {
+                            line: 0,
+                            message: "empty retained Segment log record".to_string(),
+                        });
+                    }
+                    let entry = serde_json::from_slice(&record)?;
+                    return Ok((
+                        Some(RetainedLogRecord {
+                            start_offset: record_start,
+                            end_offset: record_end,
+                            entry,
+                        }),
+                        read_bytes,
+                    ));
+                }
+            } else if self.read_end == 0 {
+                return Ok((None, read_bytes));
+            }
+
+            if self.buffer_start == 0 && !self.buffer.is_empty() {
+                return Err(StoreError::Corrupt {
+                    line: 0,
+                    message: "retained Segment log does not end at a record boundary".to_string(),
+                });
+            }
+            if read_bytes >= max_additional_bytes {
+                return Err(StoreError::ReadLimitExceeded);
+            }
+            let end = if self.buffer.is_empty() {
+                self.read_end
+            } else {
+                self.buffer_start
+            };
+            let available = max_additional_bytes - read_bytes;
+            let chunk_len = end
+                .min(RETAINED_BACKWARD_READ_CHUNK_BYTES as u64)
+                .min(available);
+            if chunk_len == 0 {
+                return Err(StoreError::ReadLimitExceeded);
+            }
+            let start = end - chunk_len;
+            self.file.seek(SeekFrom::Start(start))?;
+            let mut chunk = vec![0_u8; chunk_len as usize];
+            self.file.read_exact(&mut chunk)?;
+            read_bytes += chunk_len;
+            chunk.extend_from_slice(&self.buffer);
+            self.buffer = chunk;
+            self.buffer_start = start;
+        }
+    }
+}
+
 impl WorkerSessionStore {
     /// Open the Session store rooted at `<worker-aggregate>/session`.
     pub fn new(root: impl Into<PathBuf>) -> Result<Self, StoreError> {
@@ -119,6 +219,19 @@ impl WorkerSessionStore {
         session_id: SessionId,
         segment_id: SegmentId,
     ) -> Result<Vec<LogEntry>, StoreError> {
+        self.read_all_read_only_bounded(session_id, segment_id, u64::MAX)
+            .map(|(entries, _)| entries)
+    }
+
+    /// Read one retained Segment under an actual byte bound without touching
+    /// access time. The file descriptor read, rather than a preceding stat, is
+    /// the limit authority so concurrent appends cannot evade accounting.
+    pub fn read_all_read_only_bounded(
+        &self,
+        session_id: SessionId,
+        segment_id: SegmentId,
+        max_bytes: u64,
+    ) -> Result<(Vec<LogEntry>, u64), StoreError> {
         let retained_session_id = self.session_id.lock().map_err(|_| StoreError::Corrupt {
             line: 0,
             message: "Worker Session identity lock poisoned".to_string(),
@@ -131,14 +244,210 @@ impl WorkerSessionStore {
             });
         }
         let path = self.log_path(segment_id);
-        let bytes = crate::read_without_atime(&path).map_err(|error| {
+        let bytes = crate::read_without_atime_bounded(&path, max_bytes).map_err(|error| {
             if error.kind() == std::io::ErrorKind::NotFound {
                 StoreError::NotFound(segment_id)
             } else {
                 StoreError::Io(error)
             }
         })?;
-        parse_jsonl(&bytes)
+        let byte_len = bytes.len() as u64;
+        if byte_len > max_bytes {
+            return Err(StoreError::ReadLimitExceeded);
+        }
+        Ok((parse_jsonl(&bytes)?, byte_len))
+    }
+
+    pub(crate) fn read_first_log_record_read_only_bounded(
+        &self,
+        session_id: SessionId,
+        segment_id: SegmentId,
+        max_bytes: u64,
+    ) -> Result<(Option<RetainedLogRecord>, u64, u64), StoreError> {
+        self.validate_retained_session(session_id)?;
+        let file = open_retained_file(&self.log_path(segment_id)).map_err(|error| {
+            if error.kind() == std::io::ErrorKind::NotFound {
+                StoreError::NotFound(segment_id)
+            } else {
+                StoreError::Io(error)
+            }
+        })?;
+        let file_len = file.metadata()?.len();
+        if file_len == 0 {
+            return Ok((None, 0, 0));
+        }
+        let mut reader = BufReader::new(file.take(max_bytes.saturating_add(1)));
+        let mut record = Vec::new();
+        let read_bytes = reader.read_until(b'\n', &mut record)? as u64;
+        if read_bytes > max_bytes || record.last() != Some(&b'\n') {
+            return Err(StoreError::ReadLimitExceeded);
+        }
+        record.pop();
+        if record.is_empty() {
+            return Err(StoreError::Corrupt {
+                line: 0,
+                message: "empty retained Segment log record".to_string(),
+            });
+        }
+        let entry = serde_json::from_slice(&record)?;
+        Ok((
+            Some(RetainedLogRecord {
+                start_offset: 0,
+                end_offset: read_bytes,
+                entry,
+            }),
+            read_bytes,
+            file_len,
+        ))
+    }
+
+    pub(crate) fn read_next_log_record_read_only_bounded(
+        &self,
+        session_id: SessionId,
+        segment_id: SegmentId,
+        start_offset: u64,
+        max_bytes: u64,
+    ) -> Result<(Option<RetainedLogRecord>, u64), StoreError> {
+        self.validate_retained_session(session_id)?;
+        let mut file = open_retained_file(&self.log_path(segment_id)).map_err(|error| {
+            if error.kind() == std::io::ErrorKind::NotFound {
+                StoreError::NotFound(segment_id)
+            } else {
+                StoreError::Io(error)
+            }
+        })?;
+        let file_len = file.metadata()?.len();
+        if start_offset >= file_len {
+            return Ok((None, 0));
+        }
+        file.seek(SeekFrom::Start(start_offset))?;
+        let mut reader = BufReader::new(file.take(max_bytes.saturating_add(1)));
+        let mut record = Vec::new();
+        let read_bytes = reader.read_until(b'\n', &mut record)? as u64;
+        if read_bytes > max_bytes || record.last() != Some(&b'\n') {
+            return Err(StoreError::ReadLimitExceeded);
+        }
+        record.pop();
+        if record.is_empty() {
+            return Err(StoreError::Corrupt {
+                line: 0,
+                message: "empty retained Segment log record".to_string(),
+            });
+        }
+        let entry = serde_json::from_slice(&record)?;
+        Ok((
+            Some(RetainedLogRecord {
+                start_offset,
+                end_offset: start_offset + read_bytes,
+                entry,
+            }),
+            read_bytes,
+        ))
+    }
+
+    pub(crate) fn read_log_record_range_read_only_bounded(
+        &self,
+        session_id: SessionId,
+        segment_id: SegmentId,
+        start_offset: u64,
+        end_offset: u64,
+        max_bytes: u64,
+    ) -> Result<RetainedLogRecord, StoreError> {
+        self.validate_retained_session(session_id)?;
+        let record_len =
+            end_offset
+                .checked_sub(start_offset)
+                .ok_or_else(|| StoreError::Corrupt {
+                    line: 0,
+                    message: "retained Segment record range is reversed".to_string(),
+                })?;
+        if record_len == 0 || record_len > max_bytes {
+            return Err(StoreError::ReadLimitExceeded);
+        }
+        let mut file = open_retained_file(&self.log_path(segment_id)).map_err(|error| {
+            if error.kind() == std::io::ErrorKind::NotFound {
+                StoreError::NotFound(segment_id)
+            } else {
+                StoreError::Io(error)
+            }
+        })?;
+        if end_offset > file.metadata()?.len() {
+            return Err(StoreError::Corrupt {
+                line: 0,
+                message: "retained Segment record range exceeds the committed log".to_string(),
+            });
+        }
+        file.seek(SeekFrom::Start(start_offset))?;
+        let mut record = vec![0_u8; record_len as usize];
+        file.read_exact(&mut record)?;
+        if record.last() != Some(&b'\n') || record[..record.len() - 1].contains(&b'\n') {
+            return Err(StoreError::Corrupt {
+                line: 0,
+                message: "retained Segment cursor does not identify one record".to_string(),
+            });
+        }
+        record.pop();
+        let entry = serde_json::from_slice(&record)?;
+        Ok(RetainedLogRecord {
+            start_offset,
+            end_offset,
+            entry,
+        })
+    }
+
+    pub(crate) fn open_retained_segment_reader(
+        &self,
+        session_id: SessionId,
+        segment_id: SegmentId,
+        before_offset: u64,
+    ) -> Result<RetainedSegmentReader, StoreError> {
+        self.validate_retained_session(session_id)?;
+        let mut file = open_retained_file(&self.log_path(segment_id)).map_err(|error| {
+            if error.kind() == std::io::ErrorKind::NotFound {
+                StoreError::NotFound(segment_id)
+            } else {
+                StoreError::Io(error)
+            }
+        })?;
+        let file_len = file.metadata()?.len();
+        if before_offset > file_len {
+            return Err(StoreError::Corrupt {
+                line: 0,
+                message: "retained Segment cursor is beyond the committed log".to_string(),
+            });
+        }
+        if before_offset > 0 {
+            file.seek(SeekFrom::Start(before_offset - 1))?;
+            let mut boundary = [0_u8; 1];
+            file.read_exact(&mut boundary)?;
+            if boundary[0] != b'\n' {
+                return Err(StoreError::Corrupt {
+                    line: 0,
+                    message: "retained Segment cursor is not at a record boundary".to_string(),
+                });
+            }
+        }
+        Ok(RetainedSegmentReader {
+            file,
+            read_end: before_offset,
+            buffer_start: before_offset,
+            buffer: Vec::new(),
+        })
+    }
+
+    fn validate_retained_session(&self, requested: SessionId) -> Result<(), StoreError> {
+        let retained_session_id = self.session_id.lock().map_err(|_| StoreError::Corrupt {
+            line: 0,
+            message: "Worker Session identity lock poisoned".to_string(),
+        })?;
+        if *retained_session_id != Some(requested) {
+            return Err(StoreError::Corrupt {
+                line: 0,
+                message: "active Worker Session identity does not match retained manifest"
+                    .to_string(),
+            });
+        }
+        Ok(())
     }
 
     pub fn segment_log_len(&self, segment_id: SegmentId) -> Result<u64, StoreError> {
@@ -649,6 +958,25 @@ impl Store for WorkerSessionStore {
     }
 }
 
+fn open_retained_file(path: &Path) -> std::io::Result<File> {
+    #[cfg(any(target_os = "linux", target_os = "android"))]
+    {
+        use std::os::unix::fs::OpenOptionsExt;
+        OpenOptions::new()
+            .read(true)
+            .custom_flags(libc::O_NOATIME)
+            .open(path)
+    }
+    #[cfg(not(any(target_os = "linux", target_os = "android")))]
+    {
+        let _ = path;
+        Err(std::io::Error::new(
+            std::io::ErrorKind::Unsupported,
+            "read-only retained observation requires no-atime file reads",
+        ))
+    }
+}
+
 fn segment_log_paths(root: &Path) -> Result<Vec<(SegmentId, PathBuf)>, StoreError> {
     let segments = root.join(SEGMENTS_DIR);
     if !segments.exists() {

crates/standalone/tests/host.rs

@@ -117,7 +117,7 @@ async fn in_process_host_runs_text_and_read_tool_then_shuts_down() {
                 .expect("protocol event")
                 .expect("worker event")
             {
-                Event::UserMessage { segments }
+                Event::UserMessage { segments, .. }
                     if format!("{segments:?}").contains("read the probe") =>
                 {
                     saw_user_message = true;

crates/tools/src/view_image.rs

@@ -7,12 +7,14 @@ use agen::tool::{
 };
 use async_trait::async_trait;
 use serde::Deserialize;
-use workdir::{ReadRequest, WorkdirPath, WorkdirSessionHandle, WorkdirSessionRouter};
+use workdir::{ReadBytesRequest, WorkdirPath, WorkdirSessionHandle, WorkdirSessionRouter};
 
 use crate::error::ToolsError;
 
 /// Maximum image body accepted for one model request.
 pub const MAX_IMAGE_BYTES: usize = 10 * 1024 * 1024;
+/// One binary response remains within the External Workdir transport bound.
+const IMAGE_READ_CHUNK_BYTES: usize = 1024 * 1024;
 
 const DESCRIPTION: &str = "Attach an image from the selected Workdir attachment to the next model request. \
 The path must be logical and Workdir-relative. Supported formats: PNG, JPEG, GIF, and WebP. \
@@ -47,42 +49,111 @@ impl Tool for ViewImageTool {
             workdir::WorkdirSessionCapability::Read,
         )?;
         let path = WorkdirPath::new(&input.path).map_err(ToolsError::from)?;
-        let result = selected
-            .session
-            .read(ReadRequest {
-                path: path.clone(),
-                offset: 0,
-                limit: usize::MAX,
-                // The scoped provider enforces this cap while reading, rather
-                // than allocating an unbounded binary body first.
-                max_bytes: MAX_IMAGE_BYTES + 1,
-            })
+        let bytes = read_image_bytes(selected.session.as_ref(), path.clone())
             .await
             .map_err(ToolsError::from)?;
-
-        if result.truncated || result.bytes.len() > MAX_IMAGE_BYTES {
-            return Err(ToolError::InvalidArgument(format!(
-                "image exceeds the {MAX_IMAGE_BYTES}-byte limit"
-            )));
-        }
-        let mime_type = detect_image_mime(&result.bytes).ok_or_else(|| {
+        let mime_type = detect_image_mime(&bytes).ok_or_else(|| {
             ToolError::InvalidArgument(
                 "unsupported image; expected PNG, JPEG, GIF, or WebP bytes".to_string(),
             )
         })?;
-        let bytes = result.bytes.len();
+        let byte_count = bytes.len();
 
         Ok(ToolOutput {
-            summary: format!("Attached image {path} ({mime_type}, {bytes} bytes)"),
+            summary: format!("Attached image {path} ({mime_type}, {byte_count} bytes)"),
             content: None,
             attachments: vec![Attachment::Image(ImageAttachment::new(
                 mime_type,
-                Arc::<[u8]>::from(result.bytes),
+                Arc::<[u8]>::from(bytes),
             ))],
         })
     }
 }
 
+async fn read_image_bytes(
+    session: &dyn workdir::WorkdirSession,
+    path: WorkdirPath,
+) -> Result<Vec<u8>, workdir::WorkdirError> {
+    let mut bytes = Vec::new();
+    let mut offset = 0_u64;
+    let mut expected_hash = None;
+    let mut expected_total = None;
+
+    loop {
+        let remaining = expected_total
+            .map(|total: u64| total.saturating_sub(offset) as usize)
+            .unwrap_or(IMAGE_READ_CHUNK_BYTES);
+        let request_bytes = remaining.min(IMAGE_READ_CHUNK_BYTES).max(1);
+        let result = session
+            .read_bytes(ReadBytesRequest {
+                path: path.clone(),
+                offset,
+                max_bytes: request_bytes,
+                expected_hash,
+            })
+            .await?;
+
+        if result.path != path || result.offset != offset {
+            return Err(workdir::WorkdirError::Transport(
+                "bounded binary read returned a mismatched path or offset".to_string(),
+            ));
+        }
+        if result.bytes.len() > request_bytes {
+            return Err(workdir::WorkdirError::Transport(
+                "bounded binary read exceeded the requested response size".to_string(),
+            ));
+        }
+        let end = result
+            .offset
+            .checked_add(result.bytes.len() as u64)
+            .ok_or_else(|| {
+                workdir::WorkdirError::Transport(
+                    "bounded binary read returned an invalid byte range".to_string(),
+                )
+            })?;
+        if end > result.total_bytes || result.eof != (end == result.total_bytes) {
+            return Err(workdir::WorkdirError::Transport(
+                "bounded binary read returned a truncated or invalid byte range".to_string(),
+            ));
+        }
+        if result.total_bytes > MAX_IMAGE_BYTES as u64 {
+            return Err(workdir::WorkdirError::InvalidArgument(format!(
+                "image exceeds the {MAX_IMAGE_BYTES}-byte limit"
+            )));
+        }
+        if expected_total.is_some_and(|total| total != result.total_bytes)
+            || expected_hash.is_some_and(|hash| hash != result.content_hash)
+        {
+            return Err(workdir::WorkdirError::Conflict(
+                "image changed while it was being read; retry ViewImage".to_string(),
+            ));
+        }
+        if expected_total.is_none() {
+            bytes
+                .try_reserve_exact(result.total_bytes as usize)
+                .map_err(|_| workdir::WorkdirError::OperationFailed)?;
+            expected_total = Some(result.total_bytes);
+            expected_hash = Some(result.content_hash);
+        }
+
+        if result.bytes.is_empty() && !result.eof {
+            return Err(workdir::WorkdirError::Transport(
+                "bounded binary read made no progress".to_string(),
+            ));
+        }
+        bytes.extend_from_slice(&result.bytes);
+        offset = end;
+        if result.eof {
+            if bytes.len() as u64 != result.total_bytes {
+                return Err(workdir::WorkdirError::Transport(
+                    "bounded binary read returned a partial image".to_string(),
+                ));
+            }
+            return Ok(bytes);
+        }
+    }
+}
+
 pub fn view_image_tool(session: WorkdirSessionHandle) -> ToolDefinition {
     routed_view_image_tool(crate::routing::singleton_router(session))
 }

crates/tools/tests/integration.rs

@@ -18,7 +18,9 @@ use tools::{
     Tracker, core_builtin_tools, routed_builtin_tools, routed_view_image_tool, view_image_tool,
 };
 use workdir::{
-    LocalWorkdirSession, WorkdirAttachmentAlias, WorkdirSessionHandle, WorkdirSessionRouter,
+    LocalWorkdirSession, WorkdirAttachmentAlias, WorkdirPath, WorkdirSessionHandle,
+    WorkdirSessionRouter, WorkdirToolBroker, WorkdirToolScope, WorkdirToolScopePermission,
+    WorkdirToolScopeRule,
 };
 
 fn scope_with_spill(workspace: &Path, spill: &Path) -> Scope {
@@ -94,6 +96,33 @@ fn setup_routed() -> (
     (left, right, spill, router, Registry::new(definitions))
 }
 
+fn valid_gif_with_len(target_len: usize) -> Vec<u8> {
+    let fixture = include_bytes!("fixtures/view-image/valid.gif");
+    assert_eq!(
+        fixture.last(),
+        Some(&0x3b),
+        "GIF fixture must end in trailer"
+    );
+    let mut bytes = fixture[..fixture.len() - 1].to_vec();
+    bytes.extend_from_slice(&[0x21, 0xfe]);
+    let mut remaining = target_len
+        .checked_sub(bytes.len() + 2)
+        .expect("target must leave room for comment terminator and GIF trailer");
+    while remaining > 0 {
+        let mut block = remaining.min(256);
+        if remaining - block == 1 {
+            block -= 1;
+        }
+        assert!(block >= 2);
+        bytes.push((block - 1) as u8);
+        bytes.extend(std::iter::repeat_n(b'x', block - 1));
+        remaining -= block;
+    }
+    bytes.extend_from_slice(&[0, 0x3b]);
+    assert_eq!(bytes.len(), target_len);
+    bytes
+}
+
 async fn call(tool: &Arc<dyn Tool>, input: serde_json::Value) -> agen::tool::ToolOutput {
     tool.execute(&input.to_string(), Default::default())
         .await
@@ -399,6 +428,301 @@ async fn detach_and_reattach_same_alias_requires_a_fresh_read() {
     router.close_all().await.unwrap();
 }
 
+#[derive(Debug)]
+struct ExternalValidatingSession {
+    inner: LocalWorkdirSession,
+    truncate_first_binary_response: bool,
+    mutate_after_first_binary_response: Option<std::path::PathBuf>,
+}
+
+#[async_trait::async_trait]
+impl workdir::WorkdirSession for ExternalValidatingSession {
+    fn workdir(&self) -> &workdir::Workdir {
+        self.inner.workdir()
+    }
+
+    fn capabilities(&self) -> workdir::WorkdirSessionCapabilities {
+        self.inner.capabilities()
+    }
+
+    async fn stat(
+        &self,
+        request: workdir::StatRequest,
+    ) -> Result<workdir::StatResult, workdir::WorkdirError> {
+        self.inner.stat(request).await
+    }
+
+    async fn read(
+        &self,
+        request: workdir::ReadRequest,
+    ) -> Result<workdir::ReadResult, workdir::WorkdirError> {
+        let operation = workdir::http::WorkdirSessionOperation::Read(request);
+        let operation = workdir::external::ExternalWorkdirOperation::try_from(operation)
+            .map_err(workdir::WorkdirError::UnsupportedOperation)?;
+        let workdir::http::WorkdirSessionOperation::Read(request) = operation.into_inner() else {
+            unreachable!("validated Read changed operation kind")
+        };
+        self.inner.read(request).await
+    }
+
+    async fn read_bytes(
+        &self,
+        request: workdir::ReadBytesRequest,
+    ) -> Result<workdir::ReadBytesResult, workdir::WorkdirError> {
+        let operation = workdir::http::WorkdirSessionOperation::ReadBytes(request);
+        let operation = workdir::external::ExternalWorkdirOperation::try_from(operation)
+            .map_err(workdir::WorkdirError::UnsupportedOperation)?;
+        let workdir::http::WorkdirSessionOperation::ReadBytes(request) = operation.into_inner()
+        else {
+            unreachable!("validated ReadBytes changed operation kind")
+        };
+        let result = self.inner.read_bytes(request).await?;
+        let result = workdir::external::ExternalWorkdirOperationResult::try_from(
+            workdir::http::WorkdirSessionOperationResult::ReadBytes(result),
+        )
+        .map_err(workdir::WorkdirError::UnsupportedOperation)?;
+        let workdir::http::WorkdirSessionOperationResult::ReadBytes(mut result) =
+            result.into_inner()
+        else {
+            unreachable!("validated ReadBytes result changed operation kind")
+        };
+        if result.offset == 0 {
+            if let Some(path) = &self.mutate_after_first_binary_response {
+                std::fs::write(path, vec![b'z'; result.total_bytes as usize]).unwrap();
+            }
+            if self.truncate_first_binary_response {
+                result.bytes.pop();
+            }
+        }
+        Ok(result)
+    }
+
+    async fn write(
+        &self,
+        request: workdir::WriteRequest,
+    ) -> Result<workdir::WriteResult, workdir::WorkdirError> {
+        self.inner.write(request).await
+    }
+
+    async fn edit(
+        &self,
+        request: workdir::EditRequest,
+    ) -> Result<workdir::EditResult, workdir::WorkdirError> {
+        self.inner.edit(request).await
+    }
+
+    async fn list(
+        &self,
+        request: workdir::ListRequest,
+    ) -> Result<workdir::ListResult, workdir::WorkdirError> {
+        self.inner.list(request).await
+    }
+
+    async fn glob(
+        &self,
+        request: workdir::GlobRequest,
+    ) -> Result<workdir::GlobResult, workdir::WorkdirError> {
+        self.inner.glob(request).await
+    }
+
+    async fn grep(
+        &self,
+        request: workdir::GrepRequest,
+    ) -> Result<workdir::GrepResult, workdir::WorkdirError> {
+        self.inner.grep(request).await
+    }
+
+    async fn start_command(
+        &self,
+        request: workdir::CommandRequest,
+    ) -> Result<workdir::CommandHandle, workdir::WorkdirError> {
+        self.inner.start_command(request).await
+    }
+
+    async fn command_status(
+        &self,
+        handle: workdir::CommandHandle,
+    ) -> Result<workdir::CommandStatus, workdir::WorkdirError> {
+        self.inner.command_status(handle).await
+    }
+
+    async fn command_output(
+        &self,
+        request: workdir::CommandOutputRequest,
+    ) -> Result<workdir::CommandOutput, workdir::WorkdirError> {
+        self.inner.command_output(request).await
+    }
+
+    async fn cancel_command(
+        &self,
+        handle: workdir::CommandHandle,
+    ) -> Result<(), workdir::WorkdirError> {
+        self.inner.cancel_command(handle).await
+    }
+
+    async fn close(&self) -> Result<(), workdir::WorkdirError> {
+        self.inner.close().await
+    }
+}
+
+#[tokio::test]
+async fn external_view_image_uses_a_protocol_bounded_request() {
+    let dir = TempDir::new().unwrap();
+    let spill = TempDir::new().unwrap();
+    let scope = scope_with_spill(dir.path(), spill.path());
+    let session: WorkdirSessionHandle = Arc::new(ExternalValidatingSession {
+        inner: LocalWorkdirSession::new(scope, dir.path().to_path_buf()),
+        truncate_first_binary_response: false,
+        mutate_after_first_binary_response: None,
+    });
+    let png = include_bytes!("fixtures/view-image/valid.png");
+    assert!(png.contains(&0));
+    assert!(png.iter().any(|byte| *byte >= 0x80));
+    std::fs::write(dir.path().join("image.png"), png).unwrap();
+    let (_meta, tool) = view_image_tool(session)();
+
+    let output = call(&tool, json!({ "path": "image.png" })).await;
+    let agen::tool::Attachment::Image(image) = &output.attachments[0];
+    assert_eq!(image.mime_type(), "image/png");
+    assert_eq!(image.data(), png);
+}
+
+#[tokio::test]
+async fn external_view_image_rejects_truncated_and_cross_version_chunks() {
+    let dir = TempDir::new().unwrap();
+    let spill = TempDir::new().unwrap();
+    let image_path = dir.path().join("image.png");
+    let scope = scope_with_spill(dir.path(), spill.path());
+    std::fs::write(&image_path, include_bytes!("fixtures/view-image/valid.png")).unwrap();
+    let truncated: WorkdirSessionHandle = Arc::new(ExternalValidatingSession {
+        inner: LocalWorkdirSession::new(scope.clone(), dir.path().to_path_buf()),
+        truncate_first_binary_response: true,
+        mutate_after_first_binary_response: None,
+    });
+    let (_meta, tool) = view_image_tool(truncated)();
+    let error = call_err(&tool, json!({ "path": "image.png" }))
+        .await
+        .to_string();
+    assert!(
+        error.contains("truncated") || error.contains("partial"),
+        "{error}"
+    );
+
+    let large = valid_gif_with_len(1024 * 1024 + 32);
+    std::fs::write(&image_path, large).unwrap();
+    let changing: WorkdirSessionHandle = Arc::new(ExternalValidatingSession {
+        inner: LocalWorkdirSession::new(scope, dir.path().to_path_buf()),
+        truncate_first_binary_response: false,
+        mutate_after_first_binary_response: Some(image_path),
+    });
+    let (_meta, tool) = view_image_tool(changing)();
+    let error = call_err(&tool, json!({ "path": "image.png" }))
+        .await
+        .to_string();
+    assert!(error.contains("changed"), "{error}");
+}
+
+#[tokio::test]
+async fn view_image_enforces_the_ten_mib_boundary_without_partial_attachments() {
+    const LIMIT: usize = 10 * 1024 * 1024;
+    let dir = TempDir::new().unwrap();
+    let spill = TempDir::new().unwrap();
+    let scope = scope_with_spill(dir.path(), spill.path());
+    let session: WorkdirSessionHandle =
+        Arc::new(LocalWorkdirSession::new(scope, dir.path().to_path_buf()));
+    let (_meta, tool) = view_image_tool(session)();
+    let mut image = valid_gif_with_len(LIMIT);
+    std::fs::write(dir.path().join("boundary.gif"), &image).unwrap();
+
+    let output = call(&tool, json!({ "path": "boundary.gif" })).await;
+    let agen::tool::Attachment::Image(attachment) = &output.attachments[0];
+    assert_eq!(attachment.mime_type(), "image/gif");
+    assert_eq!(attachment.data(), image);
+
+    image.push(0);
+    std::fs::write(dir.path().join("boundary.gif"), image).unwrap();
+    let error = call_err(&tool, json!({ "path": "boundary.gif" }))
+        .await
+        .to_string();
+    assert!(error.contains("10485760-byte limit"), "{error}");
+}
+
+#[tokio::test]
+async fn view_image_attaches_valid_supported_image_fixtures() {
+    let dir = TempDir::new().unwrap();
+    let spill = TempDir::new().unwrap();
+    let scope = scope_with_spill(dir.path(), spill.path());
+    let session: WorkdirSessionHandle =
+        Arc::new(LocalWorkdirSession::new(scope, dir.path().to_path_buf()));
+    let (_meta, tool) = view_image_tool(session)();
+    let fixtures: [(&str, &[u8], &str); 4] = [
+        (
+            "valid.png",
+            include_bytes!("fixtures/view-image/valid.png"),
+            "image/png",
+        ),
+        (
+            "valid.jpg",
+            include_bytes!("fixtures/view-image/valid.jpg"),
+            "image/jpeg",
+        ),
+        (
+            "valid.gif",
+            include_bytes!("fixtures/view-image/valid.gif"),
+            "image/gif",
+        ),
+        (
+            "valid.webp",
+            include_bytes!("fixtures/view-image/valid.webp"),
+            "image/webp",
+        ),
+    ];
+
+    for (name, fixture, mime) in fixtures {
+        std::fs::write(dir.path().join(name), fixture).unwrap();
+        let output = call(&tool, json!({ "path": name })).await;
+        let agen::tool::Attachment::Image(image) = &output.attachments[0];
+        assert_eq!(image.mime_type(), mime);
+        assert_eq!(image.data(), fixture);
+    }
+}
+
+#[tokio::test]
+async fn delegated_view_image_preserves_caller_relative_path_identity() {
+    let dir = TempDir::new().unwrap();
+    std::fs::create_dir(dir.path().join("docs")).unwrap();
+    let fixture = include_bytes!("fixtures/view-image/valid.png");
+    std::fs::write(dir.path().join("docs/image.png"), fixture).unwrap();
+    let source: WorkdirSessionHandle = Arc::new(LocalWorkdirSession::new(
+        Scope::writable(dir.path()).unwrap(),
+        dir.path().to_path_buf(),
+    ));
+    let broker = WorkdirToolBroker::new(source);
+    let lease = broker
+        .scope(WorkdirToolScope {
+            rules: vec![WorkdirToolScopeRule {
+                target: WorkdirPath::new("docs").unwrap(),
+                permission: WorkdirToolScopePermission::Read,
+                recursive: true,
+                symlink_policy: Default::default(),
+            }],
+            cwd: WorkdirPath::new("docs").unwrap(),
+            command: false,
+        })
+        .await
+        .unwrap();
+    let (_meta, tool) = view_image_tool(lease.tool_session())();
+
+    let output = call(&tool, json!({ "path": "image.png" })).await;
+    assert!(output.summary.contains("image.png"));
+    assert!(!output.summary.contains("docs/image.png"));
+    let agen::tool::Attachment::Image(image) = &output.attachments[0];
+    assert_eq!(image.data(), fixture);
+
+    lease.close().await.unwrap();
+    broker.close().await.unwrap();
+}
+
 #[tokio::test]
 async fn view_image_reads_scoped_bytes_into_durable_tool_detail() {
     let dir = TempDir::new().unwrap();
@@ -406,7 +730,7 @@ async fn view_image_reads_scoped_bytes_into_durable_tool_detail() {
     let scope = scope_with_spill(dir.path(), spill.path());
     let session: WorkdirSessionHandle =
         Arc::new(LocalWorkdirSession::new(scope, dir.path().to_path_buf()));
-    let png = b"\x89PNG\r\n\x1a\nprivate-image-body";
+    let png = include_bytes!("fixtures/view-image/valid.png");
     std::fs::write(dir.path().join("image.png"), png).unwrap();
     let definition = view_image_tool(session);
     let (_meta, tool) = definition();
@@ -417,7 +741,6 @@ async fn view_image_reads_scoped_bytes_into_durable_tool_detail() {
     assert_eq!(image.mime_type(), "image/png");
     assert_eq!(image.data(), png);
     let serialized = serde_json::to_string(&output).unwrap();
-    assert!(!serialized.contains("private-image-body"));
     assert!(serialized.contains("attachments"));
     let restored: agen::tool::ToolOutput = serde_json::from_str(&serialized).unwrap();
     let agen::tool::Attachment::Image(restored_image) = &restored.attachments[0];

crates/tui/src/app.rs

@@ -1148,7 +1148,7 @@ impl App {
             Event::PendingSubmissionsChanged { pending } => {
                 self.pending_submissions = pending;
             }
-            Event::UserMessage { segments } => {
+            Event::UserMessage { segments, .. } => {
                 self.turn_index += 1;
                 self.blocks.push(Block::TurnHeader {
                     turn: self.turn_index,
@@ -1168,6 +1168,9 @@ impl App {
                 }
                 self.assistant_streaming = false;
             }
+            // The TUI already renders assistant/tool streaming events. This commit
+            // marker exists so identity-aware clients can reconcile durable history.
+            Event::SessionEntryCommitted { .. } => {}
             Event::SystemItem { item } => {
                 self.apply_system_item(&item);
                 self.assistant_streaming = false;
@@ -3391,6 +3394,7 @@ mod completion_flow_tests {
             ]),
         });
         app.handle_worker_event(Event::UserMessage {
+            entry_id: None,
             segments: vec![Segment::text("first persisted message")],
         });
 
@@ -3409,6 +3413,7 @@ mod completion_flow_tests {
         assert_eq!(input_text(&app), "");
 
         app.handle_worker_event(Event::UserMessage {
+            entry_id: None,
             segments: submitted,
         });
         // Simulate run-derived attachment display after the submitted user line.
@@ -3449,6 +3454,7 @@ mod completion_flow_tests {
         let mut app = App::new("test".into());
         let submitted = submit_text(&mut app, "original submit");
         app.handle_worker_event(Event::UserMessage {
+            entry_id: None,
             segments: submitted,
         });
         for c in "draft while running".chars() {
@@ -3477,6 +3483,7 @@ mod completion_flow_tests {
             let mut app = App::new("test".into());
             let submitted = submit_text(&mut app, "normal run");
             app.handle_worker_event(Event::UserMessage {
+                entry_id: None,
                 segments: submitted,
             });
             app.handle_worker_event(Event::RunEnd { result });

crates/tui/src/console/mod.rs

@@ -1688,6 +1688,7 @@ mod tests {
         );
 
         connection.observe_worker_event(&Event::UserMessage {
+            entry_id: None,
             segments: vec![Segment::text("inspect"), Segment::UploadedFile { file }],
         });
         assert!(connection.pending_attachments.is_empty());
@@ -1779,7 +1780,10 @@ mod tests {
             assert!(!reconcile_attachment_submission(
                 &mut pending,
                 &mut awaiting,
-                &Event::UserMessage { segments },
+                &Event::UserMessage {
+                    entry_id: None,
+                    segments,
+                },
             ));
             assert_eq!(awaiting, expected);
             assert!(pending.is_empty());

crates/workdir/src/external.rs

@@ -12,7 +12,7 @@ use serde::{Deserialize, Serialize};
 use crate::http::{WorkdirSessionOperation, WorkdirSessionOperationResult, WorkdirTransportError};
 use crate::{BoundedReadLimits, WorkdirId, WorkdirPath, WorkdirSessionCapabilities};
 
-pub const EXTERNAL_WORKDIR_PROVIDER_PROTOCOL_VERSION: u16 = 1;
+pub const EXTERNAL_WORKDIR_PROVIDER_PROTOCOL_VERSION: u16 = 2;
 /// Maximum serialized Backend-to-provider command frame size.
 pub const MAX_EXTERNAL_SERVER_FRAME_BYTES: usize = 1024 * 1024;
 /// Maximum serialized provider-to-Backend result frame size. Read bytes are
@@ -155,6 +155,12 @@ fn validate_external_operation(operation: &WorkdirSessionOperation) -> Result<()
                 && request.limit <= 1_000_000
                 && request.max_bytes <= BoundedReadLimits::EXTERNAL_DEFAULT.max_response_bytes
         }
+        WorkdirSessionOperation::ReadBytes(request) => {
+            is_root_relative(&request.path)
+                && request.offset <= BoundedReadLimits::EXTERNAL_DEFAULT.max_source_bytes
+                && (1..=BoundedReadLimits::EXTERNAL_DEFAULT.max_response_bytes)
+                    .contains(&request.max_bytes)
+        }
         WorkdirSessionOperation::List(request) => {
             is_root_relative(&request.path) && request.limit <= MAX_EXTERNAL_RESULT_ITEMS
         }
@@ -275,6 +281,15 @@ fn validate_external_result(result: &WorkdirSessionOperationResult) -> Result<()
             is_root_relative(&result.path)
                 && result.bytes.len() <= BoundedReadLimits::EXTERNAL_DEFAULT.max_response_bytes
         }
+        WorkdirSessionOperationResult::ReadBytes(result) => {
+            let returned_end = result.offset.checked_add(result.bytes.len() as u64);
+            is_root_relative(&result.path)
+                && result.bytes.len() <= BoundedReadLimits::EXTERNAL_DEFAULT.max_response_bytes
+                && result.total_bytes <= BoundedReadLimits::EXTERNAL_DEFAULT.max_source_bytes
+                && returned_end.is_some_and(|end| {
+                    end <= result.total_bytes && result.eof == (end == result.total_bytes)
+                })
+        }
         WorkdirSessionOperationResult::List(result) => {
             result.entries.len() <= MAX_EXTERNAL_RESULT_ITEMS
                 && result
@@ -482,8 +497,8 @@ mod tests {
 
     use super::*;
     use crate::{
-        CommandRequest, EditRequest, GrepResult, ListRequest, ReadRequest, Workdir, WorkdirPath,
-        WriteRequest,
+        CommandRequest, EditRequest, GrepResult, ListRequest, ReadBytesRequest, ReadBytesResult,
+        ReadRequest, Workdir, WorkdirPath, WriteRequest,
     };
 
     fn assert_no_provider_authority(value: &Value) {
@@ -614,7 +629,7 @@ mod tests {
     #[test]
     fn unsupported_protocol_versions_and_invalid_read_limits_fail_closed() {
         let future = r#"{
-            "version": 2,
+            "version": 3,
             "message": {"kind": "heartbeat", "generation": 1, "sequence": 1}
         }"#;
         assert!(serde_json::from_str::<ExternalWorkdirServerFrame>(future).is_err());
@@ -726,10 +741,51 @@ mod tests {
         );
     }
 
+    #[test]
+    fn protocol_bounds_binary_read_requests_and_rejects_partial_results() {
+        let path = WorkdirPath::new("image.png").unwrap();
+        let bounded = WorkdirSessionOperation::ReadBytes(ReadBytesRequest {
+            path: path.clone(),
+            offset: 0,
+            max_bytes: BoundedReadLimits::EXTERNAL_DEFAULT.max_response_bytes,
+            expected_hash: None,
+        });
+        assert!(ExternalWorkdirOperation::try_from(bounded).is_ok());
+
+        let oversized = WorkdirSessionOperation::ReadBytes(ReadBytesRequest {
+            path: path.clone(),
+            offset: 0,
+            max_bytes: BoundedReadLimits::EXTERNAL_DEFAULT.max_response_bytes + 1,
+            expected_hash: None,
+        });
+        assert!(ExternalWorkdirOperation::try_from(oversized).is_err());
+
+        let hash = [7; 32];
+        let complete = WorkdirSessionOperationResult::ReadBytes(ReadBytesResult {
+            path: path.clone(),
+            bytes: vec![1, 2, 3],
+            offset: 0,
+            total_bytes: 3,
+            content_hash: hash,
+            eof: true,
+        });
+        assert!(ExternalWorkdirOperationResult::try_from(complete).is_ok());
+
+        let partial_marked_complete = WorkdirSessionOperationResult::ReadBytes(ReadBytesResult {
+            path,
+            bytes: vec![1, 2],
+            offset: 0,
+            total_bytes: 3,
+            content_hash: hash,
+            eof: true,
+        });
+        assert!(ExternalWorkdirOperationResult::try_from(partial_marked_complete).is_err());
+    }
+
     #[test]
     fn protocol_rejects_unknown_nested_fields_and_unbounded_requests() {
         let unknown = r#"{
-            "version": 1,
+            "version": 2,
             "message": {
                 "kind": "heartbeat",
                 "generation": 1,

crates/workdir/src/http.rs

@@ -11,9 +11,9 @@ use serde::{Deserialize, Serialize};
 use crate::{
     CommandHandle, CommandOutput, CommandOutputRequest, CommandRequest, CommandStatus, EditRequest,
     EditResult, GlobRequest, GlobResult, GrepRequest, GrepResult, ListRequest, ListResult,
-    ReadRequest, ReadResult, StatRequest, StatResult, WorkdirError, WorkdirId,
-    WorkdirScopeAuthorizationRequest, WorkdirScopeOverlapRequest, WorkdirSession,
-    WorkdirSessionCapabilities, WriteRequest, WriteResult,
+    ReadBytesRequest, ReadBytesResult, ReadRequest, ReadResult, StatRequest, StatResult,
+    WorkdirError, WorkdirId, WorkdirScopeAuthorizationRequest, WorkdirScopeOverlapRequest,
+    WorkdirSession, WorkdirSessionCapabilities, WriteRequest, WriteResult,
 };
 
 /// Opaque Runtime-owned identifier for one ephemeral Workdir session.
@@ -66,6 +66,7 @@ pub enum WorkdirSessionOperation {
     ScopeRulesOverlap(WorkdirScopeOverlapRequest),
     Stat(StatRequest),
     Read(ReadRequest),
+    ReadBytes(ReadBytesRequest),
     Write(WriteRequest),
     Edit(EditRequest),
     List(ListRequest),
@@ -97,6 +98,7 @@ pub enum WorkdirSessionOperationResult {
     ScopeRulesOverlap { overlaps: bool },
     Stat(StatResult),
     Read(ReadResult),
+    ReadBytes(ReadBytesResult),
     Write(WriteResult),
     Edit(EditResult),
     List(ListResult),
@@ -135,6 +137,10 @@ pub async fn dispatch_workdir_session_operation(
             .read(request)
             .await
             .map(WorkdirSessionOperationResult::Read),
+        WorkdirSessionOperation::ReadBytes(request) => session
+            .read_bytes(request)
+            .await
+            .map(WorkdirSessionOperationResult::ReadBytes),
         WorkdirSessionOperation::Write(request) => session
             .write(request)
             .await
@@ -572,6 +578,19 @@ mod client {
             }
         }
 
+        async fn read_bytes(
+            &self,
+            request: ReadBytesRequest,
+        ) -> Result<ReadBytesResult, WorkdirError> {
+            match self
+                .operate(WorkdirSessionOperation::ReadBytes(request))
+                .await?
+            {
+                WorkdirSessionOperationResult::ReadBytes(result) => Ok(result),
+                _ => Err(Self::mismatch("read_bytes")),
+            }
+        }
+
         async fn write(&self, request: WriteRequest) -> Result<WriteResult, WorkdirError> {
             match self
                 .operate(WorkdirSessionOperation::Write(request))

crates/workdir/src/lib.rs

@@ -27,7 +27,8 @@ use tokio::sync::broadcast;
 pub use fs_operation::{
     BoundedReadLimits, ContentHash, EditRequest, EditResult, EntryKind, FsPath as WorkdirPath,
     GlobRequest, GlobResult, GrepOutputMode, GrepRequest, GrepResult, ListEntry, ListRequest,
-    ListResult, ReadRequest, ReadResult, StatRequest, StatResult, WriteRequest, WriteResult,
+    ListResult, ReadBytesRequest, ReadBytesResult, ReadRequest, ReadResult, StatRequest,
+    StatResult, WriteRequest, WriteResult,
 };
 pub use http::dispatch_workdir_session_operation;
 pub use local::{
@@ -220,6 +221,14 @@ pub trait WorkdirSession: std::fmt::Debug + Send + Sync {
 
     async fn stat(&self, request: StatRequest) -> Result<StatResult, WorkdirError>;
     async fn read(&self, request: ReadRequest) -> Result<ReadResult, WorkdirError>;
+    async fn read_bytes(
+        &self,
+        _request: ReadBytesRequest,
+    ) -> Result<ReadBytesResult, WorkdirError> {
+        Err(WorkdirError::UnsupportedOperation(
+            "bounded binary reads are not supported by this provider".to_string(),
+        ))
+    }
     async fn write(&self, request: WriteRequest) -> Result<WriteResult, WorkdirError>;
     async fn edit(&self, request: EditRequest) -> Result<EditResult, WorkdirError>;
     async fn list(&self, request: ListRequest) -> Result<ListResult, WorkdirError>;

crates/workdir/src/local.rs

@@ -30,10 +30,10 @@ use crate::{
     BoundedReadLimits, CommandEvent, CommandHandle, CommandOutput, CommandOutputRequest,
     CommandRequest, CommandSnapshot, CommandStatus, CommandStream, CommandStreamSlice, EditRequest,
     EditResult, GlobRequest, GlobResult, GrepRequest, GrepResult, ListRequest, ListResult,
-    ReadRequest, ReadResult, StatRequest, StatResult, Workdir, WorkdirError, WorkdirPath,
-    WorkdirScopeAuthorizationRequest, WorkdirScopeOverlapRequest, WorkdirSession,
-    WorkdirSessionCapabilities, WorkdirSessionCapability, WorkdirToolScopePermission, WriteRequest,
-    WriteResult,
+    ReadBytesRequest, ReadBytesResult, ReadRequest, ReadResult, StatRequest, StatResult, Workdir,
+    WorkdirError, WorkdirPath, WorkdirScopeAuthorizationRequest, WorkdirScopeOverlapRequest,
+    WorkdirSession, WorkdirSessionCapabilities, WorkdirSessionCapability,
+    WorkdirToolScopePermission, WriteRequest, WriteResult,
 };
 #[cfg(test)]
 use crate::{EntryKind, WriteOutcome};
@@ -1261,6 +1261,21 @@ impl WorkdirSession for LocalWorkdirSession {
         .map_err(|error| sanitize_error(error, &logical))
     }
 
+    async fn read_bytes(&self, request: ReadBytesRequest) -> Result<ReadBytesResult, WorkdirError> {
+        self.ensure_capability(WorkdirSessionCapability::Read)?;
+        let logical = request.path.clone();
+        self.validate_operation_path(&request.path)?;
+        let access = self.scope_access();
+        match self.inner.read_limits {
+            Some(limits) => {
+                fs_operation::run_read_bytes_bounded(&self.inner.root, request, &access, limits)
+            }
+            None => fs_operation::run_read_bytes(&self.inner.root, request, &access),
+        }
+        .map_err(WorkdirError::from)
+        .map_err(|error| sanitize_error(error, &logical))
+    }
+
     async fn write(&self, request: WriteRequest) -> Result<WriteResult, WorkdirError> {
         self.ensure_capability(WorkdirSessionCapability::Write)?;
         let logical = request.path.clone();

crates/workdir/src/router.rs

@@ -16,9 +16,10 @@ use tokio::sync::broadcast;
 use crate::{
     CommandEvent, CommandHandle, CommandOutput, CommandOutputRequest, CommandRequest,
     CommandSnapshot, CommandStatus, EditRequest, EditResult, GlobRequest, GlobResult, GrepRequest,
-    GrepResult, ListRequest, ListResult, ReadRequest, ReadResult, StatRequest, StatResult, Workdir,
-    WorkdirError, WorkdirScopeAuthorizationRequest, WorkdirScopeOverlapRequest, WorkdirSession,
-    WorkdirSessionCapabilities, WorkdirSessionHandle, WriteRequest, WriteResult,
+    GrepResult, ListRequest, ListResult, ReadBytesRequest, ReadBytesResult, ReadRequest,
+    ReadResult, StatRequest, StatResult, Workdir, WorkdirError, WorkdirScopeAuthorizationRequest,
+    WorkdirScopeOverlapRequest, WorkdirSession, WorkdirSessionCapabilities, WorkdirSessionHandle,
+    WriteRequest, WriteResult,
 };
 
 /// Stable Worker-local routing key for one attached Workdir.
@@ -257,6 +258,11 @@ impl WorkdirSession for RoutedWorkdirSession {
         self.state.session.read(request).await
     }
 
+    async fn read_bytes(&self, request: ReadBytesRequest) -> Result<ReadBytesResult, WorkdirError> {
+        let _active = self.state.enter()?;
+        self.state.session.read_bytes(request).await
+    }
+
     async fn write(&self, request: WriteRequest) -> Result<WriteResult, WorkdirError> {
         let _active = self.state.enter()?;
         self.state.session.write(request).await

crates/workdir/src/scope.rs

@@ -6,7 +6,8 @@ use std::sync::{Arc, Mutex, Weak};
 use async_trait::async_trait;
 use fs_operation::{
     EditRequest, EditResult, FsPath, GlobRequest, GlobResult, GrepRequest, GrepResult, ListRequest,
-    ListResult, ReadRequest, ReadResult, StatRequest, StatResult, WriteRequest, WriteResult,
+    ListResult, ReadBytesRequest, ReadBytesResult, ReadRequest, ReadResult, StatRequest,
+    StatResult, WriteRequest, WriteResult,
 };
 use manifest::SymlinkPolicy;
 use schemars::JsonSchema;
@@ -1011,6 +1012,21 @@ impl WorkdirSession for ScopedWorkdirSession {
         self.source.read(request).await
     }
 
+    async fn read_bytes(
+        &self,
+        mut request: ReadBytesRequest,
+    ) -> Result<ReadBytesResult, WorkdirError> {
+        let caller_path = request.path.clone();
+        let path = self
+            .resolve_operation_path(&request.path, WorkdirToolScopePermission::Read)
+            .await?;
+        self.ensure_read(&path, WorkdirSessionCapability::Read)?;
+        request.path = path;
+        let mut result = self.source.read_bytes(request).await?;
+        result.path = caller_path;
+        Ok(result)
+    }
+
     async fn write(&self, mut request: WriteRequest) -> Result<WriteResult, WorkdirError> {
         let _scope_guard = self.scope_lock.lock().await;
         let path = self
@@ -1276,6 +1292,10 @@ impl WorkdirSession for ReadOnlyWorkdirSession {
         self.inner.read(request).await
     }
 
+    async fn read_bytes(&self, request: ReadBytesRequest) -> Result<ReadBytesResult, WorkdirError> {
+        self.inner.read_bytes(request).await
+    }
+
     async fn write(&self, _request: WriteRequest) -> Result<WriteResult, WorkdirError> {
         Err(WorkdirError::Denied("read-only workdir session".into()))
     }
@@ -1656,6 +1676,15 @@ mod tests {
         }
     }
 
+    fn read_bytes(path: &str) -> ReadBytesRequest {
+        ReadBytesRequest {
+            path: fs_path(path),
+            offset: 0,
+            max_bytes: 1024,
+            expected_hash: None,
+        }
+    }
+
     fn write(path: &str, content: &str) -> WriteRequest {
         WriteRequest {
             path: fs_path(path),
@@ -1887,6 +1916,9 @@ mod tests {
             child.read(read("readme.md")).await.unwrap().bytes,
             b"visible"
         );
+        let binary = child.read_bytes(read_bytes("readme.md")).await.unwrap();
+        assert_eq!(binary.path, fs_path("readme.md"));
+        assert_eq!(binary.bytes, b"visible");
         assert!(matches!(
             child.write(write("new.md", "no")).await,
             Err(WorkdirError::Denied(_))

crates/worker-runtime/src/execution.rs

@@ -477,6 +477,13 @@ pub struct WorkerSessionObservationRequest {
     pub worker_ref: WorkerRef,
 }
 
+#[derive(Clone, Debug, PartialEq, Eq)]
+pub struct WorkerSessionHistoryRequest {
+    pub worker_ref: WorkerRef,
+    pub cursor: Option<String>,
+    pub limit: Option<usize>,
+}
+
 pub trait WorkerExecutionBackend: Send + Sync + 'static {
     fn backend_id(&self) -> &str;
 
@@ -497,6 +504,16 @@ pub trait WorkerExecutionBackend: Send + Sync + 'static {
         }
     }
 
+    fn worker_session_history(
+        &self,
+        _request: WorkerSessionHistoryRequest,
+    ) -> runtime_api::WorkerSessionHistoryAvailability {
+        runtime_api::WorkerSessionHistoryAvailability::Unavailable {
+            reason: runtime_api::WorkerSessionHistoryUnavailableReason::Unsupported,
+            message: "session history paging is not supported by this Runtime".to_string(),
+        }
+    }
+
     fn spawn_worker(&self, request: WorkerExecutionSpawnRequest) -> WorkerExecutionSpawnResult;
 
     /// Read-only restore validation performed before any live controller,
@@ -726,6 +743,13 @@ impl WorkerExecutionBackendRef {
         self.backend.worker_session(request)
     }
 
+    pub(crate) fn worker_session_history(
+        &self,
+        request: WorkerSessionHistoryRequest,
+    ) -> runtime_api::WorkerSessionHistoryAvailability {
+        self.backend.worker_session_history(request)
+    }
+
     pub(crate) fn spawn_worker(
         &self,
         request: WorkerExecutionSpawnRequest,

crates/worker-runtime/src/http_server/runtime_management_api.rs

@@ -260,6 +260,35 @@ impl runtime_api::RuntimeApi for RuntimeManagementApi {
             .map_err(api_error)
     }
 
+    async fn worker_session_history(
+        &self,
+        worker_id: String,
+        request: runtime_api::WorkerSessionHistoryRequest,
+    ) -> Result<runtime_api::WorkerSessionHistoryAvailability, runtime_api::RuntimeApiError> {
+        let worker_ref = worker_ref_for(&self.state.runtime, worker_id).map_err(api_error)?;
+        let scope = auth_workspace_scope(&self.state, auth_extension().as_ref())
+            .map_err(api_error)?
+            .ok_or_else(|| {
+                runtime_api::RuntimeApiError::new(
+                    StatusCode::FORBIDDEN.as_u16(),
+                    "runtime_worker_session_scope_required",
+                    "Worker Session history requires a Workspace-scoped capability",
+                )
+            })?;
+        if scope.workspace_id != request.workspace_id {
+            return Err(runtime_api::RuntimeApiError::new(
+                StatusCode::FORBIDDEN.as_u16(),
+                "runtime_worker_session_workspace_scope_mismatch",
+                "Worker Session Workspace scope does not match the authenticated capability",
+            ));
+        }
+        self.state
+            .runtime
+            .worker_session_history_scoped(&scope, &worker_ref, request.cursor, request.limit)
+            .map_err(RuntimeHttpRestError::runtime)
+            .map_err(api_error)
+    }
+
     async fn create_worker(
         &self,
         value: runtime_api::CreateWorkerRequest,

crates/worker-runtime/src/runtime.rs

@@ -16,7 +16,8 @@ use crate::execution::{
     WorkerExecutionBackend, WorkerExecutionBackendRef, WorkerExecutionHandle,
     WorkerExecutionOperation, WorkerExecutionResult, WorkerExecutionSpawnRequest,
     WorkerExecutionSpawnResult, WorkerExecutionStopRequest, WorkerLifecycleOperationId,
-    WorkerSessionObservationRequest, WorkspaceConfigFetchRequest, WorkspaceConfigFetchResult,
+    WorkerSessionHistoryRequest, WorkerSessionObservationRequest, WorkspaceConfigFetchRequest,
+    WorkspaceConfigFetchResult,
 };
 #[cfg(feature = "fs-store")]
 use crate::fs_store::{
@@ -1613,6 +1614,38 @@ impl Runtime {
         })
     }
 
+    /// Read one bounded page from the adopted durable Session lineage without
+    /// restoring the Worker or modifying model context.
+    pub fn worker_session_history_scoped(
+        &self,
+        scope: &RuntimeWorkspaceScope,
+        worker_ref: &WorkerRef,
+        cursor: Option<String>,
+        limit: Option<usize>,
+    ) -> Result<runtime_api::WorkerSessionHistoryAvailability, RuntimeError> {
+        let operation_lock = self.worker_operation_lock(worker_ref.worker_id)?;
+        let _operation_guard = operation_lock
+            .lock()
+            .map_err(|_| RuntimeError::StatePoisoned)?;
+        self.ensure_worker_in_workspace(scope, worker_ref)?;
+        let backend = {
+            let state = self.lock()?;
+            state.worker(worker_ref)?;
+            state.execution_backend.clone()
+        };
+        Ok(match backend {
+            Some(backend) => backend.worker_session_history(WorkerSessionHistoryRequest {
+                worker_ref: worker_ref.clone(),
+                cursor,
+                limit,
+            }),
+            None => runtime_api::WorkerSessionHistoryAvailability::Unavailable {
+                reason: runtime_api::WorkerSessionHistoryUnavailableReason::Unsupported,
+                message: "session history paging is not supported by this Runtime".to_string(),
+            },
+        })
+    }
+
     /// Attach a live execution through a workspace-scoped Runtime authorization context.
     pub fn restore_worker_scoped(
         &self,

crates/worker-runtime/src/worker_backend.rs

@@ -172,6 +172,15 @@ pub trait RuntimeWorkerFactory: Send + Sync + 'static {
         Err(session_store::RetainedSnapshotReadError::RetentionMissing)
     }
 
+    fn retained_session_history_page(
+        &self,
+        _worker_ref: &WorkerRef,
+        _cursor: Option<&str>,
+        _limit: Option<usize>,
+    ) -> Result<protocol::SessionHistoryPage, session_store::RetainedHistoryReadError> {
+        Err(session_store::RetainedHistoryReadError::RetentionMissing)
+    }
+
     async fn spawn_controller(
         &self,
         request: WorkerExecutionSpawnRequest,
@@ -1027,6 +1036,25 @@ impl RuntimeWorkerFactory for ProfileRuntimeWorkerFactory {
         )
     }
 
+    fn retained_session_history_page(
+        &self,
+        worker_ref: &WorkerRef,
+        cursor: Option<&str>,
+        limit: Option<usize>,
+    ) -> Result<protocol::SessionHistoryPage, session_store::RetainedHistoryReadError> {
+        let aggregate_dir = self
+            .worker_aggregate_dir(worker_ref)
+            .map_err(|_| session_store::RetainedHistoryReadError::RetentionMissing)?;
+        let worker_name = Self::runtime_worker_name_for_ref(worker_ref);
+        session_store::read_retained_session_history_page(
+            &aggregate_dir,
+            &worker_name,
+            cursor,
+            limit,
+            session_store::RetainedHistoryReadLimits::default(),
+        )
+    }
+
     fn observe_workspace_prompt_projection(
         &self,
         projection: worker::WorkspacePromptProjection,
@@ -2216,6 +2244,48 @@ where
         }
     }
 
+    fn worker_session_history(
+        &self,
+        request: crate::execution::WorkerSessionHistoryRequest,
+    ) -> runtime_api::WorkerSessionHistoryAvailability {
+        match self.factory.retained_session_history_page(
+            &request.worker_ref,
+            request.cursor.as_deref(),
+            request.limit,
+        ) {
+            Ok(page) => runtime_api::WorkerSessionHistoryAvailability::Page { page },
+            Err(error) => {
+                let reason = match error {
+                    session_store::RetainedHistoryReadError::RetentionMissing => {
+                        runtime_api::WorkerSessionHistoryUnavailableReason::RetentionMissing
+                    }
+                    session_store::RetainedHistoryReadError::ActivePointerMissing => {
+                        runtime_api::WorkerSessionHistoryUnavailableReason::ActivePointerMissing
+                    }
+                    session_store::RetainedHistoryReadError::MigrationRequired => {
+                        runtime_api::WorkerSessionHistoryUnavailableReason::MigrationRequired
+                    }
+                    session_store::RetainedHistoryReadError::CorruptLog => {
+                        runtime_api::WorkerSessionHistoryUnavailableReason::CorruptLog
+                    }
+                    session_store::RetainedHistoryReadError::StorageUnavailable => {
+                        runtime_api::WorkerSessionHistoryUnavailableReason::StorageUnavailable
+                    }
+                    session_store::RetainedHistoryReadError::InvalidCursor => {
+                        runtime_api::WorkerSessionHistoryUnavailableReason::InvalidCursor
+                    }
+                    session_store::RetainedHistoryReadError::ResourceLimit => {
+                        runtime_api::WorkerSessionHistoryUnavailableReason::ResourceLimit
+                    }
+                };
+                runtime_api::WorkerSessionHistoryAvailability::Unavailable {
+                    reason,
+                    message: error.to_string(),
+                }
+            }
+        }
+    }
+
     fn observe_workspace_prompt_projection(
         &self,
         projection: worker::WorkspacePromptProjection,

crates/worker/src/feature/builtin/manage_workdir.rs

@@ -18,8 +18,8 @@ use workdir::workspace::WorkspaceWorkdirSessionOperationRequest;
 use workdir::{
     CommandHandle, CommandOutput, CommandOutputRequest, CommandRequest, CommandStatus, EditRequest,
     EditResult, GlobRequest, GlobResult, GrepRequest, GrepResult, ListRequest, ListResult,
-    ReadRequest, ReadResult, StatRequest, StatResult, Workdir, WorkdirError,
-    WorkdirScopeAuthorizationRequest, WorkdirScopeOverlapRequest, WorkdirSession,
+    ReadBytesRequest, ReadBytesResult, ReadRequest, ReadResult, StatRequest, StatResult, Workdir,
+    WorkdirError, WorkdirScopeAuthorizationRequest, WorkdirScopeOverlapRequest, WorkdirSession,
     WorkdirSessionCapabilities, WorkdirSessionHandle, WriteRequest, WriteResult,
 };
 
@@ -357,6 +357,13 @@ impl WorkdirSession for WorkspaceAttachedWorkdirSession {
         }
     }
 
+    async fn read_bytes(&self, request: ReadBytesRequest) -> Result<ReadBytesResult, WorkdirError> {
+        match self.operate(WorkdirSessionOperation::ReadBytes(request))? {
+            WorkdirSessionOperationResult::ReadBytes(result) => Ok(result),
+            _ => Err(Self::mismatch("read_bytes")),
+        }
+    }
+
     async fn write(&self, request: WriteRequest) -> Result<WriteResult, WorkdirError> {
         match self.operate(WorkdirSessionOperation::Write(request))? {
             WorkdirSessionOperationResult::Write(result) => Ok(result),

crates/worker/src/in_flight.rs

@@ -619,8 +619,8 @@ mod tests {
         let (committed_tx, committed_rx) = mpsc::channel();
         let commit_thread = thread::spawn(move || {
             // This mirrors Worker::append_entry ordering: clear in-flight first,
-            // then publish the finalized AssistantItem. AssistantItem entries
-            // are mirror-only and are not delivered as live entry events.
+            // then publish the finalized AssistantItem. Identity-aware clients
+            // reconcile this durable commit with the preceding streamed block.
             in_flight_for_commit.clear_for_committed_item_then(&assistant_item, || {
                 sink_for_commit.publish(assistant_entry);
             });
@@ -639,7 +639,10 @@ mod tests {
             in_flight_snapshot.blocks.as_slice(),
             [InFlightBlock::Text { text, finished: true }] if text == "done"
         ));
-        assert!(entry_rx.try_recv().is_err());
+        assert!(matches!(
+            entry_rx.try_recv(),
+            Ok(LogEntry::AnnotatedAssistantItem { .. })
+        ));
         let post_commit_guard = in_flight.snapshot_guard();
         assert!(snapshot_from_guard(&post_commit_guard).is_empty());
     }

crates/worker/src/ipc/protocol_session.rs

@@ -34,7 +34,41 @@ pub fn live_log_entry_event(entry: LogEntry) -> Option<Event> {
                 session_store::public_snapshot::project_current_session_snapshot(&[entry]);
             Some(Event::SegmentRotated { session })
         }
-        LogEntry::AnnotatedUserInput { segments, .. } => Some(Event::UserMessage { segments }),
+        LogEntry::AnnotatedUserInput {
+            ts,
+            segments,
+            history,
+            extensions,
+        } => {
+            let projected = session_store::public_snapshot::project_current_session_snapshot(&[
+                LogEntry::AnnotatedUserInput {
+                    ts,
+                    segments: segments.clone(),
+                    history,
+                    extensions,
+                },
+            ]);
+            let entry_id = projected
+                .entries
+                .iter()
+                .find(|entry| {
+                    matches!(
+                        entry.data,
+                        protocol::SessionSnapshotEntryData::UserInput { .. }
+                    )
+                })
+                .map(|entry| entry.entry_id.clone());
+            Some(Event::UserMessage { entry_id, segments })
+        }
+        entry
+        @ (LogEntry::AnnotatedAssistantItem { .. } | LogEntry::AnnotatedToolResult { .. }) => {
+            let mut projected =
+                session_store::public_snapshot::project_current_session_snapshot(&[entry]);
+            projected
+                .entries
+                .pop()
+                .map(|entry| Event::SessionEntryCommitted { entry })
+        }
         LogEntry::AnnotatedSystemItem { entry, .. } => {
             let value = serde_json::to_value(&entry.item).expect("SystemItem is Serialize");
             Some(Event::SystemItem { item: value })
@@ -94,7 +128,9 @@ mod tests {
         .expect("UserInput must be live-relevant");
 
         match event {
-            Event::UserMessage { segments: echoed } => assert_eq!(echoed, segments),
+            Event::UserMessage {
+                segments: echoed, ..
+            } => assert_eq!(echoed, segments),
             other => panic!("expected UserMessage, got {other:?}"),
         }
     }

crates/worker/src/segment_log_sink.rs

@@ -92,14 +92,11 @@ impl SegmentLogSink {
     ///   - `LogEntry::AnnotatedSegmentStart` → `Event::SegmentRotated` on the wire.
     ///   - `LogEntry::AnnotatedUserInput`    → `Event::UserMessage`.
     ///   - `LogEntry::AnnotatedSystemItem`   → `Event::SystemItem`.
+    ///   - assistant/tool commits            → `Event::SessionEntryCommitted`.
     ///   - `LogEntry::Invoke`       → `Event::InvokeStart`.
-    /// Everything else (AssistantItem, ToolResult, TurnEnd,
-    /// RunCompleted, RunErrored, PausedTurnAbandoned, LlmUsage, Extension,
-    /// ConfigChanged) is reflected in the mirror so reconnect snapshots stay accurate,
-    /// but is not sent live — the streaming events (TextDelta /
-    /// ToolCallStart / ToolResult / TurnEnd / etc.) already provide
-    /// that data, and re-broadcasting it as a typed entry would just
-    /// double-render every block on the client side.
+    /// Operational checkpoints remain mirror-only. Assistant/tool streaming
+    /// events are still the in-flight authority; the committed-entry event adds
+    /// the durable stable identity needed to reconcile retained history.
     pub fn publish(&self, entry: LogEntry) {
         let mut mirror = self
             .inner
@@ -122,6 +119,8 @@ impl SegmentLogSink {
             entry,
             LogEntry::AnnotatedSegmentStart { .. }
                 | LogEntry::AnnotatedUserInput { .. }
+                | LogEntry::AnnotatedAssistantItem { .. }
+                | LogEntry::AnnotatedToolResult { .. }
                 | LogEntry::AnnotatedSystemItem { .. }
                 | LogEntry::Invoke { .. }
         )

crates/workspace-server/Cargo.toml

@@ -50,7 +50,10 @@ zeroize.workspace = true
 webauthn-rs = { workspace = true }
 
 [dev-dependencies]
+agen.workspace = true
 tempfile.workspace = true
+tools.workspace = true
+yoi = { path = "../yoi" }
 tower = { workspace = true, features = ["util"] }
 tokio = { workspace = true, features = ["macros", "rt-multi-thread"] }
 webauthn-authenticator-rs = { version = "0.5.5", default-features = false, features = ["softpasskey"] }

crates/workspace-server/src/hosts.rs

@@ -1188,6 +1188,19 @@ pub trait WorkspaceWorkerRuntime: Send + Sync {
         })
     }
 
+    fn worker_session_history(
+        &self,
+        _workspace_id: &str,
+        _worker_ref: &EmbeddedWorkerRef,
+        _cursor: Option<String>,
+        _limit: Option<usize>,
+    ) -> Result<runtime_api::WorkerSessionHistoryAvailability, String> {
+        Ok(runtime_api::WorkerSessionHistoryAvailability::Unavailable {
+            reason: runtime_api::WorkerSessionHistoryUnavailableReason::Unsupported,
+            message: "session history paging is not supported by this Runtime".to_string(),
+        })
+    }
+
     fn observation_source(
         &self,
         _worker_id: &str,
@@ -2017,6 +2030,31 @@ impl RuntimeRegistry {
             })
     }
 
+    pub fn worker_session_history(
+        &self,
+        workspace_id: &str,
+        worker: &RuntimeWorkerRef,
+        cursor: Option<String>,
+        limit: Option<usize>,
+    ) -> Result<runtime_api::WorkerSessionHistoryAvailability, RuntimeRegistryError> {
+        validate_backend_identifier("runtime_id", &worker.runtime_id)?;
+        validate_backend_identifier("worker_id", &worker.worker_id)?;
+        let runtime = self.runtime(&worker.runtime_id)?;
+        let worker_ref =
+            EmbeddedWorkerRef::new(EmbeddedWorkerId::parse(&worker.worker_id).ok_or_else(
+                || RuntimeRegistryError::UnknownWorker {
+                    worker: worker.clone(),
+                },
+            )?);
+        runtime
+            .worker_session_history(workspace_id, &worker_ref, cursor, limit)
+            .map_err(|message| RuntimeRegistryError::RuntimeOperationFailed {
+                runtime_id: worker.runtime_id.clone(),
+                code: "worker_session_history_failed".to_string(),
+                message,
+            })
+    }
+
     pub fn observation_source(
         &self,
         worker: &RuntimeWorkerRef,
@@ -2909,6 +2947,19 @@ impl WorkspaceWorkerRuntime for EmbeddedWorkerRuntime {
             .map_err(|error| error.to_string())
     }
 
+    fn worker_session_history(
+        &self,
+        workspace_id: &str,
+        worker_ref: &EmbeddedWorkerRef,
+        cursor: Option<String>,
+        limit: Option<usize>,
+    ) -> Result<runtime_api::WorkerSessionHistoryAvailability, String> {
+        let scope = RuntimeWorkspaceScope::new(workspace_id, "embedded-backend");
+        self.runtime
+            .worker_session_history_scoped(&scope, worker_ref, cursor, limit)
+            .map_err(|error| error.to_string())
+    }
+
     fn observation_source(
         &self,
         worker_id: &str,
@@ -4924,6 +4975,27 @@ impl WorkspaceWorkerRuntime for RemoteWorkerRuntime {
         .map_err(|diagnostic| diagnostic.message)
     }
 
+    fn worker_session_history(
+        &self,
+        workspace_id: &str,
+        worker_ref: &EmbeddedWorkerRef,
+        cursor: Option<String>,
+        limit: Option<usize>,
+    ) -> Result<runtime_api::WorkerSessionHistoryAvailability, String> {
+        let worker_id = worker_ref.worker_id.to_string();
+        let request = runtime_api::WorkerSessionHistoryRequest {
+            workspace_id: workspace_id.to_string(),
+            cursor,
+            limit,
+        };
+        self.run_runtime_api(
+            self.request_timeout,
+            MAX_REMOTE_RUNTIME_RESPONSE_BYTES,
+            move |client| async move { client.worker_session_history(worker_id, request).await },
+        )
+        .map_err(|diagnostic| diagnostic.message)
+    }
+
     fn observation_source(
         &self,
         worker_id: &str,

crates/yoi/src/lib.rs

@@ -0,0 +1 @@
+pub mod workdir_share;

crates/yoi/src/main.rs

@@ -4,10 +4,11 @@ mod objective_cli;
 mod plugin_cli;
 mod session_cli;
 mod ticket_cli;
-mod workdir_share;
 mod worker_cleanup_cli;
 mod workspace_bootstrap;
 
+use yoi::workdir_share;
+
 use std::collections::BTreeMap;
 use std::fmt;
 use std::fs;
@@ -623,7 +624,7 @@ fn parse_workdir_args(
     let mut ttl = None;
     let mut read_only = false;
     let mut read_write = false;
-    let mut explicit_permissions: Option<server_api::ExternalWorkdirPermissions> = None;
+    let mut explicit_permission_level = None;
     let mut non_interactive = false;
     let mut index = 0;
     while index < args.len() {
@@ -668,29 +669,22 @@ fn parse_workdir_args(
                 index += 2;
             }
             "--permission" => {
-                let category = required_option_value(args, index, "--permission")?;
-                let permissions =
-                    explicit_permissions.get_or_insert(server_api::ExternalWorkdirPermissions {
-                        read: false,
-                        write: false,
-                        command: false,
-                    });
-                let enabled = match category.to_ascii_lowercase().as_str() {
-                    "read" => &mut permissions.read,
-                    "write" => &mut permissions.write,
-                    "command" => &mut permissions.command,
+                let level = required_option_value(args, index, "--permission")?;
+                if explicit_permission_level.is_some() {
+                    return Err(ParseError(
+                        "--permission selects one level and may only be provided once".to_string(),
+                    ));
+                }
+                explicit_permission_level = Some(match level.to_ascii_lowercase().as_str() {
+                    "read" => server_api::ExternalWorkdirPermissionLevel::Read,
+                    "write" => server_api::ExternalWorkdirPermissionLevel::Write,
+                    "command" => server_api::ExternalWorkdirPermissionLevel::Command,
                     _ => {
                         return Err(ParseError(format!(
-                            "unknown --permission category `{category}`; expected read, write, or command"
+                            "unknown --permission level `{level}`; expected read, write, or command"
                         )));
                     }
-                };
-                if *enabled {
-                    return Err(ParseError(format!(
-                        "--permission {category} may only be provided once"
-                    )));
-                }
-                *enabled = true;
+                });
                 index += 2;
             }
             "--read-only" => {
@@ -742,21 +736,18 @@ fn parse_workdir_args(
             "--read-only conflicts with --read-write".to_string(),
         ));
     }
-    if explicit_permissions.is_some() && (read_only || read_write) {
+    if explicit_permission_level.is_some() && (read_only || read_write) {
         return Err(ParseError(
             "--permission conflicts with legacy --read-only/--read-write".to_string(),
         ));
     }
-    let permissions = explicit_permissions.unwrap_or(server_api::ExternalWorkdirPermissions {
-        read: true,
-        write: read_write,
-        command: false,
+    let permissions = explicit_permission_level
+        .map(server_api::ExternalWorkdirPermissionLevel::permissions)
+        .unwrap_or(if read_write {
+            server_api::ExternalWorkdirPermissions::WRITE
+        } else {
+            server_api::ExternalWorkdirPermissions::READ
         });
-    if permissions.write && !permissions.read {
-        return Err(ParseError(
-            "--permission write requires --permission read for read-before-write".to_string(),
-        ));
-    }
     if non_interactive && workspace_id.is_none() {
         return Err(ParseError(
             "--non-interactive requires --workspace-id".to_string(),
@@ -1900,7 +1891,7 @@ Usage:
   yoi --backend <URL> [--workspace-id <ID>] panel
   yoi [--backend <URL>] init --display-name <NAME> --repository-key <KEY> [--repository <PATH>] [--default-ref <REF>]
   yoi [--backend <URL>] login [--no-wait]
-  yoi [--backend <URL>] workdir share <PATH> [--workspace-id <ID>] [--permission <read|write|command>]... [--read-only|--read-write] [--ttl <TTL>] [--display-name <NAME>] [--non-interactive]
+  yoi [--backend <URL>] workdir share <PATH> [--workspace-id <ID>] [--permission <read|write|command>] [--read-only|--read-write] [--ttl <TTL>] [--display-name <NAME>] [--non-interactive]
   yoi <HOST_COMMAND> [OPTIONS]
 
 Target selection:
@@ -1946,7 +1937,7 @@ Options:
 
 fn print_workdir_help() {
     println!(
-        "yoi workdir share\n\nUsage:\n  yoi [--backend <URL>] workdir share <PATH> [OPTIONS]\n\nThe foreground CLI provides one local directory over an authenticated outbound Backend connection.\nInteractive mode is the default: choose an accessible Workspace, READ/WRITE/COMMAND categories, and TTL, then explicitly confirm before any grant is created.\nREAD enables Read/Glob/Grep and related observation operations. WRITE enables Write/Edit and requires READ for read-before-write. COMMAND is independent, disabled by default, and runs with the sharing CLI user's host authority; it is not sandboxed.\nRepeat --permission to choose explicit categories in automation. Legacy --read-only and --read-write remain file-only aliases and conflict with --permission.\nOmitting --ttl means unlimited automatic lifetime, but stop, disconnect, Ctrl-C, and revoke still fail closed. TTL accepts s, m, or h suffixes from 60s through 24h.\nNo host path is sent to the Backend. Ctrl-C explicitly revokes the grant before exit.\n\nOptions:\n      --workspace-id <ID>  Preselect a Workspace; required with --non-interactive\n      --permission <CATEGORY>  Enable read, write, or command; repeat per category\n      --read-only          Legacy alias for --permission read\n      --read-write         Legacy alias for read + write (commands remain disabled)\n      --ttl <TTL>          Automatic expiry; omission is unlimited\n      --display-name <NAME>  Backend-visible label (default: External Workdir)\n      --non-interactive    Never prompt; requires --workspace-id\n  -h, --help               Print help\n"
+        "yoi workdir share\n\nUsage:\n  yoi [--backend <URL>] workdir share <PATH> [OPTIONS]\n\nThe foreground CLI provides one local directory over an authenticated outbound Backend connection.\nInteractive mode is the default: choose an accessible Workspace, one READ/WRITE/COMMAND permission level, and TTL, then explicitly confirm before any grant is created.\nREAD enables Read/Glob/Grep and related observation operations. WRITE includes READ and adds Write/Edit. COMMAND includes WRITE and READ, adds command start/status/output/cancel, and runs with the sharing CLI user's host authority; it is not sandboxed.\nUse --permission once to choose the level in automation. Legacy --read-only and --read-write retain the READ and WRITE meanings and conflict with --permission.\nOmitting --ttl means unlimited automatic lifetime, but stop, disconnect, Ctrl-C, and revoke still fail closed. TTL accepts s, m, or h suffixes from 60s through 24h.\nNo host path is sent to the Backend. Ctrl-C explicitly revokes the grant before exit.\n\nOptions:\n      --workspace-id <ID>  Preselect a Workspace; required with --non-interactive\n      --permission <LEVEL>  Grant read, write (includes read), or command (includes write + read)\n      --read-only          Legacy alias for --permission read\n      --read-write         Legacy alias for --permission write\n      --ttl <TTL>          Automatic expiry; omission is unlimited\n      --display-name <NAME>  Backend-visible label (default: External Workdir)\n      --non-interactive    Never prompt; requires --workspace-id\n  -h, --help               Print help\n"
     );
 }
 
@@ -2038,7 +2029,7 @@ mod tests {
     }
 
     #[test]
-    fn workdir_share_parses_independent_command_permission() {
+    fn workdir_share_parses_command_as_the_full_hierarchical_level() {
         let args = vec![
             "share".to_string(),
             ".".to_string(),
@@ -2056,11 +2047,7 @@ mod tests {
         };
         assert_eq!(
             options.permissions,
-            server_api::ExternalWorkdirPermissions {
-                read: false,
-                write: false,
-                command: true,
-            }
+            server_api::ExternalWorkdirPermissions::COMMAND
         );
     }
 
@@ -2131,17 +2118,19 @@ mod tests {
                 .contains("conflicts")
         );
 
-        let write_without_read = vec![
+        let multiple_levels = vec![
             "share".to_string(),
             ".".to_string(),
             "--permission".to_string(),
             "write".to_string(),
+            "--permission".to_string(),
+            "command".to_string(),
         ];
         assert!(
-            parse_workdir_args(&write_without_read, &target)
+            parse_workdir_args(&multiple_levels, &target)
                 .unwrap_err()
                 .0
-                .contains("requires --permission read")
+                .contains("selects one level")
         );
 
         let missing_workspace = TargetSelection {

crates/yoi/src/workdir_share.rs

@@ -25,7 +25,7 @@ use workdir::{
 };
 
 #[derive(Debug, Clone, PartialEq, Eq)]
-pub(crate) struct WorkdirShareOptions {
+pub struct WorkdirShareOptions {
     pub path: PathBuf,
     pub workspace_id: Option<String>,
     pub backend_url: String,
@@ -37,6 +37,39 @@ pub(crate) struct WorkdirShareOptions {
 
 const PROVIDER_OPERATION_TIMEOUT: Duration = Duration::from_secs(30);
 
+fn validate_provider_registration(message: Message, generation: u64) -> Result<(), String> {
+    let registered = match message {
+        Message::Text(text) => text,
+        Message::Close(Some(frame)) => {
+            let reason = frame.reason.trim();
+            return Err(if reason.is_empty() {
+                "Backend rejected the External Workdir provider registration".to_string()
+            } else {
+                format!("Backend rejected the External Workdir provider registration: {reason}")
+            });
+        }
+        Message::Close(None) => {
+            return Err("Backend rejected the External Workdir provider registration".to_string());
+        }
+        _ => {
+            return Err(
+                "Backend returned an invalid External Workdir registration frame".to_string(),
+            );
+        }
+    };
+    let frame = serde_json::from_str::<ExternalWorkdirServerFrame>(&registered)
+        .map_err(|error| format!("Backend returned an invalid External Workdir frame: {error}"))?;
+    if matches!(
+        frame.message,
+        ExternalWorkdirServerMessage::Registered { generation: registered_generation, .. }
+            if registered_generation == generation
+    ) {
+        Ok(())
+    } else {
+        Err("Backend rejected the External Workdir provider registration".to_string())
+    }
+}
+
 fn provider_operation_timeout(operation: &workdir::http::WorkdirSessionOperation) -> Duration {
     if matches!(
         operation,
@@ -49,7 +82,7 @@ fn provider_operation_timeout(operation: &workdir::http::WorkdirSessionOperation
 }
 
 #[derive(Debug, Clone, Copy, PartialEq, Eq)]
-enum ProviderEnd {
+pub enum ProviderEnd {
     Disconnected,
     Revoked,
     Interrupted,
@@ -140,47 +173,42 @@ fn authenticated_server_api_client(
     Ok(ServerApiClient::with_client(base_url, http_client))
 }
 
-fn permissions_label(permissions: server_api::ExternalWorkdirPermissions) -> String {
-    let mut enabled = Vec::new();
-    if permissions.read {
-        enabled.push("READ");
+fn permissions_label(permissions: server_api::ExternalWorkdirPermissions) -> &'static str {
+    match permissions.grant_level() {
+        Some(server_api::ExternalWorkdirPermissionLevel::Read) => "READ",
+        Some(server_api::ExternalWorkdirPermissionLevel::Write) => "WRITE (includes READ)",
+        Some(server_api::ExternalWorkdirPermissionLevel::Command) => {
+            "COMMAND (includes WRITE + READ)"
         }
-    if permissions.write {
-        enabled.push("WRITE");
+        None => "INVALID",
     }
-    if permissions.command {
-        enabled.push("COMMAND");
-    }
-    enabled.join(", ")
 }
 
 fn validate_permissions(permissions: server_api::ExternalWorkdirPermissions) -> Result<(), String> {
-    if permissions.write && !permissions.read {
+    if permissions.grant_level().is_none() {
         return Err(
-            "WRITE requires READ so existing files can satisfy read-before-write; select both categories"
+            "select exactly one permission level: READ, WRITE (includes READ), or COMMAND (includes WRITE + READ)"
                 .to_string(),
         );
     }
-    if !permissions.read && !permissions.command {
-        return Err("select at least one of READ or COMMAND".to_string());
-    }
     Ok(())
 }
 
 fn workdir_capabilities(
     permissions: server_api::ExternalWorkdirPermissions,
 ) -> workdir::WorkdirSessionCapabilities {
-    let mut capabilities = workdir::WorkdirSessionCapabilities::EMPTY;
-    if permissions.read {
-        capabilities = capabilities.union(workdir::WorkdirSessionCapabilities::READ_ONLY);
+    match permissions.grant_level() {
+        Some(server_api::ExternalWorkdirPermissionLevel::Read) => {
+            workdir::WorkdirSessionCapabilities::READ_ONLY
         }
-    if permissions.write {
-        capabilities = capabilities.union(workdir::WorkdirSessionCapabilities::WRITE_ONLY);
+        Some(server_api::ExternalWorkdirPermissionLevel::Write) => {
+            workdir::WorkdirSessionCapabilities::READ_WRITE
         }
-    if permissions.command {
-        capabilities = capabilities.union(workdir::WorkdirSessionCapabilities::COMMAND_ONLY);
+        Some(server_api::ExternalWorkdirPermissionLevel::Command) => {
+            workdir::WorkdirSessionCapabilities::ALL
+        }
+        None => workdir::WorkdirSessionCapabilities::EMPTY,
     }
-    capabilities
 }
 
 #[derive(Debug, Clone, PartialEq, Eq)]
@@ -193,7 +221,7 @@ struct ResolvedWorkdirShareOptions {
     permissions: server_api::ExternalWorkdirPermissions,
 }
 
-pub(crate) fn parse_ttl(value: &str) -> Result<Duration, String> {
+pub fn parse_ttl(value: &str) -> Result<Duration, String> {
     let (number, multiplier) = if let Some(value) = value.strip_suffix('h') {
         (value, 60 * 60)
     } else if let Some(value) = value.strip_suffix('m') {
@@ -302,14 +330,14 @@ fn configure_interactively(
 
     writeln!(
         output,
-        "Permissions are independent categories: READ (Read/Glob/Grep), WRITE (Write/Edit), and COMMAND (host command lifecycle). WRITE requires READ for read-before-write. COMMAND runs with this CLI user's host authority and is not sandboxed."
+        "Permission levels: READ (Read/Glob/Grep), WRITE (includes READ + Write/Edit), or COMMAND (includes WRITE + READ + host command lifecycle). COMMAND runs with this CLI user's host authority and is not sandboxed."
     )
     .map_err(|error| format!("failed to write prompt: {error}"))?;
     let Some(permission_input) = read_prompt_line(
         input,
         output,
         &format!(
-            "Permissions [comma-separated READ/WRITE/COMMAND; current {}; q to cancel]: ",
+            "Permission level [READ/WRITE/COMMAND; current {}; q to cancel]: ",
             permissions_label(options.permissions)
         ),
     )?
@@ -320,28 +348,20 @@ fn configure_interactively(
         return Ok(None);
     }
     if !permission_input.is_empty() {
-        let mut permissions = server_api::ExternalWorkdirPermissions {
-            read: false,
-            write: false,
-            command: false,
-        };
-        for category in permission_input
-            .split([',', ' '])
-            .filter(|category| !category.is_empty())
-        {
-            match category.to_ascii_lowercase().as_str() {
-                "r" | "read" | "read-only" | "read_only" => permissions.read = true,
-                "w" | "write" | "read-write" | "read_write" => permissions.write = true,
-                "c" | "command" => permissions.command = true,
+        options.permissions = match permission_input.to_ascii_lowercase().as_str() {
+            "r" | "read" | "read-only" | "read_only" => {
+                server_api::ExternalWorkdirPermissions::READ
+            }
+            "w" | "write" | "read-write" | "read_write" => {
+                server_api::ExternalWorkdirPermissions::WRITE
+            }
+            "c" | "command" => server_api::ExternalWorkdirPermissions::COMMAND,
             _ => {
                 return Err(format!(
-                        "unknown permission category `{category}`; use READ, WRITE, or COMMAND"
+                    "unknown permission level `{permission_input}`; use READ, WRITE, or COMMAND"
                 ));
             }
-            }
-        }
-        validate_permissions(permissions)?;
-        options.permissions = permissions;
+        };
     }
 
     writeln!(output, "TTL: {}", ttl_label(options.ttl))
@@ -437,7 +457,7 @@ async fn resolve_share_options(
     configure_interactively(options, &workspaces, &mut input, &mut output)
 }
 
-pub(crate) async fn run(options: WorkdirShareOptions) -> Result<(), String> {
+pub async fn run(options: WorkdirShareOptions) -> Result<(), String> {
     let Some(options) = resolve_share_options(options).await? else {
         eprintln!("External Workdir share cancelled; no grant was created.");
         return Ok(());
@@ -649,7 +669,7 @@ async fn serve_provider_connection(
         .max_message_size(Some(workdir::external::MAX_EXTERNAL_SERVER_FRAME_BYTES))
         .max_frame_size(Some(workdir::external::MAX_EXTERNAL_SERVER_FRAME_BYTES));
     let connection = connect_async_with_config(request, Some(websocket_config), false);
-    let (mut socket, _) = tokio::select! {
+    let (socket, _) = tokio::select! {
         signal = tokio::signal::ctrl_c() => {
             signal.map_err(|error| format!("failed to wait for Ctrl-C: {error}"))?;
             revoke(server_api_client, &options.workspace_id, &grant.grant_id).await?;
@@ -671,11 +691,40 @@ async fn serve_provider_connection(
                 read_limits: BoundedReadLimits::EXTERNAL_DEFAULT,
             },
         });
+    let end =
+        serve_external_workdir_provider_socket(socket, registration, session, generation, async {
+            tokio::signal::ctrl_c()
+                .await
+                .map_err(|error| format!("failed to wait for Ctrl-C: {error}"))
+        })
+        .await?;
+    if end == ProviderEnd::Interrupted {
+        revoke(server_api_client, &options.workspace_id, &grant.grant_id).await?;
+    }
+    Ok(end)
+}
+
+/// Run the production External Workdir provider protocol over an established WebSocket.
+///
+/// The CLI uses this pump after opening its authenticated Backend connection. Keeping the
+/// protocol pump separate lets composed tests exercise the same registration, operation,
+/// cancellation, and result-forwarding implementation without spawning a second CLI process.
+pub async fn serve_external_workdir_provider_socket<S, I>(
+    mut socket: tokio_tungstenite::WebSocketStream<S>,
+    registration: ExternalWorkdirProviderFrame,
+    session: &LocalWorkdirSession,
+    generation: u64,
+    interrupt: I,
+) -> Result<ProviderEnd, String>
+where
+    S: tokio::io::AsyncRead + tokio::io::AsyncWrite + Unpin,
+    I: std::future::Future<Output = Result<(), String>>,
+{
+    tokio::pin!(interrupt);
     send_provider_frame(&mut socket, &registration).await?;
     let registered = tokio::select! {
-        signal = tokio::signal::ctrl_c() => {
-            signal.map_err(|error| format!("failed to wait for Ctrl-C: {error}"))?;
-            revoke(server_api_client, &options.workspace_id, &grant.grant_id).await?;
+        signal = &mut interrupt => {
+            signal?;
             return Ok(ProviderEnd::Interrupted);
         }
         registered = tokio::time::timeout(Duration::from_secs(10), socket.next()) => {
@@ -685,18 +734,7 @@ async fn serve_provider_connection(
                 .map_err(|error| format!("External Workdir provider registration failed: {error}"))?
         }
     };
-    let Message::Text(registered) = registered else {
-        return Err("Backend returned an invalid External Workdir registration frame".to_string());
-    };
-    let frame = serde_json::from_str::<ExternalWorkdirServerFrame>(&registered)
-        .map_err(|error| format!("Backend returned an invalid External Workdir frame: {error}"))?;
-    if !matches!(
-        frame.message,
-        ExternalWorkdirServerMessage::Registered { generation: registered_generation, .. }
-            if registered_generation == generation
-    ) {
-        return Err("Backend rejected the External Workdir provider registration".to_string());
-    }
+    validate_provider_registration(registered, generation)?;
     println!("Connection: online (generation {generation})");
 
     let (completion_sender, mut completions) =
@@ -704,10 +742,9 @@ async fn serve_provider_connection(
     let mut operations = HashMap::<String, OperationTask>::new();
     loop {
         tokio::select! {
-            signal = tokio::signal::ctrl_c() => {
-                signal.map_err(|error| format!("failed to wait for Ctrl-C: {error}"))?;
+            signal = &mut interrupt => {
+                signal?;
                 stop_provider_operations(session, &mut operations, &mut completions).await?;
-                revoke(server_api_client, &options.workspace_id, &grant.grant_id).await?;
                 return Ok(ProviderEnd::Interrupted);
             }
             completion = completions.recv() => {
@@ -916,7 +953,7 @@ async fn execute_operation(
             Ok(result) => ExternalWorkdirOperationOutcome::Completed { result },
             Err(message) => ExternalWorkdirOperationOutcome::Failed {
                 error: ExternalWorkdirOperationError::from_transport_error(WorkdirTransportError {
-                    code: workdir::http::WorkdirTransportErrorCode::Unsupported,
+                    code: workdir::http::WorkdirTransportErrorCode::InvalidRequest,
                     message,
                 }),
             },
@@ -1060,6 +1097,23 @@ mod tests {
         }
     }
 
+    #[test]
+    fn provider_registration_surfaces_backend_close_reason() {
+        use tokio_tungstenite::tungstenite::protocol::CloseFrame;
+        use tokio_tungstenite::tungstenite::protocol::frame::coding::CloseCode;
+
+        let error = validate_provider_registration(
+            Message::Close(Some(CloseFrame {
+                code: CloseCode::Policy,
+                reason: "provider read limits source=1024 response=512; Backend requires source=2048 response=1024".into(),
+            })),
+            1,
+        )
+        .unwrap_err();
+        assert!(error.contains("provider read limits"), "{error}");
+        assert!(error.contains("Backend requires"), "{error}");
+    }
+
     #[test]
     fn interactive_share_defaults_to_first_workspace_read_only_and_unlimited() {
         let workspaces = [workspace("workspace-a", "Alpha")];
@@ -1085,12 +1139,12 @@ mod tests {
     }
 
     #[test]
-    fn interactive_share_requires_explicit_write_and_command_selection_and_confirmation() {
+    fn interactive_share_selects_one_hierarchical_level_and_requires_confirmation() {
         let workspaces = [
             workspace("workspace-a", "Alpha"),
             workspace("workspace-b", "Beta"),
         ];
-        let mut input = std::io::Cursor::new(b"2\nREAD,WRITE,COMMAND\n15m\ny\n".to_vec());
+        let mut input = std::io::Cursor::new(b"2\nCOMMAND\n15m\ny\n".to_vec());
         let mut output = Vec::new();
 
         let selected =
@@ -1110,7 +1164,39 @@ mod tests {
         assert_eq!(selected.ttl, Some(Duration::from_secs(900)));
         let output = String::from_utf8(output).unwrap();
         assert!(output.contains("not sandboxed"));
-        assert!(output.contains("Permissions: READ, WRITE, COMMAND"));
+        assert!(output.contains("Permissions: COMMAND (includes WRITE + READ)"));
+    }
+
+    #[test]
+    fn share_permission_levels_map_to_exact_existing_capability_bits() {
+        let bits = |permissions| {
+            serde_json::to_value(workdir_capabilities(permissions)).unwrap()["bits"]
+                .as_u64()
+                .unwrap()
+        };
+        assert_eq!(bits(server_api::ExternalWorkdirPermissions::READ), 25);
+        assert_eq!(bits(server_api::ExternalWorkdirPermissions::WRITE), 31);
+        assert_eq!(bits(server_api::ExternalWorkdirPermissions::COMMAND), 63);
+
+        for invalid in [
+            server_api::ExternalWorkdirPermissions {
+                read: false,
+                write: false,
+                command: true,
+            },
+            server_api::ExternalWorkdirPermissions {
+                read: false,
+                write: true,
+                command: false,
+            },
+            server_api::ExternalWorkdirPermissions {
+                read: true,
+                write: false,
+                command: true,
+            },
+        ] {
+            assert!(validate_permissions(invalid).is_err());
+        }
     }
 
     #[test]

docs/development/external-workdir-sharing.md

@@ -1,34 +1,49 @@
 # External Workdir sharing permissions
 
 `yoi workdir share` exposes a client-hosted directory through an authenticated,
-outbound Backend connection. The operator grants three independent categories:
+outbound Backend connection. The operator selects exactly one permission level:
 
-- **READ**: file reads and read-only discovery operations such as Stat, List,
-  ViewImage, Glob, and Grep.
-- **WRITE**: Write and Edit. WRITE requires READ because updating an existing
-  file uses the read-before-write content-hash contract. Selecting WRITE never
-  enables COMMAND.
-- **COMMAND**: command start, status, bounded output, and cancellation. COMMAND
-  does not enable READ or WRITE. It executes on the sharing host with the OS
+- **READ** (capability bits `25`): file reads and read-only discovery operations
+  such as Stat, List, ViewImage, Glob, and Grep.
+- **WRITE** (capability bits `31`): READ plus Write and Edit. Including READ
+  preserves the read-before-write content-hash contract. WRITE never enables
+  COMMAND.
+- **COMMAND** (capability bits `63`): WRITE plus READ plus command start, status,
+  bounded output, and cancellation. It executes on the sharing host with the OS
   authority of the user running the CLI; External Workdir command execution is
   **not a sandbox** and does not confine the process to the shared directory.
 
-READ is enabled by default and COMMAND is disabled by default. Interactive mode
-asks for a comma-separated category list and shows the exact grant before it is
-created. For automation, repeat `--permission`:
+In short, `COMMAND ⇒ WRITE ⇒ READ`. READ is the default. Interactive mode asks
+for one level and shows its included permissions before creating the grant. For
+automation, pass `--permission` once:
 
 ```sh
 yoi --backend https://example.invalid workdir share ./project \
   --workspace-id workspace-a \
-  --permission read \
-  --permission write \
   --permission command \
   --non-interactive
 ```
 
-`--read-only` remains an alias for READ. `--read-write` remains an alias for
-READ+WRITE and never enables COMMAND. These legacy flags conflict with explicit
-`--permission` arguments so ambiguous automation fails closed.
+`--read-only` remains an alias for the READ level. `--read-write` remains an
+alias for the WRITE level and never enables COMMAND. These legacy flags conflict
+with `--permission`, and multiple `--permission` arguments are rejected so
+ambiguous automation fails closed.
+
+The grant API retains the boolean projection for compatibility, but accepts only
+these combinations when creating new grants:
+
+| Level | `read` | `write` | `command` |
+|---|---:|---:|---:|
+| READ | `true` | `false` | `false` |
+| WRITE | `true` | `true` | `false` |
+| COMMAND | `true` | `true` | `true` |
+
+Older non-hierarchical grants such as command-only or READ+COMMAND are not
+silently widened. The Backend refuses their projection, provider registration,
+and subsequent restore/reconnect with guidance to revoke and re-share the
+directory at one of the supported levels. General Workdir attachment/session
+capability intersections may still produce partial capability sets; that
+restriction applies only to External grant authority.
 
 Omitting `--ttl` creates no automatic expiry. An explicit TTL must be between
 60 seconds and 24 hours. Ctrl-C, revoke, expiry, provider disconnect, attachment

openapi/server-api.json

@@ -2092,15 +2092,15 @@
         "additionalProperties": false,
         "properties": {
           "command": {
-            "description": "Execute commands as the sharing CLI user on the provider host. This is\nexplicit authority and does not imply either filesystem category.",
+            "description": "Execute commands as the sharing CLI user on the provider host. COMMAND\nincludes WRITE and READ, remains explicit, and is not sandboxed.",
             "type": "boolean"
           },
           "read": {
-            "description": "Read files and use read-only discovery operations such as Glob and Grep.",
+            "description": "Read files and use read-only discovery operations such as Glob and Grep.\nEvery supported External Workdir permission level enables this field.",
             "type": "boolean"
           },
           "write": {
-            "description": "Create or update files with Write and Edit. Existing-file mutation also\nrequires `read` so callers can satisfy the read-before-write contract.",
+            "description": "Create or update files with Write and Edit. WRITE includes READ so callers\ncan satisfy the read-before-write contract.",
             "type": "boolean"
           }
         },
@@ -14020,7 +14020,7 @@
   "info": {
     "title": "Yoi Server API",
     "version": "0.1.0",
-    "x-yoi-source-digest": "sha256:3a298734fd19f3a224e4f1503385fb8a823b612d328224f45f677ebaca28b96c"
+    "x-yoi-source-digest": "sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0"
   },
   "openapi": "3.1.0",
   "paths": {

tools/web-ux/browser-tests/console_history_fixture_server.ts

@@ -0,0 +1,224 @@
+import { extname, join, normalize } from "jsr:@std/path@1.1.4";
+
+const port = Number(Deno.args[0]);
+const buildRoot = Deno.args[1];
+if (!Number.isInteger(port) || !buildRoot) {
+  throw new Error("usage: console_history_fixture_server.ts <port> <build-root>");
+}
+
+const workspaceId = "console-history-review";
+const runtimeId = "runtime-a";
+const workerId = "worker-a";
+const workerResourceKey = "W-900";
+let historyRequests = 0;
+
+const json = (value: unknown, status = 200) =>
+  new Response(JSON.stringify(value), {
+    status,
+    headers: { "content-type": "application/json; charset=utf-8" },
+  });
+
+const worker = {
+  worker_id: workerId,
+  runtime_id: runtimeId,
+  resource_key: workerResourceKey,
+  display_name: "Console Fixture",
+  label: "Console Fixture",
+  availability: "observed",
+  state: "stopped",
+  retention_state: "retained",
+  host_id: "fixture-host",
+  profile: "default",
+  tags: [],
+  diagnostics: [],
+  capabilities: { can_stop: false, can_spawn_followup: false },
+  workspace: {
+    workspace_id: workspaceId,
+    visibility: "workspace",
+    identity: workspaceId,
+  },
+  implementation: { kind: "builtin", display_hint: "fixture" },
+  workdir_attachments: [],
+};
+
+function historyEntry(index: number, role: "user" | "assistant") {
+  const user = role === "user";
+  return {
+    entry_id: `${role}-${index}`,
+    timestamp: index,
+    provenance: user ? "human_input" : "model_output",
+    kind: "message",
+    role,
+    content: [{
+      kind: "text",
+      text: user
+        ? `question ${index}`
+        : `done ${index}\ndetail ${index}.1\ndetail ${index}.2\ndetail ${index}.3`,
+    }],
+  };
+}
+
+function historyPage(indices: number[], cursor: string | null) {
+  return {
+    availability: "page",
+    page: {
+      session_id: "session-a",
+      lineage_id: "lineage-a",
+      compact_ancestor_lineage_ids: [],
+      turns: indices.map((index) => ({
+        turn_id: `user-${index}`,
+        entries: [historyEntry(index, "user"), historyEntry(index, "assistant")],
+      })),
+      next_cursor: cursor,
+      has_more: cursor !== null,
+    },
+  };
+}
+
+const mime: Record<string, string> = {
+  ".html": "text/html; charset=utf-8",
+  ".js": "text/javascript; charset=utf-8",
+  ".css": "text/css; charset=utf-8",
+  ".json": "application/json; charset=utf-8",
+  ".svg": "image/svg+xml",
+  ".png": "image/png",
+  ".woff2": "font/woff2",
+};
+
+async function staticResponse(pathname: string): Promise<Response> {
+  const relative = pathname === "/" ? "index.html" : pathname.replace(/^\/+/, "");
+  const normalized = normalize(relative);
+  if (normalized.startsWith("..")) return new Response("not found", { status: 404 });
+  let filePath = join(buildRoot, normalized);
+  try {
+    const stat = await Deno.stat(filePath);
+    if (stat.isDirectory) filePath = join(filePath, "index.html");
+    return new Response(await Deno.readFile(filePath), {
+      headers: { "content-type": mime[extname(filePath)] ?? "application/octet-stream" },
+    });
+  } catch {
+    return new Response(await Deno.readFile(join(buildRoot, "index.html")), {
+      headers: { "content-type": "text/html; charset=utf-8" },
+    });
+  }
+}
+
+Deno.serve({ hostname: "127.0.0.1", port }, async (request) => {
+  const url = new URL(request.url);
+  if (url.pathname === "/health") return new Response("ok");
+  if (url.pathname === "/fixture-state") return json({ history_requests: historyRequests });
+  if (url.pathname === "/api/workspaces") {
+    return json([{
+      workspace_id: workspaceId,
+      owner_account_id: "owner",
+      display_name: "Console History Review",
+      state: "active",
+      created_at: "2026-01-01T00:00:00Z",
+      updated_at: "2026-01-02T00:00:00Z",
+    }]);
+  }
+  if (url.pathname === `/api/w/${workspaceId}/workspace`) {
+    return json({
+      workspace_id: workspaceId,
+      display_name: "Console History Review",
+      record_authority: "fixture",
+      schema_version: 1,
+      auth: {
+        Passkey: {
+          rp_id: "127.0.0.1",
+          origin: `http://127.0.0.1:${port}`,
+          public_base_url: `http://127.0.0.1:${port}`,
+          cookie_name: "fixture",
+        },
+      },
+      permissions: {
+        manage_repositories: false,
+        manage_secrets: false,
+        manage_runtimes: false,
+        delete_workspace: false,
+      },
+      extension_points: {
+        store: "fixture",
+        event_stream: { status: "ready", note: "fixture", diagnostics: [] },
+        host_worker_bridge: { status: "ready", note: "fixture", diagnostics: [] },
+        companion_console: { status: "ready", note: "fixture", diagnostics: [] },
+      },
+    });
+  }
+  if (url.pathname === `/api/w/${workspaceId}/repositories`) {
+    return json({ workspace_id: workspaceId, items: [], source: "fixture", diagnostics: [] });
+  }
+  if (url.pathname === `/api/w/${workspaceId}/working-directories`) {
+    return json({ workspace_id: workspaceId, items: [], diagnostics: [] });
+  }
+  if (
+    url.pathname === `/api/w/${workspaceId}/workers/${workerResourceKey}` ||
+    url.pathname === `/api/w/${workspaceId}/runtimes/${runtimeId}/workers/${workerId}`
+  ) {
+    return json(worker);
+  }
+  if (
+    url.pathname ===
+      `/api/w/${workspaceId}/runtimes/${runtimeId}/workers/${workerId}/session`
+  ) {
+    return json({
+      availability: "retained_snapshot",
+      identity: { session_id: "session-a", segment_id: "segment-a", entry_count: 12 },
+      snapshot: {
+        pending_submissions: {
+          revision: 0,
+          notification_count: 0,
+          head_id: null,
+          submissions: [],
+        },
+        entries: [7, 8, 9, 10, 11, 12].flatMap((index) => [
+          historyEntry(index, "user"),
+          historyEntry(index, "assistant"),
+        ]),
+      },
+    });
+  }
+  if (
+    url.pathname ===
+      `/api/w/${workspaceId}/runtimes/${runtimeId}/workers/${workerId}/session/history`
+  ) {
+    historyRequests += 1;
+    switch (url.searchParams.get("cursor")) {
+      case null:
+        return json(historyPage([8, 9, 10, 11, 12], "older-8"));
+      case "older-8":
+        return json(historyPage([3, 4, 5, 6, 7], "older-3"));
+      case "older-3":
+        return json(historyPage([1, 2], null));
+      default:
+        return json({ availability: "unavailable", reason: "invalid_cursor", message: "invalid" });
+    }
+  }
+  if (
+    url.pathname === `/api/w/${workspaceId}/protocol/ws` &&
+    request.headers.get("upgrade") === "websocket"
+  ) {
+    const { socket, response } = Deno.upgradeWebSocket(request);
+    socket.onmessage = (event) => {
+      const frame = JSON.parse(String(event.data));
+      if (frame?.message?.method !== "subscribe_events") return;
+      const requestId = frame.message.params.request_id;
+      socket.send(JSON.stringify({
+        protocol_version: 1,
+        frame: "response",
+        message: {
+          result: "subscribed",
+          payload: {
+            request_id: requestId,
+            subscription_id: "fixture-workers",
+            selector: frame.message.params.selector,
+            snapshot_revision: 1,
+            snapshot: { topic: "workers", data: { workers: [] } },
+          },
+        },
+      }));
+    };
+    return response;
+  }
+  return await staticResponse(url.pathname);
+});

tools/web-ux/browser-tests/console_history_shell_test.ts

@@ -0,0 +1,217 @@
+import { assert, assertEquals } from "@std/assert";
+import { dirname, fromFileUrl, join } from "@std/path";
+import { chromium } from "playwright";
+
+const repositoryRoot = join(dirname(fromFileUrl(import.meta.url)), "../../..");
+const workspaceRoot = join(repositoryRoot, "web/workspace");
+const fixtureServer = join(
+  repositoryRoot,
+  "tools/web-ux/browser-tests/console_history_fixture_server.ts",
+);
+const workspaceId = "console-history-review";
+
+async function freePort(): Promise<number> {
+  const listener = Deno.listen({ hostname: "127.0.0.1", port: 0 });
+  const port = (listener.addr as Deno.NetAddr).port;
+  listener.close();
+  return port;
+}
+
+async function waitForServer(url: string): Promise<void> {
+  for (let attempt = 0; attempt < 200; attempt += 1) {
+    try {
+      if ((await fetch(url)).ok) return;
+    } catch {
+      // Retry until the bounded deadline while the owned server starts.
+    }
+    await new Promise((resolve) => setTimeout(resolve, 50));
+  }
+  throw new Error(`fixture server did not become ready: ${url}`);
+}
+
+async function historyRequestCount(baseUrl: string): Promise<number> {
+  const response = await fetch(`${baseUrl}/fixture-state`);
+  const state = await response.json();
+  return state.history_requests;
+}
+
+Deno.test("production Console pages backward by real turns while preserving both scroll anchors", async () => {
+  const build = await new Deno.Command(Deno.execPath(), {
+    args: ["task", "build"],
+    cwd: workspaceRoot,
+    stdout: "piped",
+    stderr: "piped",
+  }).output();
+  if (!build.success) {
+    throw new Error(
+      `Workspace production build failed:\n${new TextDecoder().decode(build.stderr)}`,
+    );
+  }
+
+  const port = await freePort();
+  const baseUrl = `http://127.0.0.1:${port}`;
+  const server = new Deno.Command(Deno.execPath(), {
+    args: [
+      "run",
+      "--allow-net",
+      "--allow-read",
+      fixtureServer,
+      String(port),
+      join(workspaceRoot, "build"),
+    ],
+    stdout: "null",
+    stderr: "null",
+  }).spawn();
+
+  try {
+    await waitForServer(`${baseUrl}/health`);
+    const browser = await chromium.launch({ headless: true });
+    try {
+      const context = await browser.newContext({
+        viewport: { width: 1440, height: 600 },
+        colorScheme: "dark",
+      });
+      const page = await context.newPage();
+      const errors: string[] = [];
+      const responses: string[] = [];
+      page.on("console", (message) => {
+        if (message.type() === "error") errors.push(message.text());
+      });
+      page.on("pageerror", (error) => errors.push(String(error)));
+      page.on("response", (response) => {
+        if (response.status() >= 400 || response.url().includes("/api/")) {
+          responses.push(`${response.status()} ${response.url()}`);
+        }
+      });
+
+      await page.goto(
+        `${baseUrl}/w/${workspaceId}/workers/W-900-console-fixture/console`,
+      );
+      const transcript = page.getByRole("article", { name: "main transcript" });
+      try {
+        await transcript.getByText("question 8", { exact: true }).waitFor({ timeout: 5_000 });
+      } catch (error) {
+        throw new Error(
+          `Console did not render retained history: ${error}\nresponses=${
+            JSON.stringify(responses)
+          }\nerrors=${JSON.stringify(errors)}\nbody=${await page.locator("body").innerText()}`,
+        );
+      }
+      const navigation = page.getByRole("complementary", { name: "Conversation turns" });
+      await navigation.getByText("question 7", { exact: true }).waitFor();
+      assertEquals(await historyRequestCount(baseUrl), 1);
+      assertEquals(await transcript.getByText(/^question (7|8|9|10|11|12)$/).count(), 6);
+      assertEquals(await navigation.getByText(/^question (7|8|9|10|11|12)$/).count(), 6);
+      const currentQuestionTop = await transcript
+        .getByText("question 7", { exact: true })
+        .evaluate((element) => element.getBoundingClientRect().top);
+      const retainedQuestionTop = await transcript
+        .getByText("question 8", { exact: true })
+        .evaluate((element) => element.getBoundingClientRect().top);
+      assert(
+        currentQuestionTop < retainedQuestionTop,
+        "the unmatched current-snapshot turn must precede overlapping retained history",
+      );
+
+      const question12 = navigation.getByRole("button", {
+        name: "Jump to conversation: question 12",
+      });
+      assertEquals(await question12.getByText("detail 12.1", { exact: true }).count(), 1);
+      assertEquals(await question12.getByText("detail 12.2", { exact: true }).count(), 1);
+      assertEquals(await question12.getByText("detail 12.3", { exact: true }).count(), 0);
+      assert(!(await question12.textContent())?.includes("User"));
+      assert(!(await question12.textContent())?.includes("AI"));
+
+      const consoleScroll = transcript.locator("xpath=..");
+      const topAlignment = await page.evaluate(() => {
+        const document = (globalThis as any).document;
+        const body = document.querySelector(".console-scroll")?.getBoundingClientRect();
+        const turns = document.querySelector(".turn-navigation")?.getBoundingClientRect();
+        return body && turns ? Math.abs(body.top - turns.top) : Number.POSITIVE_INFINITY;
+      });
+      assert(topAlignment <= 1, `transcript and turn bar top edges differ by ${topAlignment}px`);
+
+      const navigationAnchoredTop = await navigation
+        .locator('[data-turn-id="user-8"]')
+        .evaluate((element) => element.getBoundingClientRect().top);
+      const anchoredTop = await consoleScroll.evaluate((element) => {
+        element.scrollTop = 0;
+        const anchor = element.querySelector('[data-console-line-id*="user-8"]');
+        const top = anchor?.getBoundingClientRect().top ?? Number.NaN;
+        element.dispatchEvent(new Event("scroll"));
+        return top;
+      });
+      await transcript.getByText("question 3", { exact: true }).waitFor();
+      await navigation.getByText("question 3", { exact: true }).waitFor();
+      const restoredTop = await transcript
+        .locator('[data-console-line-id*="user-8"]')
+        .evaluate((element) => element.getBoundingClientRect().top);
+      assert(
+        Math.abs(restoredTop - anchoredTop) <= 1,
+        `transcript anchor moved from ${anchoredTop}px to ${restoredTop}px`,
+      );
+      await page.waitForTimeout(250);
+      assertEquals(
+        await historyRequestCount(baseUrl),
+        2,
+        "a stationary top sentinel must not drain another page",
+      );
+
+      const turnList = navigation.locator(".turn-list");
+      const navigationAfterPrepend = await navigation
+        .locator('[data-turn-id="user-8"]')
+        .evaluate((element) => element.getBoundingClientRect().top);
+      assert(
+        Math.abs(navigationAfterPrepend - navigationAnchoredTop) <= 1,
+        `turn-bar anchor moved from ${navigationAnchoredTop}px to ${navigationAfterPrepend}px`,
+      );
+      await turnList.evaluate((element) => {
+        element.scrollTop = Math.max(2, element.scrollTop);
+        element.dispatchEvent(new Event("scroll"));
+        element.scrollTop = 0;
+        element.dispatchEvent(new Event("scroll"));
+      });
+      await transcript.getByText("question 1", { exact: true }).waitFor();
+      await navigation.getByText("question 1", { exact: true }).waitFor();
+      assertEquals(await historyRequestCount(baseUrl), 3);
+      assertEquals(await page.getByText("Start of conversation", { exact: true }).count(), 2);
+
+      await navigation.getByRole("button", {
+        name: "Jump to conversation: question 3",
+      }).click();
+      await page.waitForFunction(() => {
+        const document = (globalThis as any).document;
+        const element = document.querySelector('[data-console-line-id*="user-3"]');
+        const parent = element?.closest(".console-scroll");
+        if (!element || !parent) return false;
+        const item = element.getBoundingClientRect();
+        const viewport = parent.getBoundingClientRect();
+        return item.top >= viewport.top - 1 && item.top < viewport.bottom;
+      });
+      const jumpGeometry = await transcript
+        .locator('[data-console-line-id*="user-3"]')
+        .evaluate((element) => {
+          const parent = element.closest(".console-scroll")!;
+          const item = element.getBoundingClientRect();
+          const viewport = parent.getBoundingClientRect();
+          return { itemTop: item.top, viewportTop: viewport.top, viewportBottom: viewport.bottom };
+        });
+      assert(jumpGeometry.itemTop >= jumpGeometry.viewportTop - 1);
+      assert(jumpGeometry.itemTop < jumpGeometry.viewportBottom);
+
+      const centering = await question12.evaluate((button) => {
+        const turn = button.getBoundingClientRect();
+        const bar = button.querySelector(".bar")!.getBoundingClientRect();
+        return Math.abs((turn.top + turn.bottom) / 2 - (bar.top + bar.bottom) / 2);
+      });
+      assert(centering <= 1, `turn marker is not vertically centered (${centering}px)`);
+      assertEquals(errors, []);
+      await context.close();
+    } finally {
+      await browser.close();
+    }
+  } finally {
+    server.kill("SIGTERM");
+    await server.status;
+  }
+});

tools/web-ux/browser-tests/memory_document_fixture_server.ts

@@ -0,0 +1,149 @@
+import { extname, join, normalize } from "jsr:@std/path@1.1.4";
+
+const port = Number(Deno.args[0]);
+const buildRoot = Deno.args[1];
+const sectionCount = Deno.args[2] === undefined ? 90 : Number(Deno.args[2]);
+if (
+  !Number.isInteger(port) || !buildRoot || !Number.isInteger(sectionCount) || sectionCount < 3 ||
+  sectionCount > 100
+) {
+  throw new Error("usage: server.ts <port> <build-root> [section-count: 3..100]");
+}
+
+const workspaceId = "memory-review";
+const paragraphs = Array.from(
+  { length: sectionCount },
+  (_, index) =>
+    `## Section ${
+      index + 1
+    }\n\nThis is representative Memory content with **important context**, an identifier \`memory-item-${
+      index + 1
+    }\`, and a long URL https://example.com/${"long-segment-".repeat(12)}${
+      index + 1
+    }.\n\n> A durable note for section ${index + 1}.\n\n- first detail\n- second detail`,
+).join("\n\n");
+const bodyMd =
+  `# Workspace Memory\n\nThis document is read-only.\n\n| Very wide heading | Another heading | Decision |\n| --- | --- | --- |\n| ${
+    "wide-value-".repeat(16)
+  } | stable | keep scrolling local |\n\n##### Deep document heading\n\n###### Deepest document heading\n\n\`\`\`rust\nfn example() { println!("${
+    "wide-code-".repeat(18)
+  }"); }\n\`\`\`\n\n[Safe link](https://example.com) [Unsafe link](javascript:alert(1))\n\n<img src=x onerror=alert(1)>\n\n${paragraphs}\n\n## T-661 UNIQUE END MARKER`;
+
+const json = (value: unknown, status = 200) =>
+  new Response(JSON.stringify(value), {
+    status,
+    headers: { "content-type": "application/json; charset=utf-8" },
+  });
+
+const mime: Record<string, string> = {
+  ".html": "text/html; charset=utf-8",
+  ".js": "text/javascript; charset=utf-8",
+  ".css": "text/css; charset=utf-8",
+  ".json": "application/json; charset=utf-8",
+  ".svg": "image/svg+xml",
+  ".png": "image/png",
+  ".woff2": "font/woff2",
+};
+
+async function staticResponse(pathname: string): Promise<Response> {
+  const relative = pathname === "/" ? "index.html" : pathname.replace(/^\/+/, "");
+  const normalized = normalize(relative);
+  if (normalized.startsWith("..")) return new Response("not found", { status: 404 });
+  let filePath = join(buildRoot, normalized);
+  try {
+    const stat = await Deno.stat(filePath);
+    if (stat.isDirectory) filePath = join(filePath, "index.html");
+    return new Response(await Deno.readFile(filePath), {
+      headers: { "content-type": mime[extname(filePath)] ?? "application/octet-stream" },
+    });
+  } catch {
+    return new Response(await Deno.readFile(join(buildRoot, "index.html")), {
+      headers: { "content-type": "text/html; charset=utf-8" },
+    });
+  }
+}
+
+Deno.serve({ hostname: "127.0.0.1", port }, async (request) => {
+  const url = new URL(request.url);
+  if (url.pathname === "/health") return new Response("ok");
+  if (url.pathname === "/api/workspaces") {
+    return json([{
+      workspace_id: workspaceId,
+      owner_account_id: "owner",
+      display_name: "Memory Review",
+      state: "active",
+      created_at: "2026-01-01T00:00:00Z",
+      updated_at: "2026-01-02T00:00:00Z",
+    }]);
+  }
+  if (url.pathname === `/api/w/${workspaceId}/workspace`) {
+    return json({
+      workspace_id: workspaceId,
+      display_name: "Memory Review",
+      record_authority: "fixture",
+      schema_version: 1,
+      auth: {
+        Passkey: {
+          rp_id: "127.0.0.1",
+          origin: `http://127.0.0.1:${port}`,
+          public_base_url: `http://127.0.0.1:${port}`,
+          cookie_name: "fixture",
+        },
+      },
+      permissions: {
+        manage_repositories: false,
+        manage_secrets: false,
+        manage_runtimes: false,
+        delete_workspace: false,
+      },
+      extension_points: {
+        store: "fixture",
+        event_stream: { status: "ready", note: "fixture", diagnostics: [] },
+        host_worker_bridge: { status: "ready", note: "fixture", diagnostics: [] },
+        companion_console: { status: "ready", note: "fixture", diagnostics: [] },
+      },
+    });
+  }
+  if (url.pathname === `/api/w/${workspaceId}/repositories`) {
+    return json({ workspace_id: workspaceId, items: [], source: "fixture", diagnostics: [] });
+  }
+  if (url.pathname === `/api/w/${workspaceId}/working-directories`) {
+    return json({ workspace_id: workspaceId, items: [], diagnostics: [] });
+  }
+  if (url.pathname === `/api/w/${workspaceId}/memory`) {
+    return json({
+      body_md: bodyMd,
+      created_at: "2026-01-01T00:00:00Z",
+      updated_at: "2026-01-02T03:04:05Z",
+      bytes: new TextEncoder().encode(bodyMd).byteLength,
+      record_source: "sqlite_workspace_authority.memory_document",
+    });
+  }
+  if (
+    url.pathname === `/api/w/${workspaceId}/protocol/ws` &&
+    request.headers.get("upgrade") === "websocket"
+  ) {
+    const { socket, response } = Deno.upgradeWebSocket(request);
+    socket.onmessage = (event) => {
+      const frame = JSON.parse(String(event.data));
+      if (frame?.message?.method !== "subscribe_events") return;
+      const requestId = frame.message.params.request_id;
+      socket.send(JSON.stringify({
+        protocol_version: 1,
+        frame: "response",
+        message: {
+          result: "subscribed",
+          payload: {
+            request_id: requestId,
+            subscription_id: "fixture-workers",
+            selector: { topic: "workspace_workers" },
+            snapshot_revision: 1,
+            snapshot: { topic: "workers", data: { workers: [] } },
+          },
+        },
+      }));
+    };
+    return response;
+  }
+  return await staticResponse(url.pathname);
+});

tools/web-ux/browser-tests/memory_document_shell_test.ts

@@ -0,0 +1,251 @@
+import { assert, assertEquals } from "@std/assert";
+import { dirname, fromFileUrl, join } from "@std/path";
+import { chromium, type Page } from "playwright";
+
+const repositoryRoot = join(dirname(fromFileUrl(import.meta.url)), "../../..");
+const workspaceRoot = join(repositoryRoot, "web/workspace");
+const fixtureServer = join(
+  repositoryRoot,
+  "tools/web-ux/browser-tests/memory_document_fixture_server.ts",
+);
+const workspaceId = "memory-review";
+
+async function freePort(): Promise<number> {
+  const listener = Deno.listen({ hostname: "127.0.0.1", port: 0 });
+  const port = (listener.addr as Deno.NetAddr).port;
+  listener.close();
+  return port;
+}
+
+async function waitForServer(url: string): Promise<void> {
+  for (let attempt = 0; attempt < 200; attempt += 1) {
+    try {
+      if ((await fetch(url)).ok) return;
+    } catch {
+      // Retry until the bounded deadline while the owned server starts.
+    }
+    await new Promise((resolve) => setTimeout(resolve, 50));
+  }
+  throw new Error(`fixture server did not become ready: ${url}`);
+}
+
+async function mainScrollState(page: Page) {
+  return await page.locator("main").evaluate((main) => ({
+    scrollTop: main.scrollTop,
+    scrollHeight: main.scrollHeight,
+    clientHeight: main.clientHeight,
+  }));
+}
+
+async function markerIsInsideMain(page: Page): Promise<boolean> {
+  return await page.evaluate(() => {
+    const document = (globalThis as any).document;
+    const main = document.querySelector("main");
+    const marker = [...document.querySelectorAll("h2")].find((heading) =>
+      heading.textContent === "T-661 UNIQUE END MARKER"
+    );
+    if (!main || !marker) return false;
+    const mainRect = main.getBoundingClientRect();
+    const markerRect = marker.getBoundingClientRect();
+    return markerRect.top >= mainRect.top && markerRect.bottom <= mainRect.bottom;
+  });
+}
+
+async function openMemoryPage(
+  page: Page,
+  baseUrl: string,
+  mobile = false,
+): Promise<void> {
+  await page.goto(`${baseUrl}/w/${workspaceId}/memory`);
+  const heading = page.locator("h1", { hasText: "Workspace Memory" });
+  await heading.waitFor({ state: "attached" });
+  if (mobile) await page.getByRole("button", { name: "Hide sidebar" }).click();
+  await heading.waitFor();
+}
+
+async function swipeMainToEnd(page: Page): Promise<void> {
+  const session = await page.context().newCDPSession(page);
+  for (let attempt = 0; attempt < 100; attempt += 1) {
+    const state = await mainScrollState(page);
+    if (state.scrollTop + state.clientHeight >= state.scrollHeight - 1) return;
+    await session.send("Input.dispatchTouchEvent", {
+      type: "touchStart",
+      touchPoints: [{ x: 300, y: 700, id: 1 }],
+    });
+    for (const y of [580, 460, 340, 220, 100]) {
+      await session.send("Input.dispatchTouchEvent", {
+        type: "touchMove",
+        touchPoints: [{ x: 300, y, id: 1 }],
+      });
+    }
+    await session.send("Input.dispatchTouchEvent", {
+      type: "touchEnd",
+      touchPoints: [],
+    });
+    await page.waitForTimeout(20);
+  }
+  throw new Error("touch input did not reach the end of the Memory document");
+}
+
+Deno.test("production Memory shell renders safe Markdown and scrolls to its end by wheel, keyboard, and touch", async () => {
+  const build = await new Deno.Command(Deno.execPath(), {
+    args: ["task", "build"],
+    cwd: workspaceRoot,
+    stdout: "piped",
+    stderr: "piped",
+  }).output();
+  if (!build.success) {
+    throw new Error(
+      `Workspace production build failed:\n${new TextDecoder().decode(build.stderr)}`,
+    );
+  }
+
+  const port = await freePort();
+  const baseUrl = `http://127.0.0.1:${port}`;
+  const server = new Deno.Command(Deno.execPath(), {
+    args: [
+      "run",
+      "--allow-net",
+      "--allow-read",
+      fixtureServer,
+      String(port),
+      join(workspaceRoot, "build"),
+    ],
+    stdout: "null",
+    stderr: "null",
+  }).spawn();
+
+  try {
+    await waitForServer(`${baseUrl}/health`);
+    const browser = await chromium.launch({ headless: true });
+    try {
+      for (
+        const scenario of [
+          { label: "wheel", width: 1440, height: 900, colorScheme: "light" as const },
+          { label: "keyboard", width: 768, height: 900, colorScheme: "dark" as const },
+          {
+            label: "touch",
+            width: 390,
+            height: 844,
+            colorScheme: "light" as const,
+            mobile: true,
+          },
+        ]
+      ) {
+        const context = await browser.newContext({
+          viewport: { width: scenario.width, height: scenario.height },
+          colorScheme: scenario.colorScheme,
+          hasTouch: scenario.mobile ?? false,
+          isMobile: scenario.mobile ?? false,
+        });
+        const page = await context.newPage();
+        const errors: string[] = [];
+        page.on("console", (message) => {
+          if (message.type() === "error") errors.push(message.text());
+        });
+        page.on("pageerror", (error) => errors.push(String(error)));
+        await openMemoryPage(page, baseUrl, scenario.mobile);
+
+        const initial = await mainScrollState(page);
+        assert(initial.scrollHeight > initial.clientHeight);
+        assertEquals(await markerIsInsideMain(page), false);
+        assertEquals(
+          await page.evaluate(() => {
+            const document = (globalThis as any).document;
+            return document.documentElement.scrollWidth === document.documentElement.clientWidth;
+          }),
+          true,
+        );
+
+        if (scenario.label === "wheel") {
+          assertEquals(await page.locator("h1").allTextContents(), ["Workspace Memory"]);
+          assertEquals(
+            await page.locator("strong").filter({ hasText: "important context" }).count() > 0,
+            true,
+          );
+          assertEquals(await page.locator("blockquote").count() > 0, true);
+          assertEquals(await page.locator("ul li").count() > 0, true);
+          for (
+            const heading of [
+              { selector: "h5", text: "Deep document heading" },
+              { selector: "h6", text: "Deepest document heading" },
+            ]
+          ) {
+            const element = page.locator(heading.selector, { hasText: heading.text });
+            assertEquals(await element.count(), 1);
+            assert(
+              await element.evaluate((node) =>
+                Number.parseFloat((globalThis as any).getComputedStyle(node).fontSize) >= 12
+              ),
+              `${heading.selector} fell below the design language minimum text size`,
+            );
+          }
+          assertEquals(await page.locator('a[href="https://example.com"]').count(), 1);
+          assertEquals(await page.locator('a[href^="javascript:"]').count(), 0);
+          assertEquals(await page.locator("article img, article script").count(), 0);
+          assertEquals(await page.getByRole("heading", { name: "Memory Document" }).count(), 0);
+
+          for (const label of ["Markdown table", "rust code block"]) {
+            const region = page.getByRole("region", { name: label });
+            assertEquals(await region.getAttribute("tabindex"), "0");
+            assert(await region.evaluate((element) => element.scrollWidth > element.clientWidth));
+          }
+
+          await page.locator("main").hover();
+          await page.mouse.wheel(0, 100_000);
+        } else if (scenario.label === "keyboard") {
+          await page.getByText("Document details", { exact: true }).focus();
+          await page.keyboard.press("End");
+        } else {
+          await swipeMainToEnd(page);
+        }
+
+        await page.waitForTimeout(500);
+        const afterInteraction = await mainScrollState(page);
+        assert(
+          afterInteraction.scrollTop > 0,
+          `${scenario.label} did not move the main scroll owner: ${
+            JSON.stringify(afterInteraction)
+          }`,
+        );
+        assertEquals(await markerIsInsideMain(page), true);
+        assertEquals(errors, []);
+        await context.close();
+      }
+
+      const stateContext = await browser.newContext({ viewport: { width: 1440, height: 900 } });
+      const emptyPage = await stateContext.newPage();
+      await emptyPage.route(`**/api/w/${workspaceId}/memory`, async (route) => {
+        await route.fulfill({
+          contentType: "application/json",
+          body: JSON.stringify({
+            body_md: " \n",
+            created_at: "2026-01-01T00:00:00Z",
+            updated_at: "2026-01-02T03:04:05Z",
+            bytes: 2,
+            record_source: "fixture",
+          }),
+        });
+      });
+      await emptyPage.goto(`${baseUrl}/w/${workspaceId}/memory`);
+      await emptyPage.getByText("Memory document is empty.").waitFor();
+      assertEquals(await emptyPage.getByRole("alert").count(), 0);
+
+      const errorPage = await stateContext.newPage();
+      await errorPage.route(`**/api/w/${workspaceId}/memory`, async (route) => {
+        await route.fulfill({ status: 503, contentType: "application/json", body: "{}" });
+      });
+      await errorPage.goto(`${baseUrl}/w/${workspaceId}/memory`);
+      const alert = errorPage.getByRole("alert");
+      await alert.waitFor();
+      assert((await alert.textContent())?.includes("Memory document unavailable."));
+      assertEquals(await errorPage.getByText("Memory document is empty.").count(), 0);
+      await stateContext.close();
+    } finally {
+      await browser.close();
+    }
+  } finally {
+    server.kill("SIGTERM");
+    await server.status;
+  }
+});

tools/web-ux/deno.json

@@ -11,7 +11,7 @@
     "web-ux": "deno run --allow-env --allow-net --allow-read --allow-write --allow-run --allow-sys cli.ts",
     "check": "deno check cli.ts src/*.ts tests/*.ts browser-tests/*.ts",
     "test": "deno test --allow-env --allow-read --allow-write --allow-run --allow-sys tests",
-    "test:browser": "deno test --allow-env --allow-net --allow-read --allow-write --allow-run --allow-sys browser-tests/capture_smoke_test.ts"
+    "test:browser": "deno test --allow-env --allow-net --allow-read --allow-write --allow-run --allow-sys browser-tests/capture_smoke_test.ts browser-tests/memory_document_shell_test.ts browser-tests/console_history_shell_test.ts"
   },
   "fmt": {
     "lineWidth": 100,

web/workspace/README.md

@@ -96,6 +96,7 @@ Use semantic tokens from `app.css`. Do not introduce component-local color, spac
 - `src/routes/w/[workspaceId]/settings/+layout.svelte`: Settings Sidebar registration.
 - `src/lib/workspace/header/`: Header frame, context, and overrides.
 - `src/lib/workspace/sidebar/`: Sidebar frame, scoped content, contexts, and override stack.
+- `src/lib/workspace/markdown/`: shared safe Markdown parsing plus presentation-specific document renderers.
 - `src/lib/workspace/ui/`: generic presentation components such as `Tooltip`, `Bevel`, and `BevelLine`.
 - `src/routes/design-lab/workspace-web-ux/`: static Design Language showroom.
 

web/workspace/deno.json

@@ -6,7 +6,7 @@
     "dev": "deno run -A npm:vite@7.2.7 dev",
     "dev:backend": "cd ../.. && cargo run -p yoi-workspace-server --bin yoi-server -- serve --listen 127.0.0.1:8787",
     "check": "deno run -A npm:@sveltejs/kit@2.49.4 sync && deno run -A npm:svelte-check@4.3.4 --tsconfig ./tsconfig.json",
-    "test": "deno test --allow-read=src,test,tests,../../docs --allow-env=LOG,VSCODE_TEXTMATE_DEBUG,NODE_ENV tests/workspace-model.test.ts tests/repository-api.test.ts tests/workspace-catalog.test.ts tests/profile-api.test.ts tests/skill-api.test.ts tests/tooltip-contract.test.ts tests/bevel-contract.test.ts tests/bevel-line-contract.test.ts tests/typography-contract.test.ts src/lib/workspace/auth/model.test.ts src/lib/workspace/protocol-validator.test.ts tests/auth-api.test.ts src/lib/workspace/api/http.test.ts src/lib/workspace/api/workers.test.ts src/lib/workspace/api/ticket-browser.test.ts src/lib/workspace/header/breadcrumb-model.test.ts src/lib/workspace/console/chat-submit.test.ts src/lib/workspace/console/composer-delivery.test.ts test/composer-history.test.ts tests/composer-paste.test.ts src/lib/workspace/console/composer-command.test.ts src/lib/workspace/console/composer-draft.test.ts src/lib/workspace/console/composer-completion.test.ts test/console/ansi.test.ts src/lib/workspace/console/model.test.ts src/lib/workspace/console/turn-navigation.test.ts src/lib/workspace/console/run-status.test.ts src/lib/workspace/companion/api.test.ts tests/workdir-api.test.ts tests/workdir-permissions.test.ts src/lib/workspace/console/tasks.test.ts test/ticket-detail-route-reuse.test.ts test/spa-shell.test.ts test/objective-pages.test.ts test/repositories/ui.test.ts src/lib/workspace/console/worker-console.ui.test.ts src/lib/workspace/settings/model.test.ts tests/runtime-connection.test.ts tests/runtime-management.test.ts tests/runtime-management-source.test.ts src/lib/workspace/sidebar/override-stack.test.ts src/lib/workspace/sidebar/route-ownership.test.ts src/lib/workspace/sidebar/workers.test.ts src/lib/workspace/sidebar/workspace-switcher.test.ts src/lib/workspace/sidebar/worker-subscription.test.ts src/lib/workspace/sidebar/worker-workdir-meta.test.ts src/lib/workspace/sidebar/worker-launch.test.ts test/sidebar/worker-actions.test.ts src/lib/workspace/tickets/merge-request-resources.test.ts src/lib/workspace/tickets/ticket-panel.test.ts test/merge-request-status.test.ts test/config-source/decodal-grammar.test.ts test/config-source/editor-state.test.ts test/config-source/fixed-schema-wrapper.test.ts test/config-source/toolchain.test.ts test/config-source/wasm-parity.test.ts test/config-source/api.test.ts tests/memory-api.test.ts test/repository-access/api.test.ts test/repository-access/loader.test.ts test/repository-access/model.test.ts test/repository-access/structure.test.ts test/repository-ssh-connection-ui.test.ts",
+    "test": "deno test --allow-read=src,test,tests,../../docs --allow-env=LOG,VSCODE_TEXTMATE_DEBUG,NODE_ENV tests/workspace-model.test.ts tests/repository-api.test.ts tests/workspace-catalog.test.ts tests/profile-api.test.ts tests/skill-api.test.ts tests/tooltip-contract.test.ts tests/bevel-contract.test.ts tests/bevel-line-contract.test.ts tests/typography-contract.test.ts src/lib/workspace/auth/model.test.ts src/lib/workspace/protocol-validator.test.ts tests/auth-api.test.ts src/lib/workspace/api/http.test.ts src/lib/workspace/api/workers.test.ts src/lib/workspace/api/ticket-browser.test.ts src/lib/workspace/header/breadcrumb-model.test.ts src/lib/workspace/console/chat-submit.test.ts src/lib/workspace/console/composer-delivery.test.ts test/composer-history.test.ts tests/composer-paste.test.ts src/lib/workspace/console/composer-command.test.ts src/lib/workspace/console/composer-draft.test.ts src/lib/workspace/console/composer-completion.test.ts test/console/ansi.test.ts src/lib/workspace/console/history.test.ts src/lib/workspace/console/model.test.ts src/lib/workspace/console/turn-navigation.test.ts src/lib/workspace/console/run-status.test.ts src/lib/workspace/companion/api.test.ts tests/workdir-api.test.ts tests/workdir-permissions.test.ts src/lib/workspace/console/tasks.test.ts test/ticket-detail-route-reuse.test.ts test/spa-shell.test.ts test/objective-pages.test.ts test/repositories/ui.test.ts src/lib/workspace/console/worker-console.ui.test.ts src/lib/workspace/settings/model.test.ts tests/runtime-connection.test.ts tests/runtime-management.test.ts tests/runtime-management-source.test.ts src/lib/workspace/sidebar/override-stack.test.ts src/lib/workspace/sidebar/route-ownership.test.ts src/lib/workspace/sidebar/workers.test.ts src/lib/workspace/sidebar/workspace-switcher.test.ts src/lib/workspace/sidebar/worker-subscription.test.ts src/lib/workspace/sidebar/worker-workdir-meta.test.ts src/lib/workspace/sidebar/worker-launch.test.ts test/sidebar/worker-actions.test.ts src/lib/workspace/tickets/merge-request-resources.test.ts src/lib/workspace/tickets/ticket-panel.test.ts test/merge-request-status.test.ts test/config-source/decodal-grammar.test.ts test/config-source/editor-state.test.ts test/config-source/fixed-schema-wrapper.test.ts test/config-source/toolchain.test.ts test/config-source/wasm-parity.test.ts test/config-source/api.test.ts tests/memory-api.test.ts test/repository-access/api.test.ts test/repository-access/loader.test.ts test/repository-access/model.test.ts test/repository-access/structure.test.ts test/repository-ssh-connection-ui.test.ts",
     "test:component": "deno run -A npm:vitest@3.2.4 run --config vitest.config.ts",
     "build": "deno run -A npm:vite@7.2.7 build",
     "preview": "deno run -A npm:vite@7.2.7 preview",

web/workspace/src/lib/generated/companion-api.ts

@@ -1,6 +1,6 @@
 // @generated by yoi-companion-openapi-typescript@1. Do not edit.
 // Input: openapi/server-api.json
-// Input contract: 0.1.0 (sha256:3a298734fd19f3a224e4f1503385fb8a823b612d328224f45f677ebaca28b96c)
+// Input contract: 0.1.0 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
 // Options: companion-operation-schema-closure,openapi-3.1,strict-integer-ranges,sorted-output
 // Output: web/workspace/src/lib/generated/companion-api.ts
 // Regenerate/check: cargo run -q -p server-api --example generate_companion_api_types -- --check

web/workspace/src/lib/generated/protocol.ts

@@ -149,6 +149,33 @@ entry_id: string,
  */
 timestamp: number, provenance: SessionEntryProvenance, derived_from?: Array<string>, } & ({ "kind": "user_input", segments: Array<Segment>, } | { "kind": "message", role: SessionMessageRole, content: Array<SessionContentPart>, } | { "kind": "tool_call", call_id: string, name: string, arguments: string, } | { "kind": "tool_result", call_id: string, summary: string, content?: string | null, is_error: boolean, attachments?: Array<SessionToolAttachment>, } | { "kind": "system_item", item_kind: string, content: string, data?: unknown, } | { "kind": "run_error", message: string, });
 
+export type SessionConversationTurn = { turn_id: string, entries: Array<SessionSnapshotEntry>, };
+
+export type SessionHistoryLineageBoundary = { lineage_id: string,
+/**
+ * Canonical public form of the final user-visible turn at the exact
+ * provider boundary. Entries after that boundary are excluded.
+ */
+adopted_through_turn?: SessionConversationTurn | null, };
+
+export type SessionHistoryPage = { session_id: string,
+/**
+ * Stable identity of the adopted active lineage used to fence stale pages.
+ */
+lineage_id: string,
+/**
+ * Older lineage identities that the active lineage fully adopted through
+ * one or more consecutive Compact rotations. Clients may retain already
+ * loaded turns when their prior lineage appears here, while replacing the
+ * cursor with this page's boundary.
+ */
+compact_ancestor_lineage_ids?: Array<string>,
+/**
+ * Immediate parent relationship used to retain only the adopted prefix
+ * across fork/rewind refreshes that have no newest-page overlap.
+ */
+parent_lineage?: SessionHistoryLineageBoundary | null, turns: Array<SessionConversationTurn>, next_cursor?: string | null, has_more: boolean, };
+
 export type PendingSubmissionSummary = { submission_id: string,
 /**
  * Single-line display text, at most 240 Unicode scalars plus an ellipsis.
@@ -306,7 +333,11 @@ export type SubscriptionFrame = { protocol_version: number, } & ({ "frame": "req
 
 export type Method = { "method": "submit", "params": { submission_request_id: string, input: Array<Segment>, } } | { "method": "notify", "params": { notification_request_id: string, message: string, } } | { "method": "worker_event", "params": WorkerEvent } | { "method": "list_pending_submissions" } | { "method": "cancel_pending_submission", "params": { submission_id: string, expected_revision: number, } } | { "method": "clear_pending_submissions", "params": { expected_revision: number, } } | { "method": "continue_pending", "params": { expected_revision: number, expected_head_id: string, } } | { "method": "resume", "params": { command: WorkerCommandEnvelope, } } | { "method": "cancel", "params": { command: WorkerCommandEnvelope, } } | { "method": "pause", "params": { command: WorkerCommandEnvelope, } } | { "method": "compact", "params": { command: WorkerCommandEnvelope, } } | { "method": "list_rewind_targets" } | { "method": "rewind_to", "params": { target: RewindTargetId, expected_head_entries: number, } } | { "method": "shutdown", "params": { command: WorkerCommandEnvelope, } } | { "method": "list_completions", "params": { kind: CompletionKind, prefix: string, } } | { "method": "list_workers" } | { "method": "restore_worker", "params": { name: string, } } | { "method": "register_peer", "params": { name: string, } };
 
-export type Event = { "event": "submission_accepted", "data": { submission_request_id: string, submission_id: string, disposition: SubmissionDisposition, } } | { "event": "submission_rejected", "data": { submission_request_id: string, message: string, } } | { "event": "pending_submissions_changed", "data": { pending: PendingSubmissionsSnapshot, } } | { "event": "user_message", "data": { segments: Array<Segment>, } } | { "event": "system_item", "data": { item: unknown, } } | { "event": "invoke_start", "data": { kind: InvokeKind, } } | { "event": "turn_start", "data": { turn: number, } } | { "event": "turn_end", "data": { turn: number, result: TurnResult, } } | { "event": "llm_call_start", "data": { llm_call: number, } } | { "event": "llm_call_end", "data": { llm_call: number, } } | { "event": "llm_retry", "data": { llm_call: number,
+export type Event = { "event": "submission_accepted", "data": { submission_request_id: string, submission_id: string, disposition: SubmissionDisposition, } } | { "event": "submission_rejected", "data": { submission_request_id: string, message: string, } } | { "event": "pending_submissions_changed", "data": { pending: PendingSubmissionsSnapshot, } } | { "event": "user_message", "data": {
+/**
+ * Stable durable history identity. Older mixed-version producers omit it.
+ */
+entry_id?: string | null, segments: Array<Segment>, } } | { "event": "session_entry_committed", "data": { entry: SessionSnapshotEntry, } } | { "event": "system_item", "data": { item: unknown, } } | { "event": "invoke_start", "data": { kind: InvokeKind, } } | { "event": "turn_start", "data": { turn: number, } } | { "event": "turn_end", "data": { turn: number, result: TurnResult, } } | { "event": "llm_call_start", "data": { llm_call: number, } } | { "event": "llm_call_end", "data": { llm_call: number, } } | { "event": "llm_retry", "data": { llm_call: number,
 /**
  * The attempt that just failed. 1 origin.
  */

web/workspace/src/lib/generated/repository-api.ts

@@ -1,6 +1,6 @@
 // @generated by yoi-repository-openapi-typescript@1. Do not edit.
 // Input: openapi/server-api.json
-// Input contract: 0.1.0 (sha256:3a298734fd19f3a224e4f1503385fb8a823b612d328224f45f677ebaca28b96c)
+// Input contract: 0.1.0 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
 // Options: repository-operation-schema-closure,openapi-3.1,format:uint64=safe-number,strict-safe-integers,sorted-output
 // Output: web/workspace/src/lib/generated/repository-api.ts
 // Regenerate/check: cargo run -q -p server-api --example generate_repository_openapi_types -- --check

web/workspace/src/lib/generated/runtime-api.ts

@@ -1,6 +1,6 @@
 // @generated by yoi-runtime-openapi-typescript@1. Do not edit.
 // Input: openapi/server-api.json
-// Input contract: 0.1.0 (sha256:3a298734fd19f3a224e4f1503385fb8a823b612d328224f45f677ebaca28b96c)
+// Input contract: 0.1.0 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
 // Options: runtime-operation-schema-closure,openapi-3.1,strict-integer-ranges,sorted-output
 // Output: web/workspace/src/lib/generated/runtime-api.ts
 // Regenerate/check: cargo run -q -p server-api --example generate_runtime_api_types -- --check

web/workspace/src/lib/generated/ticket-api.ts

@@ -1,6 +1,6 @@
 // @generated by yoi-ticket-browser-openapi-typescript@1. Do not edit.
 // Input: openapi/server-api.json
-// Input contract: 0.1.0 (sha256:3a298734fd19f3a224e4f1503385fb8a823b612d328224f45f677ebaca28b96c)
+// Input contract: 0.1.0 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
 // Options: ticket-objective-merge-request-browser-operation-schema-closure,openapi-3.1,strict-integer-ranges,sorted-output
 // Output: web/workspace/src/lib/generated/ticket-api.ts
 // Regenerate/check: cargo run -q -p server-api --example generate_ticket_api_types -- --check

web/workspace/src/lib/generated/workdir-api.ts

@@ -1,6 +1,6 @@
 // @generated by yoi-workdir-openapi-typescript@1. Do not edit.
 // Input: openapi/server-api.json
-// Input contract: 0.1.0 (sha256:3a298734fd19f3a224e4f1503385fb8a823b612d328224f45f677ebaca28b96c)
+// Input contract: 0.1.0 (sha256:7b06d005d3436758c96fc4cfd462df76460f89620fd1b58fdf05009d96bb9052)
 // Options: workdir-operation-schema-closure,openapi-3.1,strict-integer-ranges,sorted-output
 // Output: web/workspace/src/lib/generated/workdir-api.ts
 // Regenerate/check: cargo run -q -p server-api --example generate_workdir_api_types -- --check

web/workspace/src/lib/generated/worker-launch-api.ts

@@ -1,6 +1,6 @@
 // @generated by yoi-worker-openapi-typescript@1. Do not edit.
 // Input: openapi/server-api.json
-// Input contract: 0.1.0 (sha256:3a298734fd19f3a224e4f1503385fb8a823b612d328224f45f677ebaca28b96c)
+// Input contract: 0.1.0 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
 // Options: worker-operation-schema-closure,openapi-3.1,strict-integer-ranges,sorted-output
 // Output: web/workspace/src/lib/generated/worker-launch-api.ts
 // Regenerate/check: cargo run -q -p server-api --example generate_worker_launch_api_types -- --check

web/workspace/src/lib/workspace/api/workdirs.ts

@@ -182,7 +182,9 @@ function parseWorkingDirectorySource(value: unknown): WorkingDirectorySource {
   );
   const kind = stringField(source, "kind");
   if (kind === "repository") {
-    if (source.grant_id !== undefined || source.grant_permissions !== undefined) {
+    if (
+      source.grant_id !== undefined || source.grant_permissions !== undefined
+    ) {
       throw new Error(
         "Repository Workdir source must not contain External grant authority",
       );
@@ -201,7 +203,7 @@ function parseWorkingDirectorySource(value: unknown): WorkingDirectorySource {
     return {
       kind,
       grant_id: stringField(source, "grant_id"),
-      grant_permissions: parseExternalWorkdirPermissions(
+      grant_permissions: parseExternalWorkdirGrantPermissions(
         source.grant_permissions,
         "External Workdir grant permissions",
       ),
@@ -226,6 +228,21 @@ export function parseExternalWorkdirPermissions(
   };
 }
 
+export function parseExternalWorkdirGrantPermissions(
+  value: unknown,
+  label = "External Workdir grant permissions",
+): ExternalWorkdirPermissions {
+  const permissions = parseExternalWorkdirPermissions(value, label);
+  const hierarchical = permissions.read &&
+    (!permissions.command || permissions.write);
+  if (!hierarchical) {
+    throw new Error(
+      `${label} must be READ=(true,false,false), WRITE=(true,true,false), or COMMAND=(true,true,true)`,
+    );
+  }
+  return permissions;
+}
+
 function parseCleanupTarget(value: unknown): WorkingDirectoryCleanupTarget {
   const record = exactRecord(
     value,

web/workspace/src/lib/workspace/api/workers.test.ts

@@ -106,7 +106,7 @@ Deno.test("Worker summary parser preserves attachment-effective External permiss
       source: {
         kind: "external_grant",
         grant_id: "grant-1",
-        grant_permissions: { read: true, write: false, command: true },
+        grant_permissions: { read: true, write: true, command: true },
       },
       materializer_kind: "client_hosted_external",
       status: "active",

web/workspace/src/lib/workspace/console/ConsoleTurnNavigation.browser.spec.ts

@@ -4,15 +4,15 @@ import { cleanup, fireEvent, render } from "@testing-library/svelte";
 import { afterEach, expect, test, vi } from "vitest";
 import ConsoleTurnNavigation from "./ConsoleTurnNavigation.svelte";
 
-const turns = [
-  { id: "u1", user: "First question", assistant: "First answer" },
-  { id: "u2", user: "Second question", assistant: "" },
+const items = [
+  { turnId: "u1", lineId: "u1", user: "First question", assistant: ["First answer"] },
+  { turnId: "u2", lineId: "u2", user: "Second question", assistant: [] },
 ];
 
 afterEach(cleanup);
 
 test("renders one bar per turn and previews both roles on hover", async () => {
-  const view = render(ConsoleTurnNavigation, { turns, onSelect: vi.fn() });
+  const view = render(ConsoleTurnNavigation, { items, onTurnClick: vi.fn() });
   expect(view.getAllByRole("button")).toHaveLength(2);
   expect(view.queryByRole("tooltip")).toBeNull();
   const button = view.getAllByRole("button")[0];
@@ -25,14 +25,14 @@ test("renders one bar per turn and previews both roles on hover", async () => {
   expect(view.queryByRole("tooltip")).toBeNull();
 });
 
-test("focus previews unanswered turns, click selects the user anchor, Escape dismisses", async () => {
-  const onSelect = vi.fn();
-  const view = render(ConsoleTurnNavigation, { turns, onSelect });
+test("focus previews unanswered items, click selects the user anchor, Escape dismisses", async () => {
+  const onTurnClick = vi.fn();
+  const view = render(ConsoleTurnNavigation, { items, onTurnClick });
   const button = view.getAllByRole("button")[1];
   await fireEvent.focus(button);
   expect(view.getByRole("tooltip").textContent).toContain("No response yet");
   await fireEvent.click(button);
-  expect(onSelect).toHaveBeenCalledWith("u2");
+  expect(onTurnClick).toHaveBeenCalledWith(items[1]);
   await fireEvent.keyDown(window, { key: "Escape" });
   expect(view.queryByRole("tooltip")).toBeNull();
   await fireEvent.blur(button);
@@ -43,21 +43,21 @@ test("focus previews unanswered turns, click selects the user anchor, Escape dis
 });
 
 test("updates the visible response in place and removes stale previews on history replacement", async () => {
-  const onSelect = vi.fn();
-  const view = render(ConsoleTurnNavigation, { turns, onSelect });
+  const onTurnClick = vi.fn();
+  const view = render(ConsoleTurnNavigation, { items, onTurnClick });
   await fireEvent.mouseEnter(view.getAllByRole("button")[1]);
-  await view.rerender({ turns: [turns[0], { ...turns[1], assistant: "Streaming answer" }], onSelect });
+  await view.rerender({ items: [items[0], { ...items[1], assistant: ["Streaming answer"] }], onTurnClick });
   expect(view.getByRole("tooltip").textContent).toContain("Streaming answer");
   expect(view.getAllByRole("button")).toHaveLength(2);
-  await view.rerender({ turns: [], onSelect });
+  await view.rerender({ items: [], onTurnClick });
   expect(view.queryByRole("tooltip")).toBeNull();
   expect(view.queryAllByRole("button")).toHaveLength(0);
 });
 
 test("preview content stays text and scrolling the rail dismisses its old position", async () => {
   const view = render(ConsoleTurnNavigation, {
-    turns: [{ id: "u", user: "<img src=x onerror=alert(1)>", assistant: "<script>bad()</script>" }],
-    onSelect: vi.fn(),
+    items: [{ turnId: "u", lineId: "u", user: "<img src=x onerror=alert(1)>", assistant: ["<script>bad()</script>"] }],
+    onTurnClick: vi.fn(),
   });
   await fireEvent.mouseEnter(view.getByRole("button"));
   const tooltip = view.getByRole("tooltip");

web/workspace/src/lib/workspace/console/ConsoleTurnNavigation.svelte

@@ -1,9 +1,20 @@
 <script lang="ts">
-  import type { ConsoleTurn } from './turn-navigation';
+  import type { TurnNavigationItem } from './turn-navigation';
 
-  let { turns, onSelect }: {
-    turns: ConsoleTurn[];
-    onSelect: (id: string) => void;
+  let {
+    items, onTurnClick, hasMore = false, loading = false, error = null,
+    onLoadMore = () => {}, onTopEdgeChange = () => {}, historyAvailable = true,
+    element = $bindable(null),
+  }: {
+    items: TurnNavigationItem[];
+    onTurnClick: (item: TurnNavigationItem) => void;
+    hasMore?: boolean;
+    loading?: boolean;
+    error?: string | null;
+    onLoadMore?: () => void;
+    onTopEdgeChange?: (atTop: boolean) => void;
+    historyAvailable?: boolean;
+    element?: HTMLElement | null;
   } = $props();
 
   const tooltipId = $props.id();
@@ -14,8 +25,8 @@
   let railHeight = $state(0);
   let previewHeight = $state(0);
   let rail: HTMLElement;
-  const preview = $derived(dismissed ? undefined : turns.find(
-    (turn) => turn.id === (hoveredId ?? focusedId),
+  const preview = $derived(dismissed ? undefined : items.find(
+    (turn) => turn.turnId === (hoveredId ?? focusedId),
   ));
   const previewTop = $derived(Math.max(0, Math.min(anchorY, railHeight - previewHeight)));
 
@@ -37,18 +48,35 @@
   bind:clientHeight={railHeight}
   onmouseleave={() => { hoveredId = null; }}
 >
-  <div class="turn-bars" onscroll={() => { dismissed = true; }}>
-    {#each turns as turn, index (turn.id)}
+  <div class="turn-bars turn-list" bind:this={element} onscroll={(event) => {
+    dismissed = true;
+    onTopEdgeChange(event.currentTarget.scrollTop <= 1);
+  }}>
+    <div class="history-boundary">
+      {#if !historyAvailable}
+        <span title="Earlier history is unavailable for this view" aria-label="Earlier history is unavailable for this view">·</span>
+      {:else if loading}
+        <button type="button" disabled aria-label="Loading earlier conversation…">…</button>
+      {:else if error}
+        <button type="button" onclick={onLoadMore} title={error} aria-label="Retry earlier conversation">↻</button>
+      {:else if hasMore}
+        <button type="button" onclick={onLoadMore} title="Earlier conversation available" aria-label="Earlier conversation available">↑</button>
+      {:else}
+        <span title="Start of conversation" aria-label="Start of conversation">·</span>
+      {/if}
+    </div>
+    {#each items as turn, index (turn.turnId)}
       <button
         type="button"
         class="turn-button"
-        class:previewing={preview?.id === turn.id}
+        data-turn-id={turn.turnId}
+        class:previewing={preview?.turnId === turn.turnId}
         aria-label={`Turn ${index + 1}: ${turn.user || 'User message'}`}
-        aria-describedby={preview?.id === turn.id ? tooltipId : undefined}
-        onmouseenter={(event) => show(event, turn.id)}
-        onfocus={(event) => show(event, turn.id)}
+        aria-describedby={preview?.turnId === turn.turnId ? tooltipId : undefined}
+        onmouseenter={(event) => show(event, turn.turnId)}
+        onfocus={(event) => show(event, turn.turnId)}
         onblur={() => { focusedId = null; }}
-        onclick={() => onSelect(turn.id)}
+        onclick={() => onTurnClick(turn)}
       ><span class="turn-bar" aria-hidden="true"></span></button>
     {/each}
   </div>
@@ -60,7 +88,7 @@
     >
       <div class="turn-preview" id={tooltipId} role="tooltip">
         <p class="preview-user">{preview.user || '—'}</p>
-        <p class="preview-assistant">{preview.assistant || 'No response yet'}</p>
+        <p class="preview-assistant">{preview.assistant.join(" ") || 'No response yet'}</p>
       </div>
     </div>
   {/if}
@@ -86,7 +114,19 @@
   .turn-bars::-webkit-scrollbar { display: none; }
 
   /* Center short lists without making overflowing turns unreachable. */
-  .turn-button:first-child { margin-top: auto; }
+  .history-boundary { margin-top: auto; }
+  .history-boundary button, .history-boundary span {
+    display: grid;
+    place-items: center;
+    width: 32px;
+    min-height: 24px;
+    padding: var(--space-1);
+    border: 0;
+    background: transparent;
+    color: var(--text-muted);
+    font: inherit;
+  }
+  .history-boundary button { cursor: pointer; color: var(--tui-cyan); }
   .turn-button:last-child { margin-bottom: auto; }
 
   .turn-button {

web/workspace/src/lib/workspace/console/RichMarkdown.svelte

@@ -20,13 +20,9 @@
 </script>
 
 <script lang="ts">
-  import SvelteMarkdown, {
-    buildUnsupportedHTML,
-    type Renderers,
-    type SvelteMarkdownProps,
-  } from "@humanspeak/svelte-markdown";
+  import type { Renderers } from "@humanspeak/svelte-markdown";
   import { ShikiCode } from "@humanspeak/svelte-markdown/extensions/shiki";
-  import MarkdownLink from "$lib/workspace/console/MarkdownLink.svelte";
+  import SafeMarkdown from "$lib/workspace/markdown/SafeMarkdown.svelte";
 
   type Props = {
     text: string;
@@ -36,24 +32,15 @@
 
   let { text, streamId = "static", class: className = "" }: Props = $props();
 
-  const options = {
-    breaks: true,
-    gfm: true,
-  } satisfies NonNullable<SvelteMarkdownProps["options"]>;
-
   const renderers = {
     code: ShikiCode,
-    html: buildUnsupportedHTML(),
-    link: MarkdownLink,
   } satisfies Partial<Renderers>;
 </script>
 
-<div class={`rich-markdown ${className}`}>
-  <SvelteMarkdown source={text} {streamId} {options} {renderers} streaming />
-</div>
+<SafeMarkdown {text} {streamId} class={`rich-markdown ${className}`} {renderers} streaming />
 
 <style>
-  .rich-markdown {
+  :global(.rich-markdown) {
     color: inherit;
     line-height: var(--line-height-body);
   }

web/workspace/src/lib/workspace/console/history.test.ts

@@ -0,0 +1,388 @@
+import type {
+  SessionConversationTurn,
+  SessionHistoryPage,
+  SessionSnapshotEntry,
+} from "$lib/generated/protocol";
+import {
+  applyConsoleHistoryPage,
+  beginConsoleHistoryRequest,
+  type ConsoleHistoryState,
+  conversationTurnPreviews,
+  conversationTurnPreviewsFromLines,
+  emptyConsoleHistoryState,
+  historyEntries,
+  setConsoleHistoryTopEdge,
+  shouldLoadHistoryAtTop,
+} from "./history";
+
+declare const Deno: { test(name: string, fn: () => void): void };
+
+function assert(condition: boolean, message: string): void {
+  if (!condition) throw new Error(message);
+}
+
+function message(
+  id: string,
+  role: "user" | "assistant",
+  text: string,
+): SessionSnapshotEntry {
+  return {
+    entry_id: id,
+    timestamp: 1,
+    provenance: role === "user" ? "human_input" : "model_output",
+    kind: "message",
+    role,
+    content: [{ kind: "text", text }],
+  };
+}
+
+function turn(index: number): SessionConversationTurn {
+  return {
+    turn_id: `u-${index}`,
+    entries: [
+      message(`u-${index}`, "user", `question ${index}\nignored`),
+      message(`a-progress-${index}`, "assistant", `working ${index}`),
+      message(
+        `a-final-${index}`,
+        "assistant",
+        `done ${index}\ndetail a\ndetail b\ndetail c`,
+      ),
+    ],
+  };
+}
+
+function page(
+  turns: SessionConversationTurn[],
+  cursor: string | null,
+  lineageId = "lineage-a",
+  compactAncestorLineageIds: string[] = [],
+  parentLineage?: {
+    lineage_id: string;
+    adopted_through_turn?: SessionConversationTurn | null;
+  },
+): SessionHistoryPage {
+  return {
+    session_id: "session-a",
+    lineage_id: lineageId,
+    compact_ancestor_lineage_ids: compactAncestorLineageIds,
+    parent_lineage: parentLineage,
+    turns,
+    next_cursor: cursor,
+    has_more: cursor !== null,
+  };
+}
+
+Deno.test("history prepends 12 turns as 5 then 5 then 2 without duplicates", () => {
+  let state = emptyConsoleHistoryState();
+  state = beginConsoleHistoryRequest(state, null)!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([8, 9, 10, 11, 12].map(turn), "cursor-8"),
+    null,
+  );
+  state = beginConsoleHistoryRequest(state, "cursor-8")!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([3, 4, 5, 6, 7].map(turn), "cursor-3"),
+    "cursor-8",
+  );
+  state = beginConsoleHistoryRequest(state, "cursor-3")!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([1, 2].map(turn), null),
+    "cursor-3",
+  );
+  assert(state.turns.length === 12, "all real turns must be retained");
+  assert(state.turns[0].turn_id === "u-1", "pages must remain chronological");
+  assert(
+    !state.hasMore && state.cursor === null,
+    "final short page must end history",
+  );
+
+  state = { ...state, requestedCursor: "__initial__", status: "loading" };
+  state = applyConsoleHistoryPage(
+    state,
+    page([8, 9, 10, 11, 12].map(turn), "cursor-8"),
+    null,
+  );
+  assert(
+    state.turns.length === 12,
+    "refresh must dedupe stable turn identities",
+  );
+  assert(
+    historyEntries(state).length === 36,
+    "entries must dedupe by stable identity",
+  );
+});
+
+Deno.test("refresh replaces overlapping latest turns while retaining loaded earlier turns", () => {
+  let state = emptyConsoleHistoryState();
+  state = beginConsoleHistoryRequest(state, null)!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([8, 9, 10, 11, 12].map(turn), "cursor-8"),
+    null,
+  );
+  state = beginConsoleHistoryRequest(state, "cursor-8")!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([3, 4, 5, 6, 7].map(turn), "cursor-3"),
+    "cursor-8",
+  );
+
+  const updated = turn(12);
+  updated.entries.push(message("a-later-12", "assistant", "actually finished"));
+  state = beginConsoleHistoryRequest(state, null)!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([8, 9, 10, 11].map(turn).concat(updated), "stale-cursor-is-ignored"),
+    null,
+  );
+
+  assert(
+    state.turns.length === 10,
+    "refresh must not discard loaded earlier turns",
+  );
+  assert(
+    state.turns.at(-1)?.entries.at(-1)?.entry_id === "a-later-12",
+    "refresh must replace an overlapping turn with its latest committed entries",
+  );
+  assert(
+    state.cursor === "cursor-3",
+    "refresh must retain the oldest paging boundary",
+  );
+});
+
+Deno.test("same-lineage refresh without overlap replaces the paging boundary", () => {
+  let state: ConsoleHistoryState = {
+    ...emptyConsoleHistoryState(),
+    sessionId: "session-a",
+    lineageId: "lineage-a",
+    turns: [1, 2, 3, 4].map(turn),
+    cursor: null,
+    hasMore: false,
+    status: "loading",
+    requestedCursor: "__initial__",
+  };
+  state = applyConsoleHistoryPage(
+    state,
+    page([6, 7, 8, 9, 10].map(turn), "cursor-6", "lineage-a"),
+    null,
+  );
+
+  assert(
+    state.turns.map((value) => value.turn_id).join(",") ===
+      "u-1,u-2,u-3,u-4,u-6,u-7,u-8,u-9,u-10",
+    "a reconnect may preserve loaded rows while still exposing the missing gap",
+  );
+  assert(
+    state.cursor === "cursor-6" && state.hasMore,
+    "a non-overlapping same-lineage page must replace an exhausted old boundary",
+  );
+});
+
+Deno.test("changed lineage keeps the adopted prefix and discards the replaced branch", () => {
+  let state = emptyConsoleHistoryState();
+  state = beginConsoleHistoryRequest(state, null)!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([6, 7, 8, 9, 10].map(turn), "cursor-6"),
+    null,
+  );
+  state = beginConsoleHistoryRequest(state, "cursor-6")!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([1, 2, 3, 4, 5].map(turn), null),
+    "cursor-6",
+  );
+
+  state = beginConsoleHistoryRequest(state, null)!;
+  state = applyConsoleHistoryPage(
+    state,
+    page([3, 4, 5, 11, 12].map(turn), "cursor-3-new", "lineage-b"),
+    null,
+  );
+
+  assert(
+    state.turns.map((value) => value.turn_id).join(",") ===
+      "u-1,u-2,u-3,u-4,u-5,u-11,u-12",
+    "rewind must preserve only the prefix adopted by the new lineage",
+  );
+  assert(
+    state.cursor === "cursor-3-new" && state.hasMore,
+    "a changed lineage must replace the stale paging cursor",
+  );
+});
+
+Deno.test("Compact lineage refresh preserves already loaded adopted history", () => {
+  let state: ConsoleHistoryState = {
+    ...emptyConsoleHistoryState(),
+    sessionId: "session-a",
+    lineageId: "lineage-a",
+    turns: Array.from({ length: 10 }, (_, index) => turn(index + 1)),
+    status: "loading",
+    requestedCursor: "__initial__",
+  };
+  state = applyConsoleHistoryPage(
+    state,
+    page(
+      [11, 12, 13, 14, 15].map(turn),
+      "cursor-11-new",
+      "lineage-compact",
+      ["lineage-a"],
+    ),
+    null,
+  );
+
+  assert(
+    state.turns.map((value) => value.turn_id).join(",") ===
+      Array.from({ length: 15 }, (_, index) => `u-${index + 1}`).join(","),
+    "Compact must keep the adopted prefix without requiring newest-page overlap",
+  );
+  assert(
+    state.cursor === "cursor-11-new" && state.hasMore,
+    "Compact must replace the old-lineage cursor even when adopted turns are preserved",
+  );
+});
+
+Deno.test("fork lineage boundary preserves an adopted prefix without page overlap", () => {
+  let state: ConsoleHistoryState = {
+    ...emptyConsoleHistoryState(),
+    sessionId: "session-a",
+    lineageId: "lineage-a",
+    turns: Array.from({ length: 50 }, (_, index) => turn(index + 1)),
+    cursor: null,
+    hasMore: false,
+    status: "loading",
+    requestedCursor: "__initial__",
+  };
+  state.turns[24]!.entries.push(
+    message("a-unadopted-25", "assistant", "stale sibling response"),
+  );
+  const adoptedBoundary = turn(25);
+  state = applyConsoleHistoryPage(
+    state,
+    page(
+      [101, 102, 103, 104, 105].map(turn),
+      "cursor-101",
+      "lineage-fork",
+      [],
+      {
+        lineage_id: "lineage-a",
+        adopted_through_turn: adoptedBoundary,
+      },
+    ),
+    null,
+  );
+
+  assert(
+    state.turns.map((value) => value.turn_id).join(",") ===
+      [
+        ...Array.from({ length: 25 }, (_, index) => `u-${index + 1}`),
+        ...Array.from({ length: 5 }, (_, index) => `u-${index + 101}`),
+      ].join(","),
+    "fork refresh must retain only the authoritative adopted prefix",
+  );
+  assert(
+    historyEntries(state).every((entry) => entry.entry_id !== "a-unadopted-25"),
+    "the canonical provider boundary must trim a sibling entry in the same visible turn",
+  );
+  assert(
+    state.cursor === "cursor-101" && state.hasMore,
+    "fork refresh must replace the old paging boundary",
+  );
+});
+
+Deno.test("changed lineage without a stable overlap replaces retained turns", () => {
+  let state: ConsoleHistoryState = {
+    ...emptyConsoleHistoryState(),
+    sessionId: "session-a",
+    lineageId: "lineage-a",
+    turns: [1, 2, 3].map(turn),
+    cursor: "old-cursor",
+    hasMore: true,
+    status: "loading",
+    requestedCursor: "__initial__",
+  };
+  state = applyConsoleHistoryPage(
+    state,
+    page([11, 12].map(turn), null, "lineage-b"),
+    null,
+  );
+  assert(
+    state.turns.map((value) => value.turn_id).join(",") === "u-11,u-12",
+    "unrelated lineage content must not survive refresh",
+  );
+  assert(
+    state.cursor === null && !state.hasMore,
+    "new lineage boundary must be authoritative",
+  );
+});
+
+Deno.test("line previews include a current turn outside the retained five-turn page", () => {
+  const lines = [1, 2, 3, 4, 5, 6].flatMap((index) => [
+    {
+      id: `user-${index}`,
+      entryId: `u-${index}`,
+      kind: "user" as const,
+      title: "User",
+      body: `question ${index}`,
+      source: "event" as const,
+    },
+    {
+      id: `assistant-${index}`,
+      entryId: `a-${index}`,
+      kind: "assistant" as const,
+      title: "Assistant",
+      body: `done ${index}`,
+      source: "event" as const,
+    },
+  ]);
+  assert(
+    conversationTurnPreviewsFromLines(lines).map((preview) => preview.turnId)
+      .join(",") ===
+      "u-1,u-2,u-3,u-4,u-5,u-6",
+    "turn navigation must include unmatched current snapshot turns in transcript order",
+  );
+});
+
+Deno.test("turn preview uses one user line and final non-empty assistant up to three lines", () => {
+  const preview = conversationTurnPreviews([turn(4)])[0];
+  assert(preview.user === "question 4", "user preview must use its first line");
+  assert(
+    preview.assistant.join("|") === "done 4|detail a|detail b",
+    "preview must choose the final assistant and cap it at three lines",
+  );
+});
+
+Deno.test("top sentinel requests only once until it leaves the edge", () => {
+  let state: ConsoleHistoryState = {
+    ...emptyConsoleHistoryState(),
+    status: "ready",
+    cursor: "older",
+    hasMore: true,
+  };
+  assert(
+    shouldLoadHistoryAtTop(state, true),
+    "armed top edge should request a page",
+  );
+  state = beginConsoleHistoryRequest(state, "older")!;
+  assert(
+    !shouldLoadHistoryAtTop(state, true),
+    "in-flight page must suppress duplicates",
+  );
+  state = {
+    ...state,
+    status: "ready",
+    requestedCursor: null,
+  };
+  assert(
+    !shouldLoadHistoryAtTop(state, true),
+    "stationary sentinel must not drain history",
+  );
+  state = setConsoleHistoryTopEdge(state, false);
+  assert(
+    shouldLoadHistoryAtTop(state, true),
+    "leaving the top must rearm one request",
+  );
+});

web/workspace/src/lib/workspace/console/history.ts

@@ -0,0 +1,338 @@
+import type { ConsoleLine } from "./model.ts";
+import type {
+  SessionConversationTurn,
+  SessionHistoryPage,
+  SessionSnapshotEntry,
+} from "$lib/generated/protocol";
+
+export const CONSOLE_HISTORY_PAGE_TURNS = 5;
+
+export type ConsoleHistoryStatus = "idle" | "loading" | "ready" | "error";
+
+export type ConsoleHistoryState = {
+  sessionId: string | null;
+  lineageId: string | null;
+  turns: SessionConversationTurn[];
+  cursor: string | null;
+  hasMore: boolean;
+  status: ConsoleHistoryStatus;
+  error: string | null;
+  /** Cursor currently in flight; prevents duplicate sentinel requests. */
+  requestedCursor: string | null;
+  /** Rearmed only after leaving the top edge or an explicit user action. */
+  topEdgeArmed: boolean;
+};
+
+export type ConsoleTurnPreview = {
+  turnId: string;
+  lineId: string;
+  user: string;
+  assistant: string[];
+};
+
+export function emptyConsoleHistoryState(): ConsoleHistoryState {
+  return {
+    sessionId: null,
+    lineageId: null,
+    turns: [],
+    cursor: null,
+    hasMore: false,
+    status: "idle",
+    error: null,
+    requestedCursor: null,
+    topEdgeArmed: true,
+  };
+}
+
+export function beginConsoleHistoryRequest(
+  state: ConsoleHistoryState,
+  cursor: string | null,
+): ConsoleHistoryState | null {
+  if (state.status === "loading" || state.requestedCursor !== null) return null;
+  if (cursor !== null && (!state.hasMore || cursor !== state.cursor)) {
+    return null;
+  }
+  return {
+    ...state,
+    status: "loading",
+    error: null,
+    requestedCursor: cursor ?? "__initial__",
+    topEdgeArmed: cursor === null ? state.topEdgeArmed : false,
+  };
+}
+
+export function applyConsoleHistoryPage(
+  state: ConsoleHistoryState,
+  page: SessionHistoryPage,
+  requestedCursor: string | null,
+): ConsoleHistoryState {
+  const requestKey = requestedCursor ?? "__initial__";
+  if (state.requestedCursor !== requestKey) return state;
+
+  const initial = requestedCursor === null;
+  if (
+    !initial &&
+    (state.sessionId !== page.session_id || state.lineageId !== page.lineage_id)
+  ) {
+    return failConsoleHistoryRequest(
+      state,
+      "The conversation changed while earlier history was loading. Retry from the current view.",
+    );
+  }
+
+  const incoming = page.turns.filter((turn) => turn.entries.length > 0);
+  const refreshingSameSession = initial &&
+    state.sessionId === page.session_id &&
+    state.turns.length > 0;
+  const refreshingSameLineage = refreshingSameSession &&
+    state.lineageId === page.lineage_id;
+  const refreshingParentLineage = refreshingSameSession &&
+    state.lineageId !== null &&
+    page.parent_lineage?.lineage_id === state.lineageId;
+  const refreshingCompactDescendant = refreshingSameSession &&
+    state.lineageId !== null &&
+    (page.compact_ancestor_lineage_ids ?? []).includes(state.lineageId);
+  const refreshBridgesRetained = refreshingSameLineage && incoming.some(
+    (turn) => state.turns.some((retained) => retained.turn_id === turn.turn_id),
+  );
+  const turns = initial
+    ? refreshingSameLineage
+      ? mergeRefreshedTurns(state.turns, incoming)
+      : refreshingParentLineage
+      ? reconcileParentLineage(
+        state.turns,
+        incoming,
+        page.parent_lineage?.adopted_through_turn ?? null,
+      )
+      : refreshingCompactDescendant
+      ? mergeRefreshedTurns(state.turns, incoming)
+      : refreshingSameSession
+      ? reconcileChangedLineage(state.turns, incoming)
+      : dedupeTurns(incoming)
+    : dedupeTurns([...incoming, ...state.turns]);
+  return {
+    ...state,
+    sessionId: page.session_id,
+    lineageId: page.lineage_id,
+    turns,
+    cursor: refreshBridgesRetained ? state.cursor : (page.next_cursor ?? null),
+    hasMore: refreshBridgesRetained ? state.hasMore : page.has_more,
+    status: "ready",
+    error: null,
+    requestedCursor: null,
+  };
+}
+
+export function failConsoleHistoryRequest(
+  state: ConsoleHistoryState,
+  message: string,
+): ConsoleHistoryState {
+  return {
+    ...state,
+    status: "error",
+    error: message.slice(0, 512),
+    requestedCursor: null,
+  };
+}
+
+export function setConsoleHistoryTopEdge(
+  state: ConsoleHistoryState,
+  atTop: boolean,
+): ConsoleHistoryState {
+  if (!atTop && !state.topEdgeArmed) return { ...state, topEdgeArmed: true };
+  return state;
+}
+
+export function shouldLoadHistoryAtTop(
+  state: ConsoleHistoryState,
+  atTop: boolean,
+): boolean {
+  return atTop && state.topEdgeArmed && state.hasMore &&
+    state.status !== "loading" && state.requestedCursor === null;
+}
+
+export function historyEntries(
+  state: ConsoleHistoryState,
+): SessionSnapshotEntry[] {
+  return state.turns.flatMap((turn) => turn.entries);
+}
+
+export function conversationTurnPreviews(
+  turns: readonly SessionConversationTurn[],
+): ConsoleTurnPreview[] {
+  return turns.map((turn) => {
+    const userEntry = turn.entries.find(isUserEntry);
+    const assistants = turn.entries
+      .filter(isAssistantEntry)
+      .map(entryText)
+      .filter((text) => text.trim().length > 0);
+    return {
+      turnId: turn.turn_id,
+      lineId: userEntry?.entry_id ?? turn.turn_id,
+      user: firstNonEmptyLine(userEntry ? entryText(userEntry) : ""),
+      assistant: previewAssistant(assistants.at(-1) ?? ""),
+    };
+  });
+}
+
+export function conversationTurnPreviewsFromLines(
+  lines: readonly ConsoleLine[],
+): ConsoleTurnPreview[] {
+  const previews: ConsoleTurnPreview[] = [];
+  let current: {
+    turnId: string;
+    lineId: string;
+    user: string;
+    assistants: string[];
+  } | null = null;
+  for (const line of lines) {
+    if (line.kind === "user") {
+      if (current) {
+        previews.push({
+          turnId: current.turnId,
+          lineId: current.lineId,
+          user: current.user,
+          assistant: previewAssistant(current.assistants.at(-1) ?? ""),
+        });
+      }
+      const stableId = line.entryId ?? line.id;
+      current = {
+        turnId: stableId,
+        lineId: stableId,
+        user: firstNonEmptyLine(line.body),
+        assistants: [],
+      };
+    } else if (
+      (line.kind === "assistant" ||
+        (line.kind === "in_flight" && line.title === "in-flight assistant text")) &&
+      current && line.body.trim().length > 0
+    ) {
+      current.assistants.push(line.body);
+    }
+  }
+  if (current) {
+    previews.push({
+      turnId: current.turnId,
+      lineId: current.lineId,
+      user: current.user,
+      assistant: previewAssistant(current.assistants.at(-1) ?? ""),
+    });
+  }
+  return previews;
+}
+
+function previewAssistant(value: string): string[] {
+  return value
+    .split(/\r?\n/)
+    .map((line) => line.trim())
+    .filter(Boolean)
+    .slice(0, 3);
+}
+
+function reconcileParentLineage(
+  retained: readonly SessionConversationTurn[],
+  refreshed: readonly SessionConversationTurn[],
+  adoptedThroughTurn: SessionConversationTurn | null,
+): SessionConversationTurn[] {
+  if (adoptedThroughTurn === null) return dedupeTurns(refreshed);
+  const boundary = retained.findIndex((turn) =>
+    turn.turn_id === adoptedThroughTurn.turn_id
+  );
+  if (boundary < 0) return dedupeTurns(refreshed);
+  const refreshedIncludesBoundary = refreshed.some((turn) =>
+    turn.turn_id === adoptedThroughTurn.turn_id
+  );
+  return dedupeTurns([
+    ...retained.slice(0, boundary),
+    ...(refreshedIncludesBoundary ? [] : [adoptedThroughTurn]),
+    ...refreshed,
+  ]);
+}
+
+function reconcileChangedLineage(
+  retained: readonly SessionConversationTurn[],
+  refreshed: readonly SessionConversationTurn[],
+): SessionConversationTurn[] {
+  const retainedPositions = new Map(
+    retained.map((turn, index) => [turn.turn_id, index] as const),
+  );
+  const firstShared = refreshed.find((turn) =>
+    retainedPositions.has(turn.turn_id)
+  );
+  if (!firstShared) return dedupeTurns(refreshed);
+
+  const retainedPrefix = retained.slice(
+    0,
+    retainedPositions.get(firstShared.turn_id) ?? 0,
+  );
+  return dedupeTurns([...retainedPrefix, ...refreshed]);
+}
+
+function mergeRefreshedTurns(
+  retained: readonly SessionConversationTurn[],
+  refreshed: readonly SessionConversationTurn[],
+): SessionConversationTurn[] {
+  const refreshedIds = new Set(refreshed.map((turn) => turn.turn_id));
+  return dedupeTurns([
+    ...retained.filter((turn) => !refreshedIds.has(turn.turn_id)),
+    ...refreshed,
+  ]);
+}
+
+function dedupeTurns(
+  turns: readonly SessionConversationTurn[],
+): SessionConversationTurn[] {
+  const seenTurns = new Set<string>();
+  const seenEntries = new Set<string>();
+  const result: SessionConversationTurn[] = [];
+  for (const turn of turns) {
+    if (seenTurns.has(turn.turn_id)) continue;
+    const entries = turn.entries.filter((entry) => {
+      if (seenEntries.has(entry.entry_id)) return false;
+      seenEntries.add(entry.entry_id);
+      return true;
+    });
+    if (entries.length === 0) continue;
+    seenTurns.add(turn.turn_id);
+    result.push({ ...turn, entries });
+  }
+  return result;
+}
+
+function isUserEntry(entry: SessionSnapshotEntry): boolean {
+  return entry.kind === "user_input" ||
+    (entry.kind === "message" && entry.role === "user");
+}
+
+function isAssistantEntry(entry: SessionSnapshotEntry): boolean {
+  return entry.kind === "message" && entry.role === "assistant";
+}
+
+function entryText(entry: SessionSnapshotEntry): string {
+  switch (entry.kind) {
+    case "user_input":
+      return entry.segments.map((segment) => {
+        if (segment.kind === "text" || segment.kind === "paste") {
+          return segment.content;
+        }
+        if (segment.kind === "file_ref") return `@file ${segment.path}`;
+        if (segment.kind === "uploaded_file") {
+          return `[Attachment: ${segment.file.file_name}]`;
+        }
+        if (segment.kind === "paste_artifact") {
+          return `[Large paste ${segment.artifact.artifact_id}]`;
+        }
+        return "";
+      }).filter(Boolean).join("\n");
+    case "message":
+      return entry.content.map((part) =>
+        part.kind === "text" ? part.text : part.refusal
+      ).join("\n");
+    default:
+      return "";
+  }
+}
+
+function firstNonEmptyLine(value: string): string {
+  return value.split(/\r?\n/).map((line) => line.trim()).find(Boolean) ?? "—";
+}

web/workspace/src/lib/workspace/console/model.test.ts

@@ -9,6 +9,7 @@ import {
   consoleWorkerViews,
   createConsoleProjector,
   isConsoleProjectionEvent,
+  mergeCommittedHistoryLines,
   projectConsole,
   projectConsoleLines,
   projectOverviewLines,
@@ -2950,3 +2951,203 @@ Deno.test("new invoke resets stats before the next RunEnd", () => {
 
   assertEquals(projection.lines.at(-1)?.body, "0s ・0 reqs ↑0/↓0");
 });
+
+Deno.test("committed assistant identity reconciles the live block without text matching", () => {
+  const lines = projectConsole([
+    {
+      eventId: "user-live",
+      event: {
+        event: "user_message",
+        data: {
+          entry_id: "user-entry",
+          segments: [{ kind: "text", content: "question" }],
+        },
+      },
+    },
+    {
+      eventId: "assistant-live",
+      event: { event: "text_done", data: { text: "final answer" } },
+    },
+    {
+      eventId: "assistant-commit",
+      event: {
+        event: "session_entry_committed",
+        data: {
+          entry: {
+            entry_id: "assistant-entry",
+            timestamp: 7,
+            provenance: "model_output",
+            kind: "message",
+            role: "assistant",
+            content: [{ kind: "text", text: "final answer" }],
+          },
+        },
+      },
+    },
+  ]).lines;
+  assertEquals(lines.filter((line) => line.kind === "assistant").length, 1);
+  assertEquals(
+    lines.find((line) => line.kind === "assistant")?.entryId,
+    "assistant-entry",
+  );
+  assertEquals(
+    lines.find((line) => line.kind === "user")?.entryId,
+    "user-entry",
+  );
+});
+
+Deno.test("committed tool identities reconcile one live call block", () => {
+  const lines = projectConsole([
+    {
+      eventId: "tool-live",
+      event: {
+        event: "tool_call_done",
+        data: { id: "call-1", name: "Read", arguments: '{"file_path":"a"}' },
+      },
+    },
+    {
+      eventId: "tool-call-commit",
+      event: {
+        event: "session_entry_committed",
+        data: {
+          entry: {
+            entry_id: "tool-call-entry",
+            timestamp: 8,
+            provenance: "model_output",
+            kind: "tool_call",
+            call_id: "call-1",
+            name: "Read",
+            arguments: '{"file_path":"a"}',
+          },
+        },
+      },
+    },
+    {
+      eventId: "tool-result-live",
+      event: {
+        event: "tool_result",
+        data: {
+          id: "call-1",
+          summary: "read",
+          output: "contents",
+          is_error: false,
+        },
+      },
+    },
+    {
+      eventId: "tool-result-commit",
+      event: {
+        event: "session_entry_committed",
+        data: {
+          entry: {
+            entry_id: "tool-result-entry",
+            timestamp: 9,
+            provenance: "tool_output",
+            kind: "tool_result",
+            call_id: "call-1",
+            summary: "read",
+            content: "contents",
+            is_error: false,
+          },
+        },
+      },
+    },
+  ]).lines;
+
+  assertEquals(
+    lines.filter((line) => line.toolCall?.id === "call-1").length,
+    1,
+  );
+  assertEquals(lines[0].entryId, "tool-result-entry");
+  assertEquals(lines[0].toolCall?.state, "done");
+});
+
+Deno.test("committed history preserves unmatched current rows in stable entry order", () => {
+  const history = [2, 3, 4, 5, 6].flatMap((turn) => {
+    const user = consoleLine(`history-user-${turn}`, "user");
+    user.entryId = `user-${turn}`;
+    const assistant = consoleLine(`history-assistant-${turn}`, "assistant");
+    assistant.entryId = `assistant-${turn}`;
+    return [user, assistant];
+  });
+  const current = [1, 2, 3, 4, 5, 6].flatMap((turn) => {
+    const user = consoleLine(`current-user-${turn}`, "user");
+    user.entryId = `user-${turn}`;
+    const assistant = consoleLine(`current-assistant-${turn}`, "assistant");
+    assistant.entryId = `assistant-${turn}`;
+    return [user, assistant];
+  });
+
+  const merged = mergeCommittedHistoryLines(history, current);
+  assertEquals(
+    merged.map((line) => line.entryId),
+    [1, 2, 3, 4, 5, 6].flatMap((turn) => [
+      `user-${turn}`,
+      `assistant-${turn}`,
+    ]),
+  );
+  assert(
+    merged.every((line) => line.id.startsWith("current-")),
+    "the ordered current snapshot must remain authoritative for overlapping entries",
+  );
+});
+
+Deno.test("committed history places omitted retained rows between snapshot anchors", () => {
+  const makeLine = (prefix: string, turn: number) => {
+    const line = consoleLine(`${prefix}-${turn}`, "user");
+    line.entryId = `user-${turn}`;
+    return line;
+  };
+  const history = [2, 3, 4, 5, 6].map((turn) => makeLine("history", turn));
+  const current = [1, 2, 6].map((turn) => makeLine("current", turn));
+
+  assertEquals(
+    mergeCommittedHistoryLines(history, current).map((line) => line.entryId),
+    [1, 2, 3, 4, 5, 6].map((turn) => `user-${turn}`),
+  );
+});
+
+Deno.test("committed history places current context before an interior first anchor", () => {
+  const makeLine = (prefix: string, turn: number) => {
+    const line = consoleLine(`${prefix}-${turn}`, "user");
+    line.entryId = `user-${turn}`;
+    return line;
+  };
+  const history = [6, 7, 8, 9, 10].map((turn) => makeLine("history", turn));
+  const current = [1, 8, 10].map((turn) => makeLine("current", turn));
+
+  assertEquals(
+    mergeCommittedHistoryLines(history, current).map((line) => line.entryId),
+    [1, 6, 7, 8, 9, 10].map((turn) => `user-${turn}`),
+  );
+});
+
+Deno.test("committed history places a retained suffix before newer current-only rows", () => {
+  const makeLine = (prefix: string, turn: number) => {
+    const line = consoleLine(`${prefix}-${turn}`, "user");
+    line.entryId = `user-${turn}`;
+    return line;
+  };
+  const history = [2, 3, 4, 5, 6].map((turn) => makeLine("history", turn));
+  const current = [1, 2, 7].map((turn) => makeLine("current", turn));
+
+  assertEquals(
+    mergeCommittedHistoryLines(history, current).map((line) => line.entryId),
+    [1, 2, 3, 4, 5, 6, 7].map((turn) => `user-${turn}`),
+  );
+});
+
+Deno.test("committed history inserts current live rows after their last stable anchor", () => {
+  const historyUser = consoleLine("history-user", "user");
+  historyUser.entryId = "user-1";
+  const currentUser = consoleLine("current-user", "user");
+  currentUser.entryId = "user-1";
+  const live = consoleLine("live-assistant", "in_flight");
+
+  assertEquals(
+    mergeCommittedHistoryLines([historyUser], [currentUser, live]).map((line) =>
+      line.id
+    ),
+    ["current-user", "live-assistant"],
+  );
+});

web/workspace/src/lib/workspace/console/model.ts

@@ -10,6 +10,7 @@ import type {
   InternalWorkerRef,
   InternalWorkerSnapshot,
   Segment,
+  SessionSnapshotEntry,
   WorkerState,
   WorkerStateSnapshot,
   WorkerStatus,
@@ -90,6 +91,8 @@ export type ConsoleLine = {
   compaction?: ConsoleCompaction;
   diff?: ConsoleDiffLine[];
   eventId?: string | null;
+  /** Stable durable identity when this line originates from a committed entry. */
+  entryId?: string;
   source: "event";
   streaming?: boolean;
   error?: boolean;
@@ -246,6 +249,86 @@ export function createConsoleProjector() {
   };
 }
 
+export function mergeCommittedHistoryLines(
+  history: ConsoleLine[],
+  current: ConsoleLine[],
+): ConsoleLine[] {
+  const currentEntryIds = new Set(
+    current.map((line) => line.entryId).filter((id): id is string =>
+      Boolean(id)
+    ),
+  );
+  const historyPositions = new Map<string, number>();
+  history.forEach((line, index) => {
+    if (line.entryId && !historyPositions.has(line.entryId)) {
+      historyPositions.set(line.entryId, index);
+    }
+  });
+
+  // Use stable entries that occur in the same order in both projections as
+  // anchors. History-only rows are inserted in their retained interval, while
+  // current-only rows retain the snapshot's authoritative order. This handles
+  // Compact snapshots that preserve only a non-contiguous subset of context.
+  const anchors: Array<{ history: number; current: number }> = [];
+  let lastHistoryIndex = -1;
+  current.forEach((line, currentIndex) => {
+    const historyIndex = line.entryId
+      ? historyPositions.get(line.entryId)
+      : undefined;
+    if (historyIndex !== undefined && historyIndex > lastHistoryIndex) {
+      anchors.push({ history: historyIndex, current: currentIndex });
+      lastHistoryIndex = historyIndex;
+    }
+  });
+
+  if (anchors.length === 0) {
+    return [
+      ...history.filter((line) =>
+        !line.entryId || !currentEntryIds.has(line.entryId)
+      ),
+      ...current,
+    ];
+  }
+
+  const merged: ConsoleLine[] = [];
+  let historyCursor = 0;
+  let currentCursor = 0;
+  const appendHistoryInterval = (end: number) => {
+    for (; historyCursor < end; historyCursor += 1) {
+      const line = history[historyCursor]!;
+      if (!line.entryId || !currentEntryIds.has(line.entryId)) {
+        merged.push(line);
+      }
+    }
+  };
+  for (const [index, anchor] of anchors.entries()) {
+    if (index === 0) {
+      // Current rows before the first shared entry can be older retained
+      // context that the newest history page starts after.
+      merged.push(...current.slice(currentCursor, anchor.current));
+      appendHistoryInterval(anchor.history);
+    } else {
+      appendHistoryInterval(anchor.history);
+      merged.push(...current.slice(currentCursor, anchor.current));
+    }
+    merged.push(current[anchor.current]!);
+    historyCursor = anchor.history + 1;
+    currentCursor = anchor.current + 1;
+  }
+  appendHistoryInterval(history.length);
+  merged.push(...current.slice(currentCursor));
+  return merged;
+}
+
+export function projectSessionHistoryEntries(
+  entries: SessionSnapshotEntry[],
+  cwd: string | null,
+): ConsoleLine[] {
+  return projectVisibleConsole(
+    snapshotProjectionFromSession("history", { entries }, cwd),
+  ).lines;
+}
+
 function projectVisibleConsole(
   projection: ConsoleProjection,
 ): ConsoleProjection {
@@ -813,14 +896,19 @@ export function applyProtocolEvent(
 
   switch (event.event) {
     case "user_message":
-      next.lines.push(
-        line(
+      next.lines.push({
+        ...line(
           envelope.eventId,
           "user",
           "User",
           segmentsToText(event.data.segments),
         ),
-      );
+        entryId: event.data.entry_id ?? undefined,
+      });
+      break;
+    case "session_entry_committed":
+      reconcileCommittedSessionEntry(next, event.data.entry);
+      applySessionEntry(next, envelope.eventId, event.data.entry);
       break;
     case "system_item":
       next.lines.push(systemItemLine(envelope.eventId, event.data.item));
@@ -1507,6 +1595,7 @@ function readAggregateLine(group: ConsoleLine[]): ConsoleLine {
     toolStatus: hasError ? "failed" : inProgress ? "reading…" : "done",
     detail: calls.map(readDetail).join("\n\n"),
     eventId: group.at(-1)?.eventId,
+    entryId: group.at(-1)?.entryId,
     source: "event",
     streaming: inProgress,
     error: hasError,
@@ -1971,6 +2060,22 @@ function snapshotProjectionFromSession(
   return projection;
 }
 
+function reconcileCommittedSessionEntry(
+  projection: ConsoleProjection,
+  entry: SessionSnapshotEntry,
+): void {
+  if (entry.kind !== "message" || entry.role !== "assistant") return;
+  for (let index = projection.lines.length - 1; index >= 0; index -= 1) {
+    const line = projection.lines[index];
+    if (line.entryId) continue;
+    if (line.kind === "assistant" || line.kind === "in_flight") {
+      projection.lines.splice(index, 1);
+      return;
+    }
+    if (line.kind === "user") return;
+  }
+}
+
 function applySessionEntry(
   projection: ConsoleProjection,
   fallbackEventId: string,
@@ -1978,6 +2083,7 @@ function applySessionEntry(
 ): void {
   if (!isRecord(value)) return;
   const eventId = stringField(value, "entry_id") ?? fallbackEventId;
+  const lineCountBefore = projection.lines.length;
   switch (stringField(value, "kind")) {
     case "user_input":
       projection.lines.push(
@@ -2035,6 +2141,18 @@ function applySessionEntry(
     default:
       break;
   }
+  const entryId = stringField(value, "entry_id");
+  if (entryId) {
+    for (
+      let index = Math.max(0, lineCountBefore - 1);
+      index < projection.lines.length;
+      index += 1
+    ) {
+      if (projection.lines[index].eventId === eventId) {
+        projection.lines[index].entryId = entryId;
+      }
+    }
+  }
 }
 
 function applyLoggedUserInput(

web/workspace/src/lib/workspace/console/turn-navigation.ts

@@ -34,3 +34,14 @@ export function consoleTurns(lines: readonly ConsoleLine[]): ConsoleTurn[] {
   }
   return turns;
 }
+
+import type { SessionConversationTurn } from "$lib/generated/protocol";
+import { type ConsoleTurnPreview, conversationTurnPreviews } from "./history";
+
+export type TurnNavigationItem = ConsoleTurnPreview;
+
+export function buildTurnNavigationItems(
+  turns: readonly SessionConversationTurn[],
+): TurnNavigationItem[] {
+  return conversationTurnPreviews(turns);
+}

web/workspace/src/lib/workspace/console/worker-console.ui.test.ts

@@ -496,11 +496,13 @@ Deno.test("workspace Memory surfaces use read-only scoped memory APIs", async ()
   assert(
     memoryDocumentLoad.includes("workspaceApiPath(params.workspaceId") &&
       memoryDocumentLoad.includes('"/memory"') &&
-      memoryDocumentPage.includes("Memory Document") &&
-      memoryDocumentPage.includes("This view is read-only") &&
+      memoryDocumentPage.includes("DocumentMarkdown from") &&
+      memoryDocumentPage.includes("Read-only") &&
       memoryDocumentPage.includes("data.memory.data.body_md") &&
-      memoryDocumentPage.includes("data.memory.data.updated_at"),
-    "Memory Document page should read the scoped API and expose the durable document without mutation controls",
+      memoryDocumentPage.includes("data.memory.data.updated_at") &&
+      memoryDocumentPage.includes('role="alert"') &&
+      !memoryDocumentPage.includes('<pre class="memory-document-body"'),
+    "Memory Document page should read the scoped API and expose safe Markdown states without mutation controls",
   );
   assert(
     memoryStagingLoad.includes("workspaceApiPath(params.workspaceId") &&
@@ -790,19 +792,19 @@ Deno.test("Worker Console uses turn bars with hidden scrollbars and preserves sc
   const navigation = await Deno.readTextFile(new URL("./ConsoleTurnNavigation.svelte", import.meta.url));
   assert(
     !/timeline/i.test(consolePage) &&
-      consolePage.includes("const turns = $derived(consoleTurns(lines))") &&
-      consolePage.includes("<ConsoleTurnNavigation {turns} onSelect={selectConsoleTurn}") &&
+      consolePage.includes("conversationTurnPreviewsFromLines(lines)") &&
+      consolePage.includes("items={turnNavigationItems}") &&
       consolePage.includes("CSS.escape(id)") &&
       consolePage.includes("scrollbar-width: none") &&
       consolePage.includes("::-webkit-scrollbar"),
     "Console should replace the scrollbar with conversation turn navigation, not the former timeline",
   );
   assert(
-    navigation.includes("{#each turns as turn, index (turn.id)}") &&
+    navigation.includes("{#each items as turn, index (turn.turnId)}") &&
       navigation.includes('class="turn-bar"') &&
       navigation.includes("onmouseenter=") &&
       navigation.includes("onfocus=") &&
-      navigation.includes("onclick={() => onSelect(turn.id)}") &&
+      navigation.includes("onclick={() => onTurnClick(turn)}") &&
       navigation.includes('role="tooltip"') &&
       navigation.includes("aria-describedby=") &&
       navigation.includes("event.key === 'Escape'") &&

web/workspace/src/lib/workspace/markdown/DocumentCodeBlock.svelte

@@ -0,0 +1,17 @@
+<script lang="ts">
+  let {
+    lang = "",
+    text,
+  }: {
+    lang?: string;
+    text: string;
+    codeBlockStyle?: "indented";
+  } = $props();
+
+  const label = $derived(lang ? `${lang} code block` : "Code block");
+</script>
+
+<!-- svelte-ignore a11y_no_noninteractive_tabindex (horizontal scroll regions must be keyboard-focusable) -->
+<div class="markdown-code-region" role="region" aria-label={label} tabindex="0">
+  <pre><code>{text}</code></pre>
+</div>

web/workspace/src/lib/workspace/markdown/DocumentMarkdown.browser.spec.ts

@@ -0,0 +1,79 @@
+// @vitest-environment happy-dom
+
+import { cleanup, render, waitFor } from "@testing-library/svelte";
+import { afterEach, expect, test } from "vitest";
+import DocumentMarkdown from "./DocumentMarkdown.svelte";
+
+afterEach(cleanup);
+
+test("renders document Markdown semantics through the shared safe policy", async () => {
+  const source = [
+    "# Memory heading",
+    "",
+    "##### Deep heading",
+    "",
+    "###### Deepest heading",
+    "",
+    "A paragraph with **strong context** and `inline-code`.",
+    "",
+    "- first item",
+    "- second item",
+    "",
+    "> durable quote",
+    "",
+    "| Decision | Owner |",
+    "| --- | --- |",
+    "| Keep the document safe | Workspace |",
+    "",
+    "```rust",
+    'fn main() { println!("safe"); }',
+    "```",
+    "",
+    "[safe](https://example.com) [script](javascript:alert(1)) [relative](/internal)",
+    "",
+    '<img src="x" onerror="alert(1)"><script>alert(1)</script>',
+  ].join("\n");
+  const { container } = render(DocumentMarkdown, { text: source });
+
+  await waitFor(() => {
+    expect(container.querySelector("h1")?.textContent).toBe("Memory heading");
+    expect(container.querySelector("table")).not.toBeNull();
+  });
+
+  expect(container.querySelector("h5")?.textContent).toBe("Deep heading");
+  expect(container.querySelector("h6")?.textContent).toBe("Deepest heading");
+  expect(container.querySelector("strong")?.textContent).toBe("strong context");
+  expect(container.querySelectorAll("li")).toHaveLength(2);
+  expect(container.querySelector("blockquote")?.textContent).toContain(
+    "durable quote",
+  );
+  expect(container.querySelector('a[href="https://example.com"]')).not
+    .toBeNull();
+  expect(container.querySelectorAll("a")).toHaveLength(1);
+  expect(container.querySelector("img")).toBeNull();
+  expect(container.querySelector("script")).toBeNull();
+
+  const tableRegion = container.querySelector<HTMLElement>(
+    '[role="region"][aria-label="Markdown table"]',
+  );
+  const codeRegion = container.querySelector<HTMLElement>(
+    '[role="region"][aria-label="rust code block"]',
+  );
+  expect(tableRegion?.tabIndex).toBe(0);
+  expect(codeRegion?.tabIndex).toBe(0);
+  expect(codeRegion?.querySelector("pre > code")?.textContent).toContain(
+    "println!",
+  );
+});
+
+test("wraps long prose and identifiers without turning them into document-level controls", async () => {
+  const longIdentifier = "memory-identifier-".repeat(40);
+  const { container } = render(DocumentMarkdown, {
+    text:
+      `Long value: ${longIdentifier}\n\n<details open><summary>unsafe HTML</summary></details>`,
+  });
+
+  await waitFor(() => expect(container.textContent).toContain(longIdentifier));
+  expect(container.querySelector("details")).toBeNull();
+  expect(container.querySelector("button")).toBeNull();
+});

web/workspace/src/lib/workspace/markdown/DocumentMarkdown.svelte

@@ -0,0 +1,148 @@
+<script lang="ts">
+  import type { Renderers } from "@humanspeak/svelte-markdown";
+  import DocumentCodeBlock from "./DocumentCodeBlock.svelte";
+  import MarkdownTable from "./MarkdownTable.svelte";
+  import SafeMarkdown from "./SafeMarkdown.svelte";
+
+  let { text }: { text: string } = $props();
+
+  const renderers = {
+    code: DocumentCodeBlock,
+    table: MarkdownTable,
+  } satisfies Partial<Renderers>;
+</script>
+
+<SafeMarkdown {text} class="document-markdown" {renderers} />
+
+<style>
+  :global(.document-markdown) {
+    min-width: 0;
+    max-width: 100%;
+    color: var(--text);
+    font-size: var(--font-size-body);
+    line-height: var(--line-height-body);
+    overflow-wrap: anywhere;
+  }
+
+  :global(.document-markdown > :first-child) {
+    margin-top: 0;
+  }
+
+  :global(.document-markdown > :last-child) {
+    margin-bottom: 0;
+  }
+
+  :global(.document-markdown h1) {
+    margin: var(--space-6) 0 var(--space-4);
+    color: var(--text-strong);
+    font-size: var(--font-size-title);
+    line-height: var(--line-height-title);
+  }
+
+  :global(.document-markdown h2),
+  :global(.document-markdown h3),
+  :global(.document-markdown h4),
+  :global(.document-markdown h5),
+  :global(.document-markdown h6) {
+    margin: var(--space-6) 0 var(--space-2);
+    color: var(--text-strong);
+    font-size: var(--font-size-body);
+    line-height: var(--line-height-body);
+  }
+
+  :global(.document-markdown h2) {
+    font-weight: 700;
+  }
+
+  :global(.document-markdown h3),
+  :global(.document-markdown h4),
+  :global(.document-markdown h5),
+  :global(.document-markdown h6) {
+    font-weight: 600;
+  }
+
+  :global(.document-markdown p),
+  :global(.document-markdown ul),
+  :global(.document-markdown ol),
+  :global(.document-markdown blockquote),
+  :global(.document-markdown .markdown-code-region),
+  :global(.document-markdown .markdown-table-region) {
+    margin: 0 0 var(--space-4);
+  }
+
+  :global(.document-markdown ul),
+  :global(.document-markdown ol) {
+    padding-left: var(--space-5);
+  }
+
+  :global(.document-markdown li + li) {
+    margin-top: var(--space-1);
+  }
+
+  :global(.document-markdown blockquote) {
+    margin-left: 0;
+    padding-left: var(--space-4);
+    border-left: 2px solid var(--line-strong);
+    color: var(--text-muted);
+  }
+
+  :global(.document-markdown a) {
+    color: var(--accent);
+    text-underline-offset: 0.18em;
+  }
+
+  :global(.document-markdown :not(pre) > code) {
+    padding: 0 var(--space-1);
+    background: var(--bg-subtle);
+    color: var(--code);
+    overflow-wrap: anywhere;
+  }
+
+  :global(.document-markdown .markdown-code-region),
+  :global(.document-markdown .markdown-table-region) {
+    max-width: 100%;
+    overflow-x: auto;
+    overscroll-behavior-inline: contain;
+  }
+
+  :global(.document-markdown .markdown-code-region) {
+    background: var(--bg-raised);
+    color: var(--code);
+  }
+
+  :global(.document-markdown .markdown-code-region pre) {
+    width: max-content;
+    min-width: 100%;
+    margin: 0;
+    padding: var(--space-4);
+    background: transparent;
+    color: inherit;
+    white-space: pre;
+  }
+
+  :global(.document-markdown .markdown-table-region table) {
+    width: max-content;
+    min-width: 100%;
+    border-collapse: collapse;
+  }
+
+  :global(.document-markdown .markdown-table-region th),
+  :global(.document-markdown .markdown-table-region td) {
+    padding: var(--space-2) var(--space-3);
+    border-bottom: 1px solid var(--line);
+    text-align: left;
+    vertical-align: top;
+    white-space: nowrap;
+  }
+
+  :global(.document-markdown .markdown-table-region th) {
+    color: var(--text-strong);
+    font-weight: 600;
+  }
+
+  :global(.document-markdown hr) {
+    margin: var(--space-6) 0;
+    border: 0;
+    border-top: 1px solid var(--line);
+  }
+</style>

web/workspace/src/lib/workspace/markdown/MarkdownTable.svelte

@@ -0,0 +1,10 @@
+<script lang="ts">
+  import type { Snippet } from "svelte";
+
+  let { children }: { children?: Snippet } = $props();
+</script>
+
+<!-- svelte-ignore a11y_no_noninteractive_tabindex (horizontal scroll regions must be keyboard-focusable) -->
+<div class="markdown-table-region" role="region" aria-label="Markdown table" tabindex="0">
+  <table>{@render children?.()}</table>
+</div>

web/workspace/src/lib/workspace/markdown/SafeMarkdown.svelte

@@ -0,0 +1,39 @@
+<script lang="ts">
+  import SvelteMarkdown, {
+    buildUnsupportedHTML,
+    type Renderers,
+    type SvelteMarkdownProps,
+  } from "@humanspeak/svelte-markdown";
+  import MarkdownLink from "$lib/workspace/markdown/MarkdownLink.svelte";
+
+  type Props = {
+    text: string;
+    streamId?: string | number;
+    class?: string;
+    streaming?: boolean;
+    renderers?: Partial<Renderers>;
+  };
+
+  let {
+    text,
+    streamId = "static",
+    class: className = "",
+    streaming = false,
+    renderers = {},
+  }: Props = $props();
+
+  const options = {
+    breaks: true,
+    gfm: true,
+  } satisfies NonNullable<SvelteMarkdownProps["options"]>;
+
+  const safeRenderers = $derived({
+    ...renderers,
+    html: buildUnsupportedHTML(),
+    link: MarkdownLink,
+  } satisfies Partial<Renderers>);
+</script>
+
+<div class={className}>
+  <SvelteMarkdown source={text} {streamId} {options} renderers={safeRenderers} {streaming} />
+</div>

web/workspace/src/lib/workspace/settings/workdir-permissions.ts

@@ -1,6 +1,6 @@
 import type { ExternalWorkdirPermissions } from "$lib/generated/workdir-api";
 
-/** Render independent Workdir authority categories in a stable, non-conflating order. */
+/** Render an effective attachment/session capability intersection without widening it. */
 export function formatWorkdirPermissions(
   permissions: ExternalWorkdirPermissions,
 ): string {
@@ -10,3 +10,21 @@ export function formatWorkdirPermissions(
   if (permissions.command) categories.push("COMMAND");
   return categories.length > 0 ? categories.join(" · ") : "NONE";
 }
+
+/** Render one validated External grant level with its inherited authority. */
+export function formatExternalGrantPermissionLevel(
+  permissions: ExternalWorkdirPermissions,
+): string {
+  if (permissions.read && permissions.write && permissions.command) {
+    return "COMMAND (includes WRITE + READ)";
+  }
+  if (permissions.read && permissions.write && !permissions.command) {
+    return "WRITE (includes READ)";
+  }
+  if (permissions.read && !permissions.write && !permissions.command) {
+    return "READ";
+  }
+  throw new Error(
+    "External Workdir grant has a non-hierarchical permission set",
+  );
+}

web/workspace/src/routes/w/[workspaceId]/memory/+page.svelte

@@ -1,123 +1,165 @@
 <script lang="ts">
+  import DocumentMarkdown from '$lib/workspace/markdown/DocumentMarkdown.svelte';
   import { formatDate } from '$lib/workspace/api/http';
   import type { PageProps } from './$types';
 
   let { data }: PageProps = $props();
-
-  const lineCount = $derived(data.memory.data?.body_md.split('\n').length ?? 0);
 </script>
 
 <svelte:head>
-  <title>Memory Document · Yoi Workspace</title>
-  <meta name="description" content="Workspace Memory Document" />
+  <title>Memory · Yoi Workspace</title>
+  <meta name="description" content="Workspace Memory document" />
 </svelte:head>
 
-<section class="card memory-document-card">
-  <div class="detail-heading">
-    <div>
-      <p class="eyebrow">Workspace memory</p>
-      <h2>Memory Document</h2>
-    </div>
+<section class="memory-document-page" aria-label="Memory document">
   {#if data.memory.data}
-      <span>{data.memory.data.bytes} bytes</span>
-    {/if}
-  </div>
-
-  <p class="section-note">
-    Durable workspace Memory as a single Markdown document. This view is read-only.
+    <div class="memory-document-meta">
+      <p>
+        <span>Read-only</span>
+        <span aria-hidden="true">·</span>
+        <span>Updated <time datetime={data.memory.data.updated_at}>{formatDate(data.memory.data.updated_at)}</time></span>
       </p>
-
-  {#if data.memory.data}
-    <div class="memory-document-summary" aria-label="Memory document summary">
+      <details>
+        <summary>Document details</summary>
+        <dl>
           <div>
-        <span>Updated</span>
-        <strong>{formatDate(data.memory.data.updated_at)}</strong>
+            <dt>Created</dt>
+            <dd><time datetime={data.memory.data.created_at}>{formatDate(data.memory.data.created_at)}</time></dd>
           </div>
           <div>
-        <span>Created</span>
-        <strong>{formatDate(data.memory.data.created_at)}</strong>
+            <dt>Size</dt>
+            <dd>{data.memory.data.bytes} bytes</dd>
           </div>
           <div>
-        <span>Lines</span>
-        <strong>{lineCount}</strong>
-      </div>
-      <div>
-        <span>Source</span>
-        <strong>{data.memory.data.record_source}</strong>
+            <dt>Source</dt>
+            <dd><code>{data.memory.data.record_source}</code></dd>
           </div>
+        </dl>
+      </details>
     </div>
 
     {#if data.memory.data.body_md.trim().length === 0}
-      <p>No Memory document content is present.</p>
+      <div class="memory-document-state" role="status">
+        <strong>Memory document is empty.</strong>
+        <p>Durable Workspace context will appear here when it is available.</p>
+      </div>
     {:else}
-      <pre class="memory-document-body">{data.memory.data.body_md}</pre>
+      <article class="memory-document-content" aria-label="Memory document content">
+        <DocumentMarkdown text={data.memory.data.body_md} />
+      </article>
     {/if}
   {:else if data.memory.error}
-    <p class="error">{data.memory.error}</p>
+    <div class="memory-document-state memory-document-error">
+      <p role="alert"><strong>Memory document unavailable.</strong> {data.memory.error}</p>
+    </div>
   {:else}
-    <p>Waiting for <code>/api/w/{data.workspaceId}/memory</code>…</p>
+    <div class="memory-document-state" role="status">
+      <p>Memory document data is unavailable.</p>
+    </div>
   {/if}
 </section>
 
 <style>
-  .memory-document-card {
-    overflow: hidden;
-  }
-
-  .memory-document-summary {
+  .memory-document-page {
     display: grid;
-    grid-template-columns: repeat(4, minmax(0, 1fr));
-    gap: 0.75rem;
-    margin: 1rem 0;
+    flex: 0 0 auto;
+    gap: var(--space-5);
+    width: 100%;
+    min-width: 0;
+    max-width: 78rem;
+    margin-inline: auto;
   }
 
-  .memory-document-summary div {
-    border: 1px solid var(--line);
-    border-radius: 0.75rem;
-    background: var(--bg-raised);
-    padding: 0.8rem;
-  }
-
-  .memory-document-summary span {
+  .memory-document-meta {
+    display: flex;
+    align-items: baseline;
+    justify-content: space-between;
+    gap: var(--space-4);
     color: var(--text-muted);
-    display: block;
     font-size: var(--font-size-compact);
-    font-weight: 600;
-    letter-spacing: 0.04em;
-    text-transform: uppercase;
+    line-height: var(--line-height-compact);
   }
 
-  .memory-document-summary strong {
+  .memory-document-meta > p {
+    display: flex;
+    flex-wrap: wrap;
+    gap: var(--space-2);
+    margin: 0;
+  }
+
+  .memory-document-meta details {
+    flex: 0 0 auto;
+  }
+
+  .memory-document-meta summary {
+    color: var(--text-muted);
+    cursor: pointer;
+  }
+
+  .memory-document-meta dl {
+    display: grid;
+    gap: var(--space-2);
+    min-width: min(24rem, calc(100vw - (2 * var(--space-4))));
+    margin: var(--space-3) 0 0;
+    padding: var(--space-3) 0 0;
+    border-top: 1px solid var(--line);
+  }
+
+  .memory-document-meta dl > div {
+    display: grid;
+    grid-template-columns: 5rem minmax(0, 1fr);
+    gap: var(--space-3);
+  }
+
+  .memory-document-meta dt {
+    color: var(--text-faint);
+  }
+
+  .memory-document-meta dd {
+    min-width: 0;
+    margin: 0;
     color: var(--text);
-    display: block;
-    font-size: var(--font-size-compact);
-    margin-top: 0.25rem;
     overflow-wrap: anywhere;
   }
 
-  .memory-document-body {
-    background: var(--bg-raised);
-    border: 1px solid var(--line);
-    border-radius: 0.9rem;
-    color: var(--text);
-    font-family: var(--font-mono);
-    font-size: var(--font-size-body);
-    line-height: var(--line-height-body);
-    margin: 1rem 0 0;
-    overflow: auto;
-    padding: 1rem;
-    white-space: pre-wrap;
+  .memory-document-content {
+    min-width: 0;
   }
 
-  @media (max-width: 900px) {
-    .memory-document-summary {
-      grid-template-columns: repeat(2, minmax(0, 1fr));
-    }
+  .memory-document-state {
+    padding-block: var(--space-5);
+    color: var(--text-muted);
   }
 
-  @media (max-width: 640px) {
-    .memory-document-summary {
-      grid-template-columns: 1fr;
+  .memory-document-state strong {
+    color: var(--text-strong);
+  }
+
+  .memory-document-state p {
+    margin: var(--space-1) 0 0;
+  }
+
+  .memory-document-state > p:first-child {
+    margin-top: 0;
+  }
+
+  .memory-document-error,
+  .memory-document-error strong {
+    color: var(--danger);
+  }
+
+  @media (max-width: 600px) {
+    .memory-document-meta {
+      display: grid;
+      gap: var(--space-2);
+    }
+
+    .memory-document-meta details {
+      width: 100%;
+    }
+
+    .memory-document-meta dl {
+      min-width: 0;
     }
   }
 </style>

web/workspace/src/routes/w/[workspaceId]/memory/memory-page.browser.spec.ts

@@ -0,0 +1,76 @@
+// @vitest-environment happy-dom
+
+import { cleanup, render, screen, waitFor } from "@testing-library/svelte";
+import { afterEach, expect, test } from "vitest";
+import MemoryPage from "./+page.svelte";
+import type { PageProps } from "./$types";
+
+function pageProps(memory: {
+  data: {
+    body_md: string;
+    created_at: string;
+    updated_at: string;
+    bytes: number;
+    record_source: string;
+  } | null;
+  error: string | null;
+}): PageProps {
+  return {
+    data: { workspaceId: "workspace-1", memory },
+    params: { workspaceId: "workspace-1" },
+  } as unknown as PageProps;
+}
+
+afterEach(cleanup);
+
+test("makes the Markdown document primary and keeps technical metadata in disclosure", async () => {
+  const { container } = render(
+    MemoryPage,
+    pageProps({
+      data: {
+        body_md: "# Durable context\n\nRead the **current** document.",
+        created_at: "2026-01-01T00:00:00Z",
+        updated_at: "2026-01-02T03:04:05Z",
+        bytes: 48,
+        record_source: "sqlite_workspace_authority.memory_document",
+      },
+      error: null,
+    }),
+  );
+
+  await waitFor(() => {
+    expect(screen.getByRole("heading", { name: "Durable context", level: 1 })).not.toBeNull();
+  });
+  expect(screen.getByText("Read-only")).not.toBeNull();
+  expect(screen.getByText("Document details")).not.toBeNull();
+  expect(container.querySelector(".memory-document-page")?.classList.contains("card")).toBe(false);
+  expect(screen.queryByRole("heading", { name: "Memory Document" })).toBeNull();
+  expect(screen.getByRole("article", { name: "Memory document content" })).not.toBeNull();
+});
+
+test("distinguishes an empty document from request failure and unavailable data", async () => {
+  const view = render(
+    MemoryPage,
+    pageProps({
+      data: {
+        body_md: "  \n",
+        created_at: "2026-01-01T00:00:00Z",
+        updated_at: "2026-01-02T03:04:05Z",
+        bytes: 3,
+        record_source: "fixture",
+      },
+      error: null,
+    }),
+  );
+  expect(screen.getByRole("status").textContent).toContain("Memory document is empty.");
+  expect(screen.queryByRole("alert")).toBeNull();
+
+  await view.rerender(pageProps({ data: null, error: "Memory API request failed" }));
+  expect(screen.getByRole("alert").textContent).toContain("Memory document unavailable.");
+  expect(screen.getByRole("alert").textContent).toContain("Memory API request failed");
+  expect(screen.queryByText("Memory document is empty.")).toBeNull();
+
+  await view.rerender(pageProps({ data: null, error: null }));
+  expect(screen.getByRole("status").textContent).toBe("Memory document data is unavailable.");
+  expect(screen.queryByRole("alert")).toBeNull();
+});

web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/+page.svelte

@@ -3,7 +3,6 @@
     import { tick, untrack, type SvelteComponent } from "svelte";
     import ConsoleLineItem from "$lib/workspace/console/ConsoleLineItem.svelte";
     import ConsoleTurnNavigation from "$lib/workspace/console/ConsoleTurnNavigation.svelte";
-    import { consoleTurns } from "$lib/workspace/console/turn-navigation";
     import ConsoleDisplayStateView from "$lib/workspace/console/ConsoleDisplayState.svelte";
     import ConsoleTasks from "$lib/workspace/console/ConsoleTasks.svelte";
     import { namePastedImage } from "$lib/workspace/console/composer-paste";
@@ -30,7 +29,9 @@
         consoleWorkerViews,
         createConsoleProjector,
         isConsoleProjectionEvent,
+        mergeCommittedHistoryLines,
         projectConsoleLines,
+        projectSessionHistoryEntries,
         resolveConsoleViewScrollTop,
         resolveConsoleWorkerView,
         type ConsoleEventInput,
@@ -44,6 +45,7 @@
         PendingSubmissionsSnapshot,
         RewindTarget,
         Segment,
+        SessionHistoryPage,
     } from "$lib/generated/protocol";
     import {
         MAX_FILES_PER_SUBMISSION,
@@ -69,6 +71,18 @@
         type WorkerSessionRequestIdentity,
         type WorkerSessionTarget,
     } from "$lib/workspace/session-observation";
+    import {
+        applyConsoleHistoryPage,
+        beginConsoleHistoryRequest,
+        conversationTurnPreviewsFromLines,
+        emptyConsoleHistoryState,
+        failConsoleHistoryRequest,
+        historyEntries,
+        setConsoleHistoryTopEdge,
+        shouldLoadHistoryAtTop,
+        type ConsoleHistoryState,
+    } from "$lib/workspace/console/history";
+    import type { TurnNavigationItem } from "$lib/workspace/console/turn-navigation";
     import type { Diagnostic, Worker } from "$lib/workspace/sidebar/types";
 
     type Props = {
@@ -162,6 +176,7 @@
     let workerViewSelectionGeneration = 0;
     let consoleViewMode = $state<ConsoleViewMode>("overview");
     let consoleBodyElement: HTMLElement | null = null;
+    let turnNavigationElement = $state<HTMLElement | null>(null);
     let composerInputElement = $state<
         (SvelteComponent & ComposerInputHandle) | null
     >(null);
@@ -176,6 +191,8 @@
     let consoleProjection = $state.raw<ConsoleProjection>(
         consoleProjector.snapshot(),
     );
+    let historyByView = $state.raw<Record<string, ConsoleHistoryState>>({});
+    const pendingHistoryRefreshes = new Set<string>();
     let pendingObservationEvents: ConsoleEventInput[] = [];
     let pendingInitialSnapshotApplication: {
         eventId: string;
@@ -205,10 +222,30 @@
         ),
     );
     const selectedConsoleProjection = $derived(selectedWorkerView.console);
-    const lines = $derived(
+    const selectedHistoryKey = $derived(
+        `${workspaceId}:${runtimeId ?? ""}:${workerId ?? ""}:${selectedWorkerViewSessionId ?? "main"}`,
+    );
+    const selectedHistory = $derived(
+        historyByView[selectedHistoryKey] ?? emptyConsoleHistoryState(),
+    );
+    const currentLines = $derived(
         projectConsoleLines(selectedConsoleProjection.lines, consoleViewMode),
     );
-    const turns = $derived(consoleTurns(lines));
+    const committedHistoryLines = $derived(
+        projectConsoleLines(
+            projectSessionHistoryEntries(
+                historyEntries(selectedHistory),
+                selectedConsoleProjection.cwd,
+            ),
+            consoleViewMode,
+        ),
+    );
+    const lines = $derived(
+        mergeCommittedHistoryLines(committedHistoryLines, currentLines),
+    );
+    const turnNavigationItems = $derived(
+        conversationTurnPreviewsFromLines(lines),
+    );
     const tasks = $derived(selectedConsoleProjection.tasks);
     const diagnostics = $derived(
         mergeDiagnostics(worker?.diagnostics ?? [], streamDiagnostics),
@@ -264,6 +301,233 @@
         return response.json() as Promise<T>;
     }
 
+    type WorkerSessionHistoryResponse =
+        | { availability: "page"; page: SessionHistoryPage }
+        | {
+            availability: "unavailable";
+            reason: string;
+            message: string;
+        };
+
+    function mainHistoryKey(target: ConsoleTarget): string {
+        return `${target.workspaceId}:${target.runtimeId}:${target.workerId}:main`;
+    }
+
+    function historyStateFor(key: string): ConsoleHistoryState {
+        return historyByView[key] ?? emptyConsoleHistoryState();
+    }
+
+    function setHistoryState(key: string, state: ConsoleHistoryState) {
+        historyByView = { ...historyByView, [key]: state };
+    }
+
+    async function requestHistoryPage(
+        target: ConsoleTarget,
+        key: string,
+        cursor: string | null,
+        token: number,
+    ) {
+        const started = beginConsoleHistoryRequest(historyStateFor(key), cursor);
+        if (!started) return;
+        setHistoryState(key, started);
+
+        const anchors = cursor === null ? null : captureHistoryAnchors();
+        const query = new URLSearchParams({ limit: "5" });
+        if (cursor) query.set("cursor", cursor);
+        const path = workerApiPath(
+            `/runtimes/${encodeURIComponent(target.runtimeId)}/workers/${encodeURIComponent(target.workerId)}/session/history?${query}`,
+        );
+        try {
+            const response = await fetch(path, {
+                credentials: "same-origin",
+                headers: { accept: "application/json" },
+            });
+            if (response.status === 404 || response.status === 405) {
+                throw new Error("Earlier conversation is not supported by this Runtime version.");
+            }
+            if (!response.ok) {
+                throw new Error(`History request failed (${response.status}).`);
+            }
+            const payload = (await response.json()) as WorkerSessionHistoryResponse;
+            if (token !== reloadToken || mainHistoryKey(target) !== key) return;
+            if (pendingHistoryRefreshes.has(key)) return;
+            if (payload.availability === "unavailable") {
+                setHistoryState(
+                    key,
+                    failConsoleHistoryRequest(historyStateFor(key), payload.message),
+                );
+                return;
+            }
+            setHistoryState(
+                key,
+                applyConsoleHistoryPage(historyStateFor(key), payload.page, cursor),
+            );
+            await tick();
+            restoreHistoryAnchors(anchors);
+        } catch (error) {
+            if (
+                token !== reloadToken ||
+                mainHistoryKey(target) !== key ||
+                pendingHistoryRefreshes.has(key)
+            )
+                return;
+            setHistoryState(
+                key,
+                failConsoleHistoryRequest(
+                    historyStateFor(key),
+                    error instanceof Error ? error.message : String(error),
+                ),
+            );
+        } finally {
+            const refreshAgain = pendingHistoryRefreshes.delete(key);
+            if (
+                refreshAgain &&
+                token === reloadToken &&
+                mainHistoryKey(target) === key
+            ) {
+                const stale = historyStateFor(key);
+                setHistoryState(key, {
+                    ...stale,
+                    status: stale.turns.length > 0 ? "ready" : "idle",
+                    error: null,
+                    requestedCursor: null,
+                });
+                void requestHistoryPage(target, key, null, token);
+            }
+        }
+    }
+
+    type HistoryAnchor = { id: string; top: number };
+    type HistoryAnchors = {
+        transcript: HistoryAnchor | null;
+        navigation: HistoryAnchor | null;
+    };
+
+    function captureElementAnchor(
+        container: HTMLElement | null,
+        selector: string,
+        dataKey: "consoleLineId" | "turnId",
+    ): HistoryAnchor | null {
+        const first = container?.querySelector<HTMLElement>(selector);
+        const id = first?.dataset[dataKey] ?? "";
+        return first && id ? { id, top: first.getBoundingClientRect().top } : null;
+    }
+
+    function captureHistoryAnchors(): HistoryAnchors {
+        return {
+            transcript: captureElementAnchor(
+                consoleBodyElement,
+                "[data-console-line-id]",
+                "consoleLineId",
+            ),
+            navigation: captureElementAnchor(
+                turnNavigationElement,
+                "[data-turn-id]",
+                "turnId",
+            ),
+        };
+    }
+
+    function restoreElementAnchor(
+        container: HTMLElement | null,
+        selector: string,
+        anchor: HistoryAnchor | null,
+    ) {
+        if (!anchor || !container) return;
+        const target = container.querySelector<HTMLElement>(selector);
+        if (!target) return;
+        container.scrollTop += target.getBoundingClientRect().top - anchor.top;
+    }
+
+    function restoreHistoryAnchors(anchors: HistoryAnchors | null) {
+        if (!anchors) return;
+        restoreElementAnchor(
+            consoleBodyElement,
+            `[data-console-line-id="${CSS.escape(anchors.transcript?.id ?? "")}"]`,
+            anchors.transcript,
+        );
+        restoreElementAnchor(
+            turnNavigationElement,
+            `[data-turn-id="${CSS.escape(anchors.navigation?.id ?? "")}"]`,
+            anchors.navigation,
+        );
+    }
+
+    function loadEarlierHistory() {
+        const target = consoleTarget;
+        if (!target || selectedWorkerViewSessionId !== null) return;
+        const key = mainHistoryKey(target);
+        const state = historyStateFor(key);
+        if (!state.hasMore || !state.cursor) return;
+        void requestHistoryPage(target, key, state.cursor, reloadToken);
+    }
+
+    function retryHistoryLoad() {
+        const target = consoleTarget;
+        if (!target || selectedWorkerViewSessionId !== null) return;
+        const key = mainHistoryKey(target);
+        const state = historyStateFor(key);
+        void requestHistoryPage(
+            target,
+            key,
+            state.hasMore ? state.cursor : null,
+            reloadToken,
+        );
+    }
+
+    function fenceCurrentHistoryForRewind() {
+        const target = consoleTarget;
+        if (!target) return;
+        const key = mainHistoryKey(target);
+        const current = historyStateFor(key);
+        const loading = current.status === "loading";
+        const reset = emptyConsoleHistoryState();
+        setHistoryState(key, {
+            ...reset,
+            status: loading ? "loading" : "idle",
+            requestedCursor: loading ? current.requestedCursor : null,
+            topEdgeArmed: current.topEdgeArmed,
+        });
+        if (loading) pendingHistoryRefreshes.add(key);
+    }
+
+    function refreshCurrentHistory() {
+        const target = consoleTarget;
+        if (!target) return;
+        const key = mainHistoryKey(target);
+        if (historyStateFor(key).status === "loading") {
+            pendingHistoryRefreshes.add(key);
+            return;
+        }
+        void requestHistoryPage(target, key, null, reloadToken);
+    }
+
+    function handleHistoryTopEdge(atTop: boolean) {
+        if (selectedWorkerViewSessionId !== null) return;
+        const key = selectedHistoryKey;
+        const state = historyStateFor(key);
+        if (shouldLoadHistoryAtTop(state, atTop)) {
+            loadEarlierHistory();
+        } else if (!atTop) {
+            const rearmed = setConsoleHistoryTopEdge(state, false);
+            if (rearmed !== state) setHistoryState(key, rearmed);
+        }
+    }
+
+    function jumpToConversationTurn(item: TurnNavigationItem) {
+        const line = lines.find(
+            (candidate) => candidate.entryId === item.lineId || candidate.id === item.lineId,
+        );
+        const target = line
+            ? consoleBodyElement?.querySelector(
+                `[data-console-line-id="${CSS.escape(line.id)}"]`,
+            )
+            : null;
+        if (target instanceof HTMLElement && line) {
+            selectConsoleTurn(line.id);
+        }
+    }
+
     async function loadWorker(target: ConsoleTarget, token: number) {
         workerError = null;
         try {
@@ -406,6 +670,22 @@
             liveWorkerState = consoleProjection.status === "shutdown"
                 ? "shutdown"
                 : workerStateFromSnapshot(consoleProjection.workerState);
+            if (
+                eventBatch.some((event) => event.event.event === "rewind_applied")
+            ) {
+                fenceCurrentHistoryForRewind();
+            }
+            if (
+                eventBatch.some((event) =>
+                    event.event.event === "snapshot" ||
+                    event.event.event === "segment_rotated" ||
+                    event.event.event === "rewind_applied" ||
+                    event.event.event === "user_message" ||
+                    event.event.event === "session_entry_committed"
+                )
+            ) {
+                refreshCurrentHistory();
+            }
             if (
                 initialSnapshotApplication &&
                 eventBatch.some(
@@ -1338,6 +1618,7 @@
         }
         autoFollowConsole = isNearConsoleBottom(consoleBodyElement);
         rememberConsoleWorkerViewScroll();
+        handleHistoryTopEdge(consoleBodyElement.scrollTop <= 1);
     }
 
     async function scrollConsoleToBottom() {
@@ -1556,6 +1837,24 @@
                     <p class="error">{workerError}</p>
                 {/if}
 
+                {#if selectedWorkerViewSessionId === null && (selectedHistory.hasMore || selectedHistory.error || selectedHistory.status === "loading")}
+                    <div class="conversation-history-boundary">
+                        <button
+                            type="button"
+                            disabled={selectedHistory.status === "loading"}
+                            onclick={selectedHistory.error ? retryHistoryLoad : loadEarlierHistory}
+                        >
+                            {selectedHistory.status === "loading"
+                                ? "Loading earlier conversation…"
+                                : selectedHistory.error
+                                  ? "Earlier conversation unavailable · retry"
+                                  : "Earlier conversation available · load 5 turns"}
+                        </button>
+                    </div>
+                {:else if selectedWorkerViewSessionId === null && selectedHistory.status === "ready"}
+                    <div class="conversation-history-boundary complete">Start of conversation</div>
+                {/if}
+
                 <ConsoleDisplayStateView
                     state={consoleDisplayState}
                     hasContent={lines.length > 0}
@@ -1572,11 +1871,20 @@
                 {/if}
             </article>
         </div>
-            {#if (consoleDisplayState.kind === "ready" || consoleDisplayState.kind === "stale") && turns.length > 0}
-                {#key `${workerId}:${selectedWorkerView.sessionId}`}
-                    <ConsoleTurnNavigation {turns} onSelect={selectConsoleTurn} />
-                {/key}
-            {/if}
+
+            <ConsoleTurnNavigation
+                items={turnNavigationItems}
+                hasMore={selectedWorkerViewSessionId === null && selectedHistory.hasMore}
+                loading={selectedHistory.status === "loading"}
+                error={selectedWorkerViewSessionId === null
+                    ? selectedHistory.error
+                    : "Earlier history is unavailable for direct SubWorker views."}
+                onLoadMore={selectedHistory.error ? retryHistoryLoad : loadEarlierHistory}
+                onTopEdgeChange={handleHistoryTopEdge}
+                onTurnClick={jumpToConversationTurn}
+                historyAvailable={selectedWorkerViewSessionId === null}
+                bind:element={turnNavigationElement}
+            />
         </section>
 
         {#if taskPaneOpen}
@@ -2041,6 +2349,36 @@
         display: none;
     }
 
+    .conversation-history-boundary {
+        display: flex;
+        justify-content: center;
+        color: var(--text-muted);
+        font-size: var(--font-size-compact);
+        padding-bottom: var(--space-3);
+    }
+
+    .conversation-history-boundary button {
+        border: 0;
+        background: transparent;
+        color: var(--tui-cyan);
+        cursor: pointer;
+        font: inherit;
+    }
+
+    .conversation-history-boundary button:disabled {
+        cursor: wait;
+        opacity: 0.65;
+    }
+
+    .conversation-history-boundary.complete::before,
+    .conversation-history-boundary.complete::after {
+        content: "";
+        align-self: center;
+        width: 2rem;
+        margin: 0 var(--space-2);
+        border-top: 1px solid var(--line);
+    }
+
     .pending-submissions {
         display: grid;
         grid-template-columns: repeat(2, minmax(0, 1fr));

web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/console-display.browser.spec.ts

@@ -6,10 +6,12 @@ import {
   render,
   screen,
   waitFor,
+  within,
 } from "@testing-library/svelte";
 import { afterEach, beforeEach, expect, test, vi } from "vitest";
 import type {
   Event as ProtocolEvent,
+  SessionConversationTurn,
   SessionSnapshot,
 } from "$lib/generated/protocol";
 import type { Worker } from "$lib/workspace/sidebar/types";
@@ -106,6 +108,63 @@ function sessionWithUserMessage(content: string): SessionSnapshot {
   };
 }
 
+function emptyHistoryPage() {
+  return {
+    availability: "page",
+    page: {
+      session_id: "session-a",
+      lineage_id: "lineage-a",
+      compact_ancestor_lineage_ids: [],
+      turns: [],
+      next_cursor: null,
+      has_more: false,
+    },
+  };
+}
+
+function historyPage(
+  indices: number[],
+  cursor: string | null,
+  lineageId = "lineage-a",
+  parentLineage?: {
+    lineage_id: string;
+    adopted_through_turn?: SessionConversationTurn | null;
+  },
+) {
+  return {
+    availability: "page",
+    page: {
+      session_id: "session-a",
+      lineage_id: lineageId,
+      compact_ancestor_lineage_ids: [],
+      parent_lineage: parentLineage,
+      turns: indices.map((index) => ({
+        turn_id: `user-${index}`,
+        entries: [
+          {
+            entry_id: `user-${index}`,
+            timestamp: index,
+            provenance: "human_input",
+            kind: "message",
+            role: "user",
+            content: [{ kind: "text", text: `question ${index}` }],
+          },
+          {
+            entry_id: `assistant-${index}`,
+            timestamp: index,
+            provenance: "model_output",
+            kind: "message",
+            role: "assistant",
+            content: [{ kind: "text", text: `done ${index}` }],
+          },
+        ],
+      })),
+      next_cursor: cursor,
+      has_more: cursor !== null,
+    },
+  };
+}
+
 function snapshotEvent(session = emptySession()): ProtocolEvent {
   return {
     event: "snapshot",
@@ -367,18 +426,30 @@ test("applies retained empty and nonempty snapshots before showing their read-on
     snapshot: sessionWithUserMessage("retained message"),
   }));
 
-  expect(await screen.findByText("retained message")).not.toBeNull();
+  expect(
+    await within(screen.getByRole("article", { name: "main transcript" }))
+      .findByText("retained message"),
+  ).not.toBeNull();
   expect(screen.getByText("Read-only retained conversation")).not.toBeNull();
   expect(screen.queryByText("No conversation to display")).toBeNull();
 });
 
 test("shows bounded initial failures and retries explicitly", async () => {
-  const fetchMock = vi.fn()
-    .mockResolvedValueOnce(new Response(null, { status: 503 }))
-    .mockResolvedValueOnce(Response.json({
+  let sessionRequests = 0;
+  const fetchMock = vi.fn((input: RequestInfo | URL) => {
+    if (String(input).includes("/session/history")) {
+      return Promise.resolve(Response.json(emptyHistoryPage()));
+    }
+    sessionRequests += 1;
+    return Promise.resolve(
+      sessionRequests === 1
+        ? new Response(null, { status: 503 })
+        : Response.json({
           availability: "retained_snapshot",
           snapshot: emptySession(),
-    }));
+        }),
+    );
+  });
   vi.stubGlobal("fetch", fetchMock);
   render(ConsolePage, { data: pageData() });
 
@@ -388,7 +459,7 @@ test("shows bounded initial failures and retries explicitly", async () => {
   await fireEvent.click(screen.getByRole("button", { name: "Retry" }));
 
   expect(await screen.findByText("No conversation to display")).not.toBeNull();
-  expect(fetchMock).toHaveBeenCalledTimes(2);
+  expect(sessionRequests).toBe(2);
 });
 
 test("distinguishes typed unavailability and an initial live connection closure", async () => {
@@ -426,17 +497,165 @@ test("preserves rendered content while reconnecting", async () => {
   latestListener().onFrame(
     subscribedFrame(sessionWithUserMessage("kept message")),
   );
-  expect(await screen.findByText("kept message")).not.toBeNull();
+  expect(
+    await within(screen.getByRole("article", { name: "main transcript" }))
+      .findByText("kept message"),
+  ).not.toBeNull();
 
   latestListener().onStatus?.("closed", "Workspace subscription disconnected");
   expect(await screen.findByText("Conversation updates are unavailable")).not
     .toBeNull();
-  expect(screen.getByText("kept message")).not.toBeNull();
+  expect(
+    within(screen.getByRole("article", { name: "main transcript" })).getByText(
+      "kept message",
+    ),
+  ).not.toBeNull();
   expect(screen.queryByText("No conversation to display")).toBeNull();
 
   latestListener().onStatus?.("connecting", "resubscribing");
   expect(await screen.findByText("Refreshing conversation")).not.toBeNull();
-  expect(screen.getByText("kept message")).not.toBeNull();
+  expect(
+    within(screen.getByRole("article", { name: "main transcript" })).getByText(
+      "kept message",
+    ),
+  ).not.toBeNull();
+});
+
+test("reconnect snapshot refreshes lineage and removes stale sibling history", async () => {
+  let historyRequests = 0;
+  vi.stubGlobal(
+    "fetch",
+    vi.fn((input: RequestInfo | URL) => {
+      if (!String(input).includes("/session/history")) {
+        return Promise.resolve(
+          Response.json({ availability: "live_protocol" }),
+        );
+      }
+      historyRequests += 1;
+      const response = historyPage([historyRequests], null);
+      if (historyRequests === 2) {
+        response.page.lineage_id = "lineage-b";
+      }
+      return Promise.resolve(Response.json(response));
+    }),
+  );
+
+  render(ConsolePage, { data: pageData() });
+  await waitFor(() => expect(multiplexer.subscribe).toHaveBeenCalledOnce());
+  latestListener().onFrame(
+    subscribedFrame(sessionWithUserMessage("lineage A current")),
+  );
+  await waitFor(() =>
+    expectHistoryTurn("question 1")
+  );
+
+  latestListener().onStatus?.("closed", "disconnected during rewind");
+  latestListener().onStatus?.("connecting", "reconnecting");
+  latestListener().onFrame(
+    subscribedFrame(sessionWithUserMessage("lineage B current")),
+  );
+
+  await waitFor(() =>
+    expectHistoryTurn("question 2")
+  );
+  expect(screen.queryByText("question 1")).toBeNull();
+  expect(historyRequests).toBe(2);
+});
+
+test("snapshot supersedes an in-flight page before stale lineage can render", async () => {
+  const staleHistory = deferred<Response>();
+  let historyRequests = 0;
+  vi.stubGlobal(
+    "fetch",
+    vi.fn((input: RequestInfo | URL) => {
+      if (!String(input).includes("/session/history")) {
+        return Promise.resolve(
+          Response.json({ availability: "live_protocol" }),
+        );
+      }
+      historyRequests += 1;
+      if (historyRequests === 1) return staleHistory.promise;
+      const response = historyPage([2], null);
+      response.page.lineage_id = "lineage-b";
+      return Promise.resolve(Response.json(response));
+    }),
+  );
+
+  render(ConsolePage, { data: pageData() });
+  await waitFor(() => expect(multiplexer.subscribe).toHaveBeenCalledOnce());
+  latestListener().onFrame(
+    subscribedFrame(sessionWithUserMessage("lineage A current")),
+  );
+  await waitFor(() => expect(historyRequests).toBe(1));
+
+  latestListener().onFrame(
+    subscribedFrame(sessionWithUserMessage("lineage B current")),
+  );
+  staleHistory.resolve(Response.json(historyPage([1], null)));
+
+  await waitFor(() =>
+    expectHistoryTurn("question 2")
+  );
+  expect(screen.queryByText("question 1")).toBeNull();
+  expect(historyRequests).toBe(2);
+});
+
+test("fork refresh reconciles an in-flight older page to the adopted prefix", async () => {
+  const staleOlder = deferred<Response>();
+  let historyRequests = 0;
+  vi.stubGlobal(
+    "fetch",
+    vi.fn((input: RequestInfo | URL) => {
+      if (!String(input).includes("/session/history")) {
+        return Promise.resolve(
+          Response.json({ availability: "live_protocol" }),
+        );
+      }
+      historyRequests += 1;
+      if (historyRequests === 1) {
+        return Promise.resolve(
+          Response.json(historyPage([46, 47, 48, 49, 50], "older-46")),
+        );
+      }
+      if (historyRequests === 2) return staleOlder.promise;
+      return Promise.resolve(Response.json(historyPage(
+        [101, 102, 103, 104, 105],
+        "older-101",
+        "lineage-fork",
+        {
+          lineage_id: "lineage-a",
+          adopted_through_turn: historyPage([48], null).page
+            .turns[0] as SessionConversationTurn,
+        },
+      )));
+    }),
+  );
+
+  render(ConsolePage, { data: pageData() });
+  await waitFor(() => expect(multiplexer.subscribe).toHaveBeenCalledOnce());
+  latestListener().onFrame(subscribedFrame());
+  await waitFor(() =>
+    expectHistoryTurn("question 50")
+  );
+
+  const transcriptScroller = screen.getByLabelText("main transcript")
+    .parentElement as HTMLElement;
+  transcriptScroller.scrollTop = 0;
+  await fireEvent.scroll(transcriptScroller);
+  await waitFor(() => expect(historyRequests).toBe(2));
+
+  latestListener().onFrame(
+    subscribedFrame(sessionWithUserMessage("fork current")),
+  );
+  staleOlder.resolve(Response.json(historyPage([41, 42, 43, 44, 45], null)));
+
+  await waitFor(() =>
+    expectHistoryTurn("question 101")
+  );
+  expectHistoryTurn("question 48");
+  expect(screen.queryByText("question 49")).toBeNull();
+  expectHistoryTurn("question 41");
+  expect(historyRequests).toBe(3);
 });
 
 test("route changes clear prior content and fence stale Session responses", async () => {
@@ -444,6 +663,9 @@ test("route changes clear prior content and fence stale Session responses", asyn
   const current = deferred<Response>();
   let firstWorkerLoads = 0;
   const fetchMock = vi.fn((input: RequestInfo | URL) => {
+    if (String(input).includes("/session/history")) {
+      return Promise.resolve(Response.json(emptyHistoryPage()));
+    }
     if (String(input).includes("worker-b")) {
       return current.promise.then((value) => value.clone());
     }
@@ -459,7 +681,10 @@ test("route changes clear prior content and fence stale Session responses", asyn
   latestListener().onFrame(
     subscribedFrame(sessionWithUserMessage("previous worker content")),
   );
-  expect(await screen.findByText("previous worker content")).not.toBeNull();
+  expect(
+    await within(screen.getByRole("article", { name: "main transcript" }))
+      .findByText("previous worker content"),
+  ).not.toBeNull();
 
   latestListener().onStatus?.("closed", "reload old worker");
   await fireEvent.click(
@@ -467,7 +692,10 @@ test("route changes clear prior content and fence stale Session responses", asyn
   );
   await waitFor(() => expect(firstWorkerLoads).toBe(2));
   await view.rerender({ data: pageData("worker-b", "runtime-b") });
-  expect(screen.queryByText("previous worker content")).toBeNull();
+  expect(
+    within(screen.getByRole("article", { name: "main transcript" }))
+      .queryByText("previous worker content"),
+  ).toBeNull();
   expect(screen.getByRole("status").textContent).toContain(
     "Loading conversation",
   );
@@ -476,7 +704,12 @@ test("route changes clear prior content and fence stale Session responses", asyn
     availability: "retained_snapshot",
     snapshot: sessionWithUserMessage("current worker content"),
   }));
-  expect(await screen.findByText("current worker content")).not.toBeNull();
+  expect(
+    await within(screen.getByRole("article", { name: "main transcript" }))
+      .findByText(
+        "current worker content",
+      ),
+  ).not.toBeNull();
 
   staleReload.resolve(Response.json({
     availability: "unavailable",
@@ -484,6 +717,213 @@ test("route changes clear prior content and fence stale Session responses", asyn
   }));
   await settleMicrotasks();
   expect(screen.queryByText("stale worker error")).toBeNull();
-  expect(screen.queryByText("previous worker content")).toBeNull();
-  expect(screen.getByText("current worker content")).not.toBeNull();
+  expect(
+    within(screen.getByRole("article", { name: "main transcript" }))
+      .queryByText("previous worker content"),
+  ).toBeNull();
+  expect(
+    within(screen.getByRole("article", { name: "main transcript" })).getByText(
+      "current worker content",
+    ),
+  ).not.toBeNull();
 });
+
+test("loads retained conversation turns five at a time into the log and turn bar", async () => {
+  const historyPages = [
+    {
+      availability: "page",
+      page: {
+        session_id: "session-a",
+        lineage_id: "lineage-a",
+        compact_ancestor_lineage_ids: [],
+        turns: [8, 9, 10, 11, 12].map((index) => ({
+          turn_id: `user-${index}`,
+          entries: [
+            {
+              entry_id: `user-${index}`,
+              timestamp: index,
+              provenance: "human_input",
+              kind: "message",
+              role: "user",
+              content: [{ kind: "text", text: `question ${index}` }],
+            },
+            {
+              entry_id: `assistant-${index}`,
+              timestamp: index,
+              provenance: "model_output",
+              kind: "message",
+              role: "assistant",
+              content: [{ kind: "text", text: `done ${index}` }],
+            },
+          ],
+        })),
+        next_cursor: "older-8",
+        has_more: true,
+      },
+    },
+    {
+      availability: "page",
+      page: {
+        session_id: "session-a",
+        lineage_id: "lineage-a",
+        compact_ancestor_lineage_ids: [],
+        turns: [3, 4, 5, 6, 7].map((index) => ({
+          turn_id: `user-${index}`,
+          entries: [{
+            entry_id: `user-${index}`,
+            timestamp: index,
+            provenance: "human_input",
+            kind: "message",
+            role: "user",
+            content: [{ kind: "text", text: `question ${index}` }],
+          }],
+        })),
+        next_cursor: "older-3",
+        has_more: true,
+      },
+    },
+    historyPage([1, 2], null),
+  ];
+  let historyRequests = 0;
+  vi.stubGlobal(
+    "fetch",
+    vi.fn((input: RequestInfo | URL) => {
+      if (String(input).includes("/session/history")) {
+        return Promise.resolve(Response.json(historyPages[historyRequests++]));
+      }
+      return Promise.resolve(Response.json({ availability: "live_protocol" }));
+    }),
+  );
+
+  render(ConsolePage, { data: pageData() });
+  await waitFor(() => expect(multiplexer.subscribe).toHaveBeenCalledOnce());
+  latestListener().onFrame(subscribedFrame());
+
+  await waitFor(() =>
+    expectHistoryTurn("question 8")
+  );
+  expect(screen.getAllByText("done 12")).toHaveLength(1);
+  const transcriptScroller = screen.getByLabelText("main transcript")
+    .parentElement as HTMLElement;
+  transcriptScroller.scrollTop = 0;
+  await fireEvent.scroll(transcriptScroller);
+  await waitFor(() =>
+    expectHistoryTurn("question 3")
+  );
+  expect(historyRequests).toBe(2);
+
+  const navigation = screen.getByLabelText("Conversation turns");
+  const navigationList = navigation.firstElementChild as HTMLElement;
+  navigationList.scrollTop = 0;
+  await fireEvent.scroll(navigationList);
+  await fireEvent.scroll(navigationList);
+  transcriptScroller.scrollTop = 0;
+  await fireEvent.scroll(transcriptScroller);
+  await settleMicrotasks();
+  expect(historyRequests).toBe(2);
+
+  await fireEvent.click(
+    screen.getByRole("button", {
+      name: "Earlier conversation available · load 5 turns",
+    }),
+  );
+  await waitFor(() =>
+    expectHistoryTurn("question 1")
+  );
+  expect(screen.getAllByText("Start of conversation")).toHaveLength(1);
+  expect(historyRequests).toBe(3);
+
+  const target = screen.getByText("question 8").closest(".console-line") as HTMLElement;
+  vi.spyOn(target, "getBoundingClientRect").mockReturnValue({ top: 600 } as DOMRect);
+  vi.spyOn(transcriptScroller, "getBoundingClientRect").mockReturnValue({ top: 200 } as DOMRect);
+  Object.defineProperties(transcriptScroller, {
+    scrollHeight: { configurable: true, value: 2000 },
+    clientHeight: { configurable: true, value: 400 },
+  });
+  transcriptScroller.scrollTop = 400;
+  await fireEvent.click(
+    screen.getByRole("button", {
+      name: /^Turn \d+: question 8$/,
+    }),
+  );
+  expect(transcriptScroller.scrollTop).toBe(800);
+});
+
+test("keeps live content when history fails and retries the bounded page explicitly", async () => {
+  let historyRequests = 0;
+  vi.stubGlobal(
+    "fetch",
+    vi.fn((input: RequestInfo | URL) => {
+      if (String(input).includes("/session/history")) {
+        historyRequests += 1;
+        return Promise.resolve(
+          historyRequests === 1
+            ? new Response(null, { status: 503 })
+            : Response.json(historyPage([1, 2, 3, 4], null)),
+        );
+      }
+      return Promise.resolve(Response.json({ availability: "live_protocol" }));
+    }),
+  );
+
+  render(ConsolePage, { data: pageData() });
+  await waitFor(() => expect(multiplexer.subscribe).toHaveBeenCalledOnce());
+  latestListener().onFrame(
+    subscribedFrame(sessionWithUserMessage("current response remains")),
+  );
+
+  expect(
+    await within(screen.getByRole("article", { name: "main transcript" }))
+      .findByText("current response remains"),
+  ).not.toBeNull();
+  await fireEvent.click(
+    await screen.findByRole("button", {
+      name: "Earlier conversation unavailable · retry",
+    }),
+  );
+  await waitFor(() =>
+    expectHistoryTurn("question 1")
+  );
+  expect(historyRequests).toBe(2);
+  expect(
+    within(screen.getByRole("article", { name: "main transcript" })).getByText(
+      "current response remains",
+    ),
+  ).not.toBeNull();
+  expect(screen.getAllByText("Start of conversation")).toHaveLength(1);
+});
+
+test("fences delayed history pages when the selected Worker route changes", async () => {
+  const stale = deferred<Response>();
+  vi.stubGlobal(
+    "fetch",
+    vi.fn((input: RequestInfo | URL) => {
+      const path = String(input);
+      if (path.includes("/session/history")) {
+        return path.includes("worker-b")
+          ? Promise.resolve(Response.json(historyPage([21], null)))
+          : stale.promise;
+      }
+      return Promise.resolve(Response.json({
+        availability: "retained_snapshot",
+        snapshot: emptySession(),
+      }));
+    }),
+  );
+
+  const view = render(ConsolePage, { data: pageData() });
+  await view.rerender({ data: pageData("worker-b", "runtime-b") });
+  await waitFor(() =>
+    expectHistoryTurn("question 21")
+  );
+
+  stale.resolve(Response.json(historyPage([99], null)));
+  await settleMicrotasks();
+  expect(screen.queryByText("question 99")).toBeNull();
+  expectHistoryTurn("question 21");
+});
+
+function expectHistoryTurn(text: string) {
+  expect(screen.getAllByText(text)).toHaveLength(1);
+  expect(screen.getByRole("button", { name: new RegExp("^Turn \\d+: " + text + "$") })).not.toBeNull();
+}

web/workspace/src/routes/w/[workspaceId]/workers/new/+page.svelte

@@ -12,7 +12,7 @@
     parseWorkerLaunchOptionsResponse,
   } from '$lib/workspace/api/workers';
   import { formatCurrentWorkdirRevision } from '$lib/workspace/settings/workdir-revision';
-  import { formatWorkdirPermissions } from '$lib/workspace/settings/workdir-permissions';
+  import { formatExternalGrantPermissionLevel } from '$lib/workspace/settings/workdir-permissions';
   import {
     buildCreateWorkspaceWorkerRequest,
     defaultWorkerLaunchForm,
@@ -40,7 +40,7 @@
       : null;
     const label = directory.display_name ?? repositoryKey ?? 'External Workdir';
     if (directory.source.kind === 'external_grant') {
-      return `${label} · External · ${formatWorkdirPermissions(directory.source.grant_permissions)}`;
+      return `${label} · External · ${formatExternalGrantPermissionLevel(directory.source.grant_permissions)}`;
     }
     return `${label} · ${formatCurrentWorkdirRevision(directory, provider)}`;
   }

web/workspace/tests/workdir-api.test.ts

@@ -56,7 +56,7 @@ Deno.test("Workdir REST validation accepts External grant sources without Runtim
       source: {
         kind: "external_grant",
         grant_id: "grant-1",
-        grant_permissions: { read: true, write: false, command: true },
+        grant_permissions: { read: true, write: true, command: true },
       },
       materializer_kind: "client_hosted_external",
       status: "active",
@@ -72,7 +72,7 @@ Deno.test("Workdir REST validation accepts External grant sources without Runtim
   }
   if (
     !detail.item.source.grant_permissions.read ||
-    detail.item.source.grant_permissions.write ||
+    !detail.item.source.grant_permissions.write ||
     !detail.item.source.grant_permissions.command
   ) {
     throw new Error("External Workdir grant permissions were not preserved");
@@ -83,6 +83,11 @@ Deno.test("Workdir REST validation rejects missing or misplaced External grant p
   for (
     const source of [
       { kind: "external_grant", grant_id: "grant-1" },
+      {
+        kind: "external_grant",
+        grant_id: "grant-1",
+        grant_permissions: { read: false, write: false, command: true },
+      },
       {
         kind: "external_grant",
         grant_id: "grant-1",
@@ -113,7 +118,11 @@ Deno.test("Workdir REST validation rejects missing or misplaced External grant p
       rejected = true;
     }
     if (!rejected) {
-      throw new Error(`invalid External permission projection was accepted: ${JSON.stringify(source)}`);
+      throw new Error(
+        `invalid External permission projection was accepted: ${
+          JSON.stringify(source)
+        }`,
+      );
     }
   }
 });

web/workspace/tests/workdir-permissions.test.ts

@@ -2,9 +2,12 @@ declare const Deno: {
   test(name: string, fn: () => void | Promise<void>): void;
 };
 
-import { formatWorkdirPermissions } from "../src/lib/workspace/settings/workdir-permissions.ts";
+import {
+  formatExternalGrantPermissionLevel,
+  formatWorkdirPermissions,
+} from "../src/lib/workspace/settings/workdir-permissions.ts";
 
-Deno.test("Workdir permissions render independent categories in stable order", () => {
+Deno.test("effective Workdir permissions render partial intersections without widening", () => {
   const cases = [
     [{ read: true, write: false, command: false }, "READ"],
     [{ read: true, write: true, command: false }, "READ · WRITE"],
@@ -20,3 +23,32 @@ Deno.test("Workdir permissions render independent categories in stable order", (
     }
   }
 });
+
+Deno.test("External grant levels show inherited authority and reject partial grants", () => {
+  const cases = [
+    [{ read: true, write: false, command: false }, "READ"],
+    [{ read: true, write: true, command: false }, "WRITE (includes READ)"],
+    [
+      { read: true, write: true, command: true },
+      "COMMAND (includes WRITE + READ)",
+    ],
+  ] as const;
+  for (const [permissions, expected] of cases) {
+    const actual = formatExternalGrantPermissionLevel(permissions);
+    if (actual !== expected) {
+      throw new Error(`expected ${expected}, got ${actual}`);
+    }
+  }
+
+  let rejected = false;
+  try {
+    formatExternalGrantPermissionLevel({
+      read: false,
+      write: false,
+      command: true,
+    });
+  } catch {
+    rejected = true;
+  }
+  if (!rejected) throw new Error("command-only External grant was accepted");
+});