diff --git a/crates/client/src/backend_runtime.rs b/crates/client/src/backend_runtime.rs
index 76cc5884a..3acf5a36f 100644
--- a/crates/client/src/backend_runtime.rs
+++ b/crates/client/src/backend_runtime.rs
@@ -5,7 +5,6 @@ pub use server_api::{
     CreateWorkspaceWorkerRequest as BackendCreateWorkerRequest, Diagnostic as BackendDiagnostic,
     DiagnosticSeverity as BackendDiagnosticSeverity, ListResponse as BackendRuntimeListResponse,
     RuntimeSummary as BackendRuntimeSummary,
-    WorkerCapabilitySummary as BackendWorkerCapabilitySummary,
     WorkerImplementationSummary as BackendWorkerImplementationSummary,
     WorkerLaunchOptionsResponse as BackendWorkerLaunchOptions,
     WorkerLaunchProfileCandidate as BackendWorkerLaunchProfileCandidate,
@@ -869,7 +868,6 @@ mod tests {
                 "pinned": false,
                 "retention_state": "resident",
                 "implementation": {"kind": "embedded", "display_hint": "Embedded"},
-                "capabilities": {"can_stop": true, "can_spawn_followup": false},
                 "diagnostics": []
             },
             "diagnostics": []
@@ -952,10 +950,11 @@ mod tests {
             "label": "Coder",
             "workspace": {"visibility": "workspace", "identity": "workspace"},
             "state": "idle",
+            "availability": "observed",
             "implementation": {"kind": "worker", "display_hint": "Coder"},
-            "capabilities": {"can_stop": true, "can_spawn_followup": false},
             "workdir_attachments": [{
                 "alias": "checkout",
+                "effective_permissions": {"read": true, "write": true, "command": true},
                 "working_directory": {
                     "working_directory_id": "wd-1",
                     "source": {"kind": "repository", "repository_key": "main"},
diff --git a/crates/client/src/lib.rs b/crates/client/src/lib.rs
index 4627b87ff..32e1c1a10 100644
--- a/crates/client/src/lib.rs
+++ b/crates/client/src/lib.rs
@@ -24,7 +24,7 @@ pub use backend_runtime::{
     BackendCreateWorkerRequest, BackendCreateWorkerResponse, BackendDiagnostic,
     BackendDiagnosticSeverity, BackendRuntimeClientError, BackendRuntimeListResponse,
     BackendRuntimeListTarget, BackendRuntimeSummary, BackendRuntimeTarget,
-    BackendWorkerCapabilitySummary, BackendWorkerImplementationSummary, BackendWorkerLaunchOptions,
+    BackendWorkerImplementationSummary, BackendWorkerLaunchOptions,
     BackendWorkerLaunchProfileCandidate, BackendWorkerLaunchRuntimeOption,
     BackendWorkerLaunchTarget, BackendWorkerOperationState, BackendWorkerRestoreResponse,
     BackendWorkerRestoreResult, BackendWorkerRestoreState, BackendWorkerSummary,
diff --git a/crates/client/src/workspace_product.rs b/crates/client/src/workspace_product.rs
index 32a360451..6426efafd 100644
--- a/crates/client/src/workspace_product.rs
+++ b/crates/client/src/workspace_product.rs
@@ -1029,7 +1029,7 @@ mod tests {
             ),
             (
                 "200 OK",
-                r#"{"workspace_id":"workspace-a","runtime_id":"embedded","worker_id":"worker-1","console_href":"/w/workspace-a/workers/worker-1","worker":{"runtime_id":"embedded","worker_id":"worker-1","host_id":"embedded","display_name":"Intake","label":"worker-1","profile":"builtin:intake","singleton_key":null,"tags":[],"workspace":{"visibility":"workspace","identity":"workspace-a","workspace_id":"workspace-a"},"state":"idle","last_seen_at":null,"pinned":false,"retention_state":"active","implementation":{"kind":"runtime","display_hint":"Runtime Worker"},"capabilities":{"can_stop":true,"can_spawn_followup":false},"diagnostics":[]},"diagnostics":[]}"#,
+                r#"{"workspace_id":"workspace-a","runtime_id":"embedded","worker_id":"worker-1","console_href":"/w/workspace-a/workers/worker-1","worker":{"runtime_id":"embedded","worker_id":"worker-1","host_id":"embedded","display_name":"Intake","label":"worker-1","profile":"builtin:intake","singleton_key":null,"tags":[],"workspace":{"visibility":"workspace","identity":"workspace-a","workspace_id":"workspace-a"},"state":"idle","last_seen_at":null,"pinned":false,"retention_state":"active","implementation":{"kind":"runtime","display_hint":"Runtime Worker"},"diagnostics":[]},"diagnostics":[]}"#,
             ),
         ]);
         let client = BackendWorkspaceProductClient::new_with_access_token(
@@ -1057,7 +1057,7 @@ mod tests {
 
     #[test]
     fn workspace_orchestrator_launch_uses_scoped_backend_route() {
-        let body = r#"{"workspace_id":"workspace-a","online":true,"disposition":"created","worker":{"runtime_id":"embedded","worker_id":"worker-2","host_id":"embedded","display_name":"Orchestrator","label":"worker-2","profile":"builtin:orchestrator","singleton_key":"workspace-orchestrator","tags":[],"workspace":{"visibility":"workspace","identity":"workspace-a","workspace_id":"workspace-a"},"state":"idle","last_seen_at":null,"pinned":true,"retention_state":"active","implementation":{"kind":"runtime","display_hint":"Runtime Worker"},"capabilities":{"can_stop":true,"can_spawn_followup":false},"diagnostics":[]},"diagnostics":[]}"#;
+        let body = r#"{"workspace_id":"workspace-a","online":true,"disposition":"created","worker":{"runtime_id":"embedded","worker_id":"worker-2","host_id":"embedded","display_name":"Orchestrator","label":"worker-2","profile":"builtin:orchestrator","singleton_key":"workspace-orchestrator","tags":[],"workspace":{"visibility":"workspace","identity":"workspace-a","workspace_id":"workspace-a"},"state":"idle","last_seen_at":null,"pinned":true,"retention_state":"active","implementation":{"kind":"runtime","display_hint":"Runtime Worker"},"diagnostics":[]},"diagnostics":[]}"#;
         let (base_url, request, handle) = one_response_server("200 OK", body);
         let client = BackendWorkspaceProductClient::new_with_access_token(
             base_url,
diff --git a/crates/server-api/src/lib.rs b/crates/server-api/src/lib.rs
index 5b14e83c9..bff7dbe1e 100644
--- a/crates/server-api/src/lib.rs
+++ b/crates/server-api/src/lib.rs
@@ -6892,7 +6892,6 @@ pub struct RuntimeWorkerSummary {
     #[serde(default)]
     pub retention_state: String,
     pub implementation: WorkerImplementationSummary,
-    pub capabilities: WorkerCapabilitySummary,
     #[serde(default, skip_serializing_if = "Vec::is_empty")]
     pub workdir_attachments: Vec<serde_json::Value>,
     #[serde(default)]
@@ -7888,13 +7887,6 @@ pub struct WorkerImplementationSummary {
     pub display_hint: String,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
-#[cfg_attr(feature = "typescript", derive(ts_rs::TS))]
-pub struct WorkerCapabilitySummary {
-    pub can_stop: bool,
-    pub can_spawn_followup: bool,
-}
-
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq, JsonSchema)]
 #[cfg_attr(feature = "typescript", derive(ts_rs::TS))]
 #[serde(tag = "kind", rename_all = "snake_case", deny_unknown_fields)]
@@ -8120,7 +8112,6 @@ pub struct WorkerSummary {
     #[serde(default)]
     pub retention_state: String,
     pub implementation: WorkerImplementationSummary,
-    pub capabilities: WorkerCapabilitySummary,
     #[serde(default, skip_serializing_if = "Vec::is_empty")]
     pub workdir_attachments: Vec<WorkerWorkdirAttachmentSummary>,
     #[serde(default)]
@@ -8163,7 +8154,6 @@ pub struct WorkerLaunchWorkerSummary {
     pub pinned: bool,
     pub retention_state: String,
     pub implementation: WorkerImplementationSummary,
-    pub capabilities: WorkerCapabilitySummary,
     #[serde(default, skip_serializing_if = "Vec::is_empty")]
     pub workdir_attachments: Vec<RuntimeWorkerWorkdirAttachmentSummary>,
     #[serde(default)]
@@ -9339,7 +9329,6 @@ pub fn worker_launch_api_typescript() -> String {
         WorkingDirectorySummary::decl(&config),
         WorkerWorkspaceSummary::decl(&config),
         WorkerImplementationSummary::decl(&config),
-        WorkerCapabilitySummary::decl(&config),
         RuntimeWorkerWorkdirAttachmentSummary::decl(&config),
         WorkerLaunchWorkerSummary::decl(&config),
         WorkerLaunchRuntimeOption::decl(&config),
@@ -10308,10 +10297,6 @@ mod tests {
                 kind: "runtime".to_string(),
                 display_hint: "Runtime Worker".to_string(),
             },
-            capabilities: WorkerCapabilitySummary {
-                can_stop: true,
-                can_spawn_followup: false,
-            },
             workdir_attachments: Vec::new(),
             diagnostics: Vec::new(),
         }
@@ -10791,7 +10776,6 @@ mod tests {
             },
             "state": "idle",
             "implementation": {"kind": "worker", "display_hint": "Coder"},
-            "capabilities": {"can_stop": true, "can_spawn_followup": false}
         });
 
         assert!(serde_json::from_value::<WorkerSummary>(payload).is_err());
diff --git a/crates/tui/src/backend_worker_picker.rs b/crates/tui/src/backend_worker_picker.rs
index 8fa950f51..0b67597cb 100644
--- a/crates/tui/src/backend_worker_picker.rs
+++ b/crates/tui/src/backend_worker_picker.rs
@@ -552,9 +552,8 @@ fn working_directory_text(worker: &BackendWorkerSummary) -> String {
 mod tests {
     use super::*;
     use client::{
-        BackendDiagnostic, BackendDiagnosticSeverity, BackendWorkerCapabilitySummary,
-        BackendWorkerImplementationSummary, BackendWorkerRestoreResult,
-        BackendWorkerWorkspaceSummary,
+        BackendDiagnostic, BackendDiagnosticSeverity, BackendWorkerImplementationSummary,
+        BackendWorkerRestoreResult, BackendWorkerWorkspaceSummary,
     };
 
     fn worker(runtime_id: &str, worker_id: &str, profile: Option<&str>) -> BackendWorkerSummary {
@@ -588,10 +587,6 @@ mod tests {
                 kind: "embedded".to_string(),
                 display_hint: "embedded".to_string(),
             },
-            capabilities: BackendWorkerCapabilitySummary {
-                can_stop: true,
-                can_spawn_followup: false,
-            },
             workdir_attachments: Vec::new(),
             diagnostics: Vec::new(),
         }
diff --git a/crates/worker-runtime/src/worker_source.rs b/crates/worker-runtime/src/worker_source.rs
index cb4d322f2..1a7e5d4da 100644
--- a/crates/worker-runtime/src/worker_source.rs
+++ b/crates/worker-runtime/src/worker_source.rs
@@ -1298,7 +1298,9 @@ mod tests {
 
     #[test]
     fn runtime_owned_workspace_client_has_no_fixed_request_timeout() {
-        let (base_url, server) = delayed_workspace_response(Duration::from_millis(75));
+        // This must exceed reqwest::blocking::Client's default 30-second timeout.
+        // A short delay only checks our Option field, not the effective HTTP deadline.
+        let (base_url, server) = delayed_workspace_response(Duration::from_secs(31));
         let client =
             RuntimeOwnedWorkspaceClient::new("workspace-a", base_url, "runtime-a", "worker-a");
         assert_eq!(client.request_timeout, None);
diff --git a/crates/workspace-server/src/hosts.rs b/crates/workspace-server/src/hosts.rs
index 2e8fd65b1..6e86ec96a 100644
--- a/crates/workspace-server/src/hosts.rs
+++ b/crates/workspace-server/src/hosts.rs
@@ -240,12 +240,6 @@ pub struct InternalWorkerImplementationSummary {
     pub display_hint: String,
 }
 
-#[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
-pub struct InternalWorkerCapabilitySummary {
-    pub can_stop: bool,
-    pub can_spawn_followup: bool,
-}
-
 #[derive(Debug, Clone, Serialize, Deserialize, PartialEq, Eq)]
 pub struct InternalWorkerSummary {
     #[serde(flatten)]
@@ -273,7 +267,6 @@ pub struct InternalWorkerSummary {
     #[serde(default)]
     pub retention_state: String,
     pub implementation: InternalWorkerImplementationSummary,
-    pub capabilities: InternalWorkerCapabilitySummary,
     #[serde(default, skip_serializing_if = "Vec::is_empty")]
     pub workdir_attachments: Vec<WorkingDirectoryAttachmentStatus>,
     pub diagnostics: Vec<RuntimeDiagnostic>,
@@ -384,10 +377,6 @@ pub(crate) fn workspace_worker_summary(
             kind: summary.implementation.kind,
             display_hint: summary.implementation.display_hint,
         },
-        capabilities: server_api::WorkerCapabilitySummary {
-            can_stop: summary.capabilities.can_stop,
-            can_spawn_followup: summary.capabilities.can_spawn_followup,
-        },
         workdir_attachments,
         diagnostics: summary.diagnostics.into_iter().map(Into::into).collect(),
     }
@@ -2231,10 +2220,6 @@ impl EmbeddedWorkerRuntime {
         Some(EmbeddedWorkerRef::new(EmbeddedWorkerId::parse(worker_id)?))
     }
 
-    fn can_stop_embedded_worker(&self, status: EmbeddedWorkerStatus) -> bool {
-        runtime_worker_can_stop(self.execution_enabled, status)
-    }
-
     fn map_worker_summary(
         &self,
         summary: worker_runtime::catalog::WorkerSummary,
@@ -2274,11 +2259,6 @@ impl EmbeddedWorkerRuntime {
                 kind: "embedded_worker_runtime".to_string(),
                 display_hint: "backend-internal worker-runtime Worker".to_string(),
             },
-            capabilities: InternalWorkerCapabilitySummary {
-                can_stop: summary.execution_metadata_available
-                    && self.can_stop_embedded_worker(summary.status),
-                can_spawn_followup: false,
-            },
             workdir_attachments: summary.workdir_attachments,
             diagnostics: embedded_worker_projection_diagnostics(
                 summary.execution_metadata_available,
@@ -2319,11 +2299,6 @@ impl EmbeddedWorkerRuntime {
                 kind: "embedded_worker_runtime".to_string(),
                 display_hint: "backend-internal worker-runtime Worker".to_string(),
             },
-            capabilities: InternalWorkerCapabilitySummary {
-                can_stop: detail.execution_metadata_available
-                    && self.can_stop_embedded_worker(detail.status),
-                can_spawn_followup: false,
-            },
             workdir_attachments: detail.workdir_attachments,
             diagnostics: embedded_worker_projection_diagnostics(
                 detail.execution_metadata_available,
@@ -4127,11 +4102,6 @@ impl RemoteWorkerRuntime {
                 kind: "remote_worker_runtime".to_string(),
                 display_hint: "Backend-proxied remote worker-runtime Worker".to_string(),
             },
-            capabilities: InternalWorkerCapabilitySummary {
-                can_stop: summary.execution_metadata_available
-                    && runtime_worker_can_stop(true, summary.status),
-                can_spawn_followup: false,
-            },
             workdir_attachments: summary.workdir_attachments,
             diagnostics: remote_worker_projection_diagnostics(summary.execution_metadata_available),
         }
@@ -4170,11 +4140,6 @@ impl RemoteWorkerRuntime {
                 kind: "remote_worker_runtime".to_string(),
                 display_hint: "Backend-proxied remote worker-runtime Worker".to_string(),
             },
-            capabilities: InternalWorkerCapabilitySummary {
-                can_stop: detail.execution_metadata_available
-                    && runtime_worker_can_stop(true, detail.status),
-                can_spawn_followup: false,
-            },
             workdir_attachments: detail.workdir_attachments,
             diagnostics: remote_worker_projection_diagnostics(detail.execution_metadata_available),
         }
@@ -5152,10 +5117,6 @@ fn embedded_runtime_status_label(status: RuntimeStatus) -> &'static str {
     }
 }
 
-fn runtime_worker_can_stop(execution_enabled: bool, status: EmbeddedWorkerStatus) -> bool {
-    execution_enabled && status.is_active()
-}
-
 fn embedded_worker_status_label(status: EmbeddedWorkerStatus) -> &'static str {
     match status {
         EmbeddedWorkerStatus::Idle => "idle",
@@ -5963,10 +5924,6 @@ pub fn placeholder_worker(host_id: impl Into<String>) -> InternalWorkerSummary {
             kind: "placeholder".to_string(),
             display_hint: "unsupported".to_string(),
         },
-        capabilities: InternalWorkerCapabilitySummary {
-            can_stop: false,
-            can_spawn_followup: false,
-        },
         workdir_attachments: Vec::new(),
         diagnostics: vec![diagnostic(
             "runtime_capability_unsupported",
@@ -6621,10 +6578,6 @@ mod tests {
                         kind: "fixture".to_string(),
                         display_hint: "test fixture".to_string(),
                     },
-                    capabilities: InternalWorkerCapabilitySummary {
-                        can_stop: false,
-                        can_spawn_followup: false,
-                    },
                     workdir_attachments: Vec::new(),
                     diagnostics: Vec::new(),
                 }],
@@ -7123,7 +7076,12 @@ mod tests {
         let spawned = runtime.spawn_worker(test_create_binding(), embedded_spawn_request());
         assert_eq!(spawned.state, InternalWorkerOperationState::Accepted);
         let worker = spawned.worker.expect("created embedded worker");
-        assert!(worker.capabilities.can_stop);
+        assert!(
+            serde_json::to_value(&worker)
+                .unwrap()
+                .get("capabilities")
+                .is_none()
+        );
 
         let input = runtime.send_input(
             &worker.worker.worker_id,
@@ -7496,7 +7454,12 @@ mod tests {
             workers.items[0].workspace.identity,
             "runtime_registry_worker"
         );
-        assert!(workers.items[0].capabilities.can_stop);
+        assert!(
+            serde_json::to_value(&workers.items[0])
+                .unwrap()
+                .get("capabilities")
+                .is_none()
+        );
 
         let input = registry
             .send_input(
@@ -7581,11 +7544,14 @@ mod tests {
 
         let workers = registry.list_workers(10);
         assert_eq!(workers.items.len(), 5);
-        assert!(!workers.items[0].capabilities.can_stop);
-        assert!(workers.items[1].capabilities.can_stop);
-        assert!(workers.items[2].capabilities.can_stop);
-        assert!(workers.items[3].capabilities.can_stop);
-        assert!(!workers.items[4].capabilities.can_stop);
+        for worker in &workers.items {
+            assert!(
+                serde_json::to_value(worker)
+                    .unwrap()
+                    .get("capabilities")
+                    .is_none()
+            );
+        }
         assert_eq!(workers.items[0].state, "stopped");
         assert_eq!(workers.items[1].state, "running");
         assert_eq!(workers.items[2].state, "paused");
@@ -7601,7 +7567,12 @@ mod tests {
         let stopped_detail = registry
             .worker(&RuntimeWorkerRef::new("remote:primary", &worker_id))
             .unwrap();
-        assert!(!stopped_detail.capabilities.can_stop);
+        assert!(
+            serde_json::to_value(&stopped_detail)
+                .unwrap()
+                .get("capabilities")
+                .is_none()
+        );
         assert_eq!(stopped_detail.state, "stopped");
 
         server.join().expect("mock remote server finished");
diff --git a/crates/workspace-server/src/server.rs b/crates/workspace-server/src/server.rs
index 8e38123e9..d933b23b4 100644
--- a/crates/workspace-server/src/server.rs
+++ b/crates/workspace-server/src/server.rs
@@ -152,17 +152,16 @@ use crate::companion::{
 use crate::config_source::ConfigCommitRequest;
 use crate::hosts::{
     EMBEDDED_RUNTIME_ID, EmbeddedWorkerRuntime, HostDiagnosticSeverity, InternalHostSummary,
-    InternalWorkerCapabilitySummary, InternalWorkerImplementationSummary,
-    InternalWorkerOperationState, InternalWorkerRestoreResult, InternalWorkerSummary,
-    InternalWorkerWorkspaceSummary, RemoteRuntimeConfig, RemoteWorkerRuntime, RuntimeDiagnostic,
-    RuntimePingFailureKind, RuntimeRegistry, RuntimeRegistryError, RuntimeRegistryUnregisterResult,
-    TicketWorkerRole, WorkerCompletionsRequest, WorkerCompletionsResult, WorkerControlOperation,
-    WorkerCreateBinding, WorkerInputKind, WorkerInputRequest, WorkerInputResult,
-    WorkerLifecycleRequest, WorkerLifecycleResult, WorkerSpawnAcceptanceRequirement,
-    WorkerSpawnIntent, WorkerSpawnRequest, WorkerSpawnResult, WorkerSpawnWorkingDirectoryRequest,
-    WorkerTicketAssignmentRequest, WorkspaceRuntimeAuthorization,
-    is_disallowed_remote_runtime_address, is_loopback_runtime_origin,
-    worker_spawn_create_fingerprint, workspace_worker_summary,
+    InternalWorkerImplementationSummary, InternalWorkerOperationState, InternalWorkerRestoreResult,
+    InternalWorkerSummary, InternalWorkerWorkspaceSummary, RemoteRuntimeConfig,
+    RemoteWorkerRuntime, RuntimeDiagnostic, RuntimePingFailureKind, RuntimeRegistry,
+    RuntimeRegistryError, RuntimeRegistryUnregisterResult, TicketWorkerRole,
+    WorkerCompletionsRequest, WorkerCompletionsResult, WorkerControlOperation, WorkerCreateBinding,
+    WorkerInputKind, WorkerInputRequest, WorkerInputResult, WorkerLifecycleRequest,
+    WorkerLifecycleResult, WorkerSpawnAcceptanceRequirement, WorkerSpawnIntent, WorkerSpawnRequest,
+    WorkerSpawnResult, WorkerSpawnWorkingDirectoryRequest, WorkerTicketAssignmentRequest,
+    WorkspaceRuntimeAuthorization, is_disallowed_remote_runtime_address,
+    is_loopback_runtime_origin, worker_spawn_create_fingerprint, workspace_worker_summary,
 };
 use crate::memory_backend::execute_memory_backend_operation_with_authority;
 use crate::memory_staging::{
@@ -5175,10 +5174,6 @@ fn runtime_worker_summary_to_api(
             kind: worker.implementation.kind,
             display_hint: worker.implementation.display_hint,
         },
-        capabilities: server_api::WorkerCapabilitySummary {
-            can_stop: worker.capabilities.can_stop,
-            can_spawn_followup: worker.capabilities.can_spawn_followup,
-        },
         workdir_attachments: worker
             .workdir_attachments
             .into_iter()
@@ -16956,10 +16951,6 @@ fn worker_launch_worker_summary(worker: InternalWorkerSummary) -> WorkerLaunchWo
             kind: worker.implementation.kind,
             display_hint: worker.implementation.display_hint,
         },
-        capabilities: server_api::WorkerCapabilitySummary {
-            can_stop: worker.capabilities.can_stop,
-            can_spawn_followup: worker.capabilities.can_spawn_followup,
-        },
         workdir_attachments: worker
             .workdir_attachments
             .into_iter()
@@ -24806,10 +24797,6 @@ fn worker_summary_from_registry(record: &WorkerRegistryRecord) -> InternalWorker
         last_seen_at: Some(record.updated_at.clone()),
         pinned: record.retention_state == "pinned",
         retention_state: record.retention_state.clone(),
-        capabilities: InternalWorkerCapabilitySummary {
-            can_stop: false,
-            can_spawn_followup: false,
-        },
         workspace: InternalWorkerWorkspaceSummary {
             visibility: "backend_registry".to_string(),
             identity: record.workspace_id.clone(),
@@ -24855,8 +24842,6 @@ fn worker_summary_from_projection(
         .then(|| observation.worker.worker_state.clone())
         .flatten();
     summary.last_seen_at = Some(observation.observed_at.clone());
-    summary.capabilities.can_stop = observed
-        && observation.worker.state != protocol::subscription::SubscriptionWorkerState::Stopped;
     summary.implementation.display_hint = if observed {
         "Runtime-backed Worker".to_string()
     } else {
@@ -26709,7 +26694,12 @@ mod tests {
         assert_eq!(unavailable.availability, availability);
         assert_eq!(unavailable.state, "unavailable");
         assert_eq!(unavailable.worker_state, None);
-        assert!(!unavailable.capabilities.can_stop);
+        assert!(
+            serde_json::to_value(&unavailable)
+                .unwrap()
+                .get("capabilities")
+                .is_none()
+        );
 
         let mut observed_stopped = projection;
         let observation = observed_stopped.observation.as_mut().unwrap();
@@ -28645,10 +28635,6 @@ mod tests {
                     kind: "fixture".to_string(),
                     display_hint: "Workdirless fixture".to_string(),
                 },
-                capabilities: InternalWorkerCapabilitySummary {
-                    can_stop: true,
-                    can_spawn_followup: false,
-                },
                 workdir_attachments: Vec::new(),
                 diagnostics: Vec::new(),
             }
@@ -40983,10 +40969,6 @@ mod tests {
                     kind: "remote".to_string(),
                     display_hint: "remote".to_string(),
                 },
-                capabilities: server_api::WorkerCapabilitySummary {
-                    can_stop: true,
-                    can_spawn_followup: false,
-                },
                 workdir_attachments: Vec::new(),
                 diagnostics: Vec::new(),
             }
@@ -41081,10 +41063,6 @@ mod tests {
                     kind: "remote".to_string(),
                     display_hint: "remote".to_string(),
                 },
-                capabilities: server_api::WorkerCapabilitySummary {
-                    can_stop: true,
-                    can_spawn_followup: false,
-                },
                 workdir_attachments: Vec::new(),
                 diagnostics: Vec::new(),
             }],
@@ -43445,7 +43423,12 @@ mod tests {
         // catalog remains controllable while its failed execution is represented in
         // `worker_state` rather than by removing the catalog Worker.
         assert_eq!(restored_worker.state, "idle");
-        assert!(restored_worker.capabilities.can_stop);
+        assert!(
+            serde_json::to_value(&restored_worker)
+                .unwrap()
+                .get("capabilities")
+                .is_none()
+        );
 
         let bundles = restored
             .runtime
diff --git a/openapi/server-api.json b/openapi/server-api.json
index bc652123f..197279460 100644
--- a/openapi/server-api.json
+++ b/openapi/server-api.json
@@ -7448,9 +7448,6 @@
             "$ref": "#/components/schemas/SubscriptionWorkerAvailability",
             "description": "Freshness of the Runtime observation used to construct `worker_state`.\n`Unavailable` means no current controller snapshot is being asserted."
           },
-          "capabilities": {
-            "$ref": "#/components/schemas/WorkerCapabilitySummary"
-          },
           "diagnostics": {
             "default": [],
             "items": {
@@ -7550,7 +7547,6 @@
           "availability",
           "state",
           "implementation",
-          "capabilities",
           "updated_at"
         ],
         "type": "object"
@@ -7791,9 +7787,6 @@
       "RuntimeWorkerSummary": {
         "additionalProperties": false,
         "properties": {
-          "capabilities": {
-            "$ref": "#/components/schemas/WorkerCapabilitySummary"
-          },
           "diagnostics": {
             "default": [],
             "items": {
@@ -7872,8 +7865,7 @@
           "label",
           "workspace",
           "state",
-          "implementation",
-          "capabilities"
+          "implementation"
         ],
         "type": "object"
       },
@@ -11254,21 +11246,6 @@
           }
         ]
       },
-      "WorkerCapabilitySummary": {
-        "properties": {
-          "can_spawn_followup": {
-            "type": "boolean"
-          },
-          "can_stop": {
-            "type": "boolean"
-          }
-        },
-        "required": [
-          "can_stop",
-          "can_spawn_followup"
-        ],
-        "type": "object"
-      },
       "WorkerFileDeleteResponse": {
         "additionalProperties": false,
         "properties": {
@@ -11447,9 +11424,6 @@
         "additionalProperties": false,
         "description": "Runtime-owned Worker summary embedded in Worker launch responses.\n\nThis preserves the existing launch wire shape. Workspace-owned Worker list\nand detail responses use [`WorkerSummary`] instead.",
         "properties": {
-          "capabilities": {
-            "$ref": "#/components/schemas/WorkerCapabilitySummary"
-          },
           "diagnostics": {
             "default": [],
             "items": {
@@ -11529,8 +11503,7 @@
           "state",
           "pinned",
           "retention_state",
-          "implementation",
-          "capabilities"
+          "implementation"
         ],
         "type": "object"
       },
@@ -11830,9 +11803,6 @@
             "$ref": "#/components/schemas/SubscriptionWorkerAvailability",
             "description": "Freshness of the Runtime observation used to construct `worker_state`.\n`Unavailable` means no current controller snapshot is being asserted."
           },
-          "capabilities": {
-            "$ref": "#/components/schemas/WorkerCapabilitySummary"
-          },
           "diagnostics": {
             "default": [],
             "items": {
@@ -11928,8 +11898,7 @@
           "workspace",
           "availability",
           "state",
-          "implementation",
-          "capabilities"
+          "implementation"
         ],
         "type": "object"
       },
@@ -14020,7 +13989,7 @@
   "info": {
     "title": "Yoi Server API",
     "version": "0.1.0",
-    "x-yoi-source-digest": "sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0"
+    "x-yoi-source-digest": "sha256:ae559492220ec118f04c2c0c9593e8b3cb44c3cb857be3ae85715ace26da8043"
   },
   "openapi": "3.1.0",
   "paths": {
diff --git a/tools/web-ux/browser-tests/console_history_fixture_server.ts b/tools/web-ux/browser-tests/console_history_fixture_server.ts
index 53035f71b..22830dcbf 100644
--- a/tools/web-ux/browser-tests/console_history_fixture_server.ts
+++ b/tools/web-ux/browser-tests/console_history_fixture_server.ts
@@ -31,7 +31,6 @@ const worker = {
   profile: "default",
   tags: [],
   diagnostics: [],
-  capabilities: { can_stop: false, can_spawn_followup: false },
   workspace: {
     workspace_id: workspaceId,
     visibility: "workspace",
diff --git a/web/workspace/src/lib/generated/companion-api.ts b/web/workspace/src/lib/generated/companion-api.ts
index 428524f66..5bf2a6295 100644
--- a/web/workspace/src/lib/generated/companion-api.ts
+++ b/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 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
+// Input contract: 0.1.0 (sha256:ae559492220ec118f04c2c0c9593e8b3cb44c3cb857be3ae85715ace26da8043)
 // 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
diff --git a/web/workspace/src/lib/generated/repository-api.ts b/web/workspace/src/lib/generated/repository-api.ts
index 8f11ef780..06819d7c5 100644
--- a/web/workspace/src/lib/generated/repository-api.ts
+++ b/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 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
+// Input contract: 0.1.0 (sha256:ae559492220ec118f04c2c0c9593e8b3cb44c3cb857be3ae85715ace26da8043)
 // 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
@@ -61,8 +61,6 @@ export type SubscriptionWorkerAvailability = "observed" | "unavailable";
 
 export type WorkerBusyState = { kind: "run"; state: WorkerRunState; } | { kind: "maintenance"; state: WorkerMaintenanceState; };
 
-export type WorkerCapabilitySummary = { can_spawn_followup: boolean; can_stop: boolean; };
-
 export type WorkerImplementationSummary = { display_hint: string; kind: string; };
 
 export type WorkerMaintenanceState = "compacting";
@@ -73,7 +71,7 @@ export type WorkerState = { kind: "idle"; } | { kind: "busy"; state: WorkerBusyS
 
 export type WorkerStateSnapshot = { last_command_id: number; state: WorkerState; };
 
-export type WorkerSummary = { availability: SubscriptionWorkerAvailability; capabilities: WorkerCapabilitySummary; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
+export type WorkerSummary = { availability: SubscriptionWorkerAvailability; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
 
 export type WorkerWorkdirAttachmentSummary = { alias: string; effective_permissions: ExternalWorkdirPermissions; working_directory: WorkingDirectorySummary; };
 
diff --git a/web/workspace/src/lib/generated/runtime-api.ts b/web/workspace/src/lib/generated/runtime-api.ts
index 686626a14..c18141c5c 100644
--- a/web/workspace/src/lib/generated/runtime-api.ts
+++ b/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 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
+// Input contract: 0.1.0 (sha256:ae559492220ec118f04c2c0c9593e8b3cb44c3cb857be3ae85715ace26da8043)
 // 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
@@ -107,7 +107,7 @@ export type RuntimeWorkerLifecycleResult = { diagnostics?: Array<Diagnostic>; ru
 
 export type RuntimeWorkerListResponse = { diagnostics?: Array<Diagnostic>; items: Array<WorkerSummary>; limit: number; source: string; workspace_id: string; };
 
-export type RuntimeWorkerShowResponse = { availability: SubscriptionWorkerAvailability; capabilities: WorkerCapabilitySummary; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; updated_at: string; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
+export type RuntimeWorkerShowResponse = { availability: SubscriptionWorkerAvailability; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; updated_at: string; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
 
 export type RuntimeWorkerSpawnAcceptanceEvidence = { detail: string; kind: string; };
 
@@ -123,7 +123,7 @@ export type RuntimeWorkerSpawnWorkingDirectoryAttachmentRequest = { alias: strin
 
 export type RuntimeWorkerSpawnWorkingDirectoryRequest = { repository_key: string; selector?: string | null; };
 
-export type RuntimeWorkerSummary = { capabilities: WorkerCapabilitySummary; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<unknown>; worker_id: string; worker_state?: unknown; workspace: WorkerWorkspaceSummary; };
+export type RuntimeWorkerSummary = { diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<unknown>; worker_id: string; worker_state?: unknown; workspace: WorkerWorkspaceSummary; };
 
 export type RuntimeWorkerTicketAssignmentRequest = { operation_id: string; ticket_id: string; };
 
@@ -137,8 +137,6 @@ export type UploadedFileRef = { artifact_id: string; availability: UploadedFileA
 
 export type WorkerBusyState = { kind: "run"; state: WorkerRunState; } | { kind: "maintenance"; state: WorkerMaintenanceState; };
 
-export type WorkerCapabilitySummary = { can_spawn_followup: boolean; can_stop: boolean; };
-
 export type WorkerFileDeleteResponse = { deleted: boolean; };
 
 export type WorkerFileUploadResponse = { file: UploadedFileRef; };
@@ -163,7 +161,7 @@ export type WorkerState = { kind: "idle"; } | { kind: "busy"; state: WorkerBusyS
 
 export type WorkerStateSnapshot = { last_command_id: number; state: WorkerState; };
 
-export type WorkerSummary = { availability: SubscriptionWorkerAvailability; capabilities: WorkerCapabilitySummary; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
+export type WorkerSummary = { availability: SubscriptionWorkerAvailability; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
 
 export type WorkerWorkdirAttachmentSummary = { alias: string; effective_permissions: ExternalWorkdirPermissions; working_directory: WorkingDirectorySummary; };
 
diff --git a/web/workspace/src/lib/generated/ticket-api.ts b/web/workspace/src/lib/generated/ticket-api.ts
index 875171af6..5b2262e05 100644
--- a/web/workspace/src/lib/generated/ticket-api.ts
+++ b/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 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
+// Input contract: 0.1.0 (sha256:ae559492220ec118f04c2c0c9593e8b3cb44c3cb857be3ae85715ace26da8043)
 // 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
diff --git a/web/workspace/src/lib/generated/worker-launch-api.ts b/web/workspace/src/lib/generated/worker-launch-api.ts
index 8692625e9..61770c180 100644
--- a/web/workspace/src/lib/generated/worker-launch-api.ts
+++ b/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 (sha256:49856606e4a16d138cc04a62a6096fd40fff213587b1cbf7f0594f28994a45b0)
+// Input contract: 0.1.0 (sha256:ae559492220ec118f04c2c0c9593e8b3cb44c3cb857be3ae85715ace26da8043)
 // 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
@@ -45,8 +45,6 @@ export type UploadedFileRef = { artifact_id: string; availability: UploadedFileA
 
 export type WorkerBusyState = { kind: "run"; state: WorkerRunState; } | { kind: "maintenance"; state: WorkerMaintenanceState; };
 
-export type WorkerCapabilitySummary = { can_spawn_followup: boolean; can_stop: boolean; };
-
 export type WorkerImplementationSummary = { display_hint: string; kind: string; };
 
 export type WorkerLaunchOptionsResponse = { default_profile?: string | null; diagnostics: Array<Diagnostic>; profiles: Array<WorkerLaunchProfileCandidate>; repositories: Array<WorkingDirectoryRepositoryOption>; runtimes: Array<WorkerLaunchRuntimeOption>; working_directories: Array<WorkingDirectorySummary>; workspace_id: string; };
@@ -55,7 +53,7 @@ export type WorkerLaunchProfileCandidate = { description: string; id: string; la
 
 export type WorkerLaunchRuntimeOption = { built_in: boolean; diagnostics: Array<Diagnostic>; display_name: string; runtime_id: string; status: string; worker_creation_available: boolean; working_directory_required: boolean; };
 
-export type WorkerLaunchWorkerSummary = { capabilities: WorkerCapabilitySummary; diagnostics?: Array<Diagnostic>; display_name: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned: boolean; profile?: string | null; retention_state: string; runtime_id: string; singleton_key?: string | null; state: string; tags: Array<string>; workdir_attachments?: Array<RuntimeWorkerWorkdirAttachmentSummary>; worker_id: string; workspace: WorkerWorkspaceSummary; };
+export type WorkerLaunchWorkerSummary = { diagnostics?: Array<Diagnostic>; display_name: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned: boolean; profile?: string | null; retention_state: string; runtime_id: string; singleton_key?: string | null; state: string; tags: Array<string>; workdir_attachments?: Array<RuntimeWorkerWorkdirAttachmentSummary>; worker_id: string; workspace: WorkerWorkspaceSummary; };
 
 export type WorkerListResponse = { diagnostics?: Array<Diagnostic>; items: Array<WorkerSummary>; limit: number; source: string; workspace_id: string; };
 
@@ -67,7 +65,7 @@ export type WorkerState = { kind: "idle"; } | { kind: "busy"; state: WorkerBusyS
 
 export type WorkerStateSnapshot = { last_command_id: number; state: WorkerState; };
 
-export type WorkerSummary = { availability: SubscriptionWorkerAvailability; capabilities: WorkerCapabilitySummary; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
+export type WorkerSummary = { availability: SubscriptionWorkerAvailability; diagnostics?: Array<Diagnostic>; display_name?: string; host_id: string; implementation: WorkerImplementationSummary; label: string; last_seen_at?: string | null; pinned?: boolean; profile?: string | null; resource_key: string; retention_state?: string; runtime_id: string; singleton_key?: string | null; state: string; tags?: Array<string>; workdir_attachments?: Array<WorkerWorkdirAttachmentSummary>; worker_id: string; worker_state?: WorkerStateSnapshot | null; workspace: WorkerWorkspaceSummary; };
 
 export type WorkerWorkdirAttachmentSummary = { alias: string; effective_permissions: ExternalWorkdirPermissions; working_directory: WorkingDirectorySummary; };
 
diff --git a/web/workspace/src/lib/workspace/api/workers.test.ts b/web/workspace/src/lib/workspace/api/workers.test.ts
index 66b1bada0..c4ca9bdd3 100644
--- a/web/workspace/src/lib/workspace/api/workers.test.ts
+++ b/web/workspace/src/lib/workspace/api/workers.test.ts
@@ -56,13 +56,28 @@ const worker = {
     kind: "runtime",
     display_hint: "Runtime Worker",
   },
-  capabilities: {
-    can_stop: true,
-    can_spawn_followup: false,
-  },
   diagnostics: [],
 };
 
+Deno.test("Worker summaries omit the removed management capabilities field", () => {
+  const summary = { ...worker, resource_key: "W-1", availability: "observed" };
+  assertEquals("capabilities" in parseWorkerSummary(summary), false);
+  assertThrows(
+    () => parseWorkerSummary({ ...summary, capabilities: {} }),
+    Error,
+    "unknown field capabilities",
+  );
+  const created = parseBrowserCreateWorkerResponse({
+    workspace_id: "workspace-a",
+    runtime_id: "runtime-a",
+    worker_id: "worker-a",
+    console_href: "/w/workspace-a/workers/W-1/console",
+    worker,
+    diagnostics: [],
+  });
+  assertEquals("capabilities" in created.worker, false);
+});
+
 Deno.test("Worker summary parser enforces observation freshness", () => {
   const unavailable = {
     ...worker,
diff --git a/web/workspace/src/lib/workspace/api/workers.ts b/web/workspace/src/lib/workspace/api/workers.ts
index 96ac01d23..467a8030f 100644
--- a/web/workspace/src/lib/workspace/api/workers.ts
+++ b/web/workspace/src/lib/workspace/api/workers.ts
@@ -10,7 +10,6 @@ import type {
   RuntimeWorkerWorkdirAttachmentSummary,
   RuntimeWorkingDirectoryCleanupTarget,
   RuntimeWorkingDirectorySummary,
-  WorkerCapabilitySummary,
   WorkerImplementationSummary,
   WorkerLaunchOptionsResponse,
   WorkerLaunchProfileCandidate,
@@ -251,21 +250,6 @@ function implementationSummary(
   };
 }
 
-function capabilitySummary(
-  value: unknown,
-  label: string,
-): WorkerCapabilitySummary {
-  const item = record(value, label);
-  exact(item, ["can_stop", "can_spawn_followup"], label);
-  return {
-    can_stop: boolean(item.can_stop, `${label}.can_stop`),
-    can_spawn_followup: boolean(
-      item.can_spawn_followup,
-      `${label}.can_spawn_followup`,
-    ),
-  };
-}
-
 function workerStateSnapshot(
   value: unknown,
   label: string,
@@ -374,7 +358,6 @@ export function parseWorkerSummary(
       "pinned",
       "retention_state",
       "implementation",
-      "capabilities",
       "workdir_attachments",
       "diagnostics",
     ],
@@ -423,7 +406,6 @@ export function parseWorkerSummary(
       item.implementation,
       `${label}.implementation`,
     ),
-    capabilities: capabilitySummary(item.capabilities, `${label}.capabilities`),
     workdir_attachments: item.workdir_attachments === undefined
       ? undefined
       : array(
@@ -617,7 +599,6 @@ function workerSummary(
       "pinned",
       "retention_state",
       "implementation",
-      "capabilities",
       "workdir_attachments",
       "diagnostics",
     ],
@@ -641,7 +622,6 @@ function workerSummary(
       item.implementation,
       `${label}.implementation`,
     ),
-    capabilities: capabilitySummary(item.capabilities, `${label}.capabilities`),
     workdir_attachments: item.workdir_attachments === undefined
       ? undefined
       : array(
diff --git a/web/workspace/src/lib/workspace/sidebar/WorkersNavSection.svelte b/web/workspace/src/lib/workspace/sidebar/WorkersNavSection.svelte
index cfa355a68..c155c1985 100644
--- a/web/workspace/src/lib/workspace/sidebar/WorkersNavSection.svelte
+++ b/web/workspace/src/lib/workspace/sidebar/WorkersNavSection.svelte
@@ -3,6 +3,7 @@
   import { workerConsoleHref } from '$lib/workspace/resource-links';
   import { pushWorkspaceAlert } from '$lib/workspace/alerts/store';
   import {
+    canStopSidebarWorker,
     canDeleteSidebarWorker,
     deleteSidebarWorker,
     stopSidebarWorker,
@@ -91,14 +92,14 @@
   }
 
   async function stopWorker(worker: SidebarWorker) {
-    if (busyAction || !worker.capabilities.can_stop) return;
+    if (busyAction || !canStopSidebarWorker(worker)) return;
     closeWorkerMenu();
     busyAction = { workerKey: workerKey(worker), kind: 'stop' };
     try {
       await stopSidebarWorker(workspaceId, worker);
       workers = workers.map((item) =>
         workerKey(item) === workerKey(worker)
-          ? { ...item, state: 'stopped', capabilities: { ...item.capabilities, can_stop: false } }
+          ? { ...item, state: 'stopped', lifecycleState: 'stopped' }
           : item
       );
       pushWorkspaceAlert('info', `${worker.display_name || worker.label} stopped`, {
@@ -226,7 +227,7 @@
               <button
                 type="button"
                 role="menuitem"
-                disabled={busyAction !== null || !worker.capabilities.can_stop}
+                disabled={busyAction !== null || !canStopSidebarWorker(worker)}
                 onclick={() => stopWorker(worker)}
               >
                 {isBusy(worker, 'stop') ? 'Stopping…' : 'Stop'}
diff --git a/web/workspace/src/lib/workspace/sidebar/types.ts b/web/workspace/src/lib/workspace/sidebar/types.ts
index f1c7bf0c9..8e68ed3bf 100644
--- a/web/workspace/src/lib/workspace/sidebar/types.ts
+++ b/web/workspace/src/lib/workspace/sidebar/types.ts
@@ -10,7 +10,6 @@ import type {
   BrowserWorkerWorkingDirectorySelection
     as SharedBrowserWorkerWorkingDirectorySelection,
   Diagnostic as SharedDiagnostic,
-  WorkerCapabilitySummary as SharedWorkerCapabilitySummary,
   WorkerLaunchOptionsResponse as SharedWorkerLaunchOptionsResponse,
   WorkerLaunchProfileCandidate as SharedWorkerLaunchProfileCandidate,
   WorkerLaunchRuntimeOption as SharedWorkerLaunchRuntimeOption,
@@ -78,8 +77,6 @@ export type Runtime = {
   };
 };
 
-export type WorkerCapabilities = SharedWorkerCapabilitySummary;
-
 export type WorkerWorkdirAttachment = SharedWorkerWorkdirAttachmentSummary;
 
 export type Worker =
diff --git a/web/workspace/src/lib/workspace/sidebar/worker-actions.ts b/web/workspace/src/lib/workspace/sidebar/worker-actions.ts
index 3f3dcccf2..d49581628 100644
--- a/web/workspace/src/lib/workspace/sidebar/worker-actions.ts
+++ b/web/workspace/src/lib/workspace/sidebar/worker-actions.ts
@@ -4,10 +4,7 @@ import {
   parseRuntimeCleanupPlan,
   parseRuntimeWorkerLifecycleResult,
 } from "$lib/workspace/api/runtime-workers";
-import type {
-  Diagnostic,
-  Worker,
-} from "./types";
+import type { Diagnostic, Worker } from "./types";
 
 type FetchFn = typeof fetch;
 type WorkerActionTarget = Pick<Worker, "runtime_id" | "worker_id" | "state">;
@@ -25,13 +22,17 @@ async function responseError(response: Response): Promise<string> {
   const fallback = `${response.status} ${response.statusText}`.trim();
   try {
     const payload: unknown = await response.json();
-    if (typeof payload !== "object" || payload === null || Array.isArray(payload)) {
+    if (
+      typeof payload !== "object" || payload === null || Array.isArray(payload)
+    ) {
       return fallback;
     }
     const record = payload as Record<string, unknown>;
     if (typeof record.message === "string") return record.message.slice(0, 512);
     const nested = record.error;
-    if (typeof nested === "object" && nested !== null && !Array.isArray(nested)) {
+    if (
+      typeof nested === "object" && nested !== null && !Array.isArray(nested)
+    ) {
       const message = (nested as Record<string, unknown>).message;
       if (typeof message === "string") return message.slice(0, 512);
     }
@@ -51,6 +52,14 @@ function diagnosticMessage(
     fallback;
 }
 
+export function canStopSidebarWorker(worker: {
+  availability: Worker["availability"];
+  lifecycleState: string;
+}): boolean {
+  return worker.availability === "observed" &&
+    ["idle", "running", "paused"].includes(worker.lifecycleState);
+}
+
 export function canDeleteSidebarWorker(worker: WorkerActionTarget): boolean {
   return worker.state === "stopped";
 }
@@ -112,7 +121,9 @@ export async function deleteSidebarWorker(
     throw new Error(await responseError(executionResponse));
   }
 
-  const execution = parseRuntimeCleanupExecution(await executionResponse.json());
+  const execution = parseRuntimeCleanupExecution(
+    await executionResponse.json(),
+  );
   const outcome = execution.results.find((result) =>
     result.target_id === candidate.target_id
   );
diff --git a/web/workspace/src/lib/workspace/sidebar/worker-stop.browser.spec.ts b/web/workspace/src/lib/workspace/sidebar/worker-stop.browser.spec.ts
new file mode 100644
index 000000000..1ff7485aa
--- /dev/null
+++ b/web/workspace/src/lib/workspace/sidebar/worker-stop.browser.spec.ts
@@ -0,0 +1,136 @@
+// @vitest-environment happy-dom
+
+import {
+  cleanup,
+  fireEvent,
+  render,
+  screen,
+  waitFor,
+} from "@testing-library/svelte";
+import { afterEach, expect, test, vi } from "vitest";
+import type {
+  SubscriptionFrame,
+  SubscriptionWorker,
+} from "$lib/generated/protocol";
+import WorkersNavSection from "./WorkersNavSection.svelte";
+import { disposeWorkspaceWorkersStore } from "./worker-subscription";
+
+const transport = vi.hoisted(() => ({
+  listener: null as { onFrame(frame: SubscriptionFrame): void } | null,
+  close: vi.fn(),
+}));
+vi.mock("$lib/workspace/multiplexer", () => ({
+  workspaceMultiplexer: () => ({
+    subscribe: (
+      _selector: unknown,
+      listener: NonNullable<typeof transport.listener>,
+    ) => {
+      transport.listener = listener;
+      return { close: transport.close };
+    },
+  }),
+}));
+
+afterEach(() => {
+  cleanup();
+  disposeWorkspaceWorkersStore("stop-test");
+  transport.listener = null;
+  vi.unstubAllGlobals();
+});
+
+function snapshot(
+  state: SubscriptionWorker["state"],
+  availability: SubscriptionWorker["availability"],
+): SubscriptionFrame {
+  return {
+    protocol_version: 1,
+    frame: "response",
+    message: {
+      result: "subscribed",
+      payload: {
+        request_id: "request-1",
+        subscription_id: "subscription-1",
+        selector: { topic: "workspace_workers" },
+        snapshot_revision: 1,
+        snapshot: {
+          topic: "workers",
+          data: {
+            workers: [{
+              worker_id: "worker-a",
+              runtime_id: "runtime-a",
+              resource_key: "W-1",
+              availability,
+              subject_revision: 1,
+              state,
+              // An absent foreground snapshot must not prevent stopping an active catalog Worker.
+              worker_state: null,
+              has_running_internal_workers: false,
+              display_name: "Test worker",
+              workspace_id: "stop-test",
+              workdir_attachments: [],
+            }],
+          },
+        },
+      },
+    },
+  };
+}
+
+test.each(["idle", "running", "paused", "stopped"] as const)(
+  "Stop uses observed catalog state without capabilities (%s)",
+  async (state) => {
+    const request = vi.fn(async (input: RequestInfo | URL) =>
+      String(input).endsWith("/stop")
+        ? Response.json({
+          state: "accepted",
+          runtime_id: "runtime-a",
+          worker_id: "worker-a",
+          diagnostics: [],
+        })
+        : new Response(null, { status: 404 })
+    );
+    vi.stubGlobal("fetch", request);
+    render(WorkersNavSection, { workspaceId: "stop-test" });
+    await waitFor(() => expect(transport.listener).not.toBeNull());
+    transport.listener!.onFrame(snapshot(state, "observed"));
+    await fireEvent.click(
+      await screen.findByRole("button", { name: "Actions for Test worker" }),
+    );
+    const stop = screen.getByRole("menuitem", {
+      name: "Stop",
+    }) as HTMLButtonElement;
+    expect(stop.disabled).toBe(state === "stopped");
+    if (state === "stopped") return;
+    await fireEvent.click(stop);
+    await waitFor(() =>
+      expect(request.mock.calls.some(([url]) => String(url).endsWith("/stop")))
+        .toBe(true)
+    );
+    await fireEvent.click(
+      screen.getByRole("button", { name: "Actions for Test worker" }),
+    );
+    await waitFor(() =>
+      expect(
+        (screen.getByRole("menuitem", { name: "Stop" }) as HTMLButtonElement)
+          .disabled,
+      ).toBe(true)
+    );
+  },
+);
+
+test("Unavailable observation disables Stop even when catalog state is running", async () => {
+  vi.stubGlobal(
+    "fetch",
+    vi.fn(async () => new Response(null, { status: 404 })),
+  );
+  render(WorkersNavSection, { workspaceId: "stop-test" });
+  await waitFor(() => expect(transport.listener).not.toBeNull());
+  transport.listener!.onFrame(snapshot("running", "unavailable"));
+  await fireEvent.click(
+    await screen.findByRole("button", { name: "Actions for Test worker" }),
+  );
+  expect(
+    (screen.getByRole("menuitem", { name: "Stop" }) as HTMLButtonElement)
+      .disabled,
+  ).toBe(true);
+});
diff --git a/web/workspace/src/lib/workspace/sidebar/worker-subscription.ts b/web/workspace/src/lib/workspace/sidebar/worker-subscription.ts
index beb398bb6..8f957e9f2 100644
--- a/web/workspace/src/lib/workspace/sidebar/worker-subscription.ts
+++ b/web/workspace/src/lib/workspace/sidebar/worker-subscription.ts
@@ -16,6 +16,8 @@ import type { Worker } from "./types";
 export type SidebarWorker = Omit<Worker, "workdir_attachments"> & {
   workdir_attachments: SidebarWorkdirAttachment[];
   has_running_internal_workers: boolean;
+  /** Catalog lifecycle, independent of the possibly unknown foreground display state. */
+  lifecycleState: SubscriptionWorker["state"];
 };
 
 export type WorkspaceWorkersState = {
@@ -148,6 +150,7 @@ function projectWorker(
     },
     availability: worker.availability,
     state: liveWorkerState(worker),
+    lifecycleState: worker.state,
     worker_state: worker.worker_state,
     pinned: false,
     retention_state: "transient",
@@ -155,11 +158,6 @@ function projectWorker(
       kind: "runtime_subscription_worker",
       display_hint: "Workspace-authorized Runtime Worker",
     },
-    capabilities: {
-      can_stop: worker.availability !== "unavailable" &&
-        worker.state !== "stopped",
-      can_spawn_followup: false,
-    },
     workdir_attachments: (worker.workdir_attachments ?? []).map((
       attachment,
     ) => ({
diff --git a/web/workspace/src/lib/workspace/sidebar/workers.test.ts b/web/workspace/src/lib/workspace/sidebar/workers.test.ts
index 241490a24..13020c01e 100644
--- a/web/workspace/src/lib/workspace/sidebar/workers.test.ts
+++ b/web/workspace/src/lib/workspace/sidebar/workers.test.ts
@@ -38,10 +38,6 @@ function worker(overrides: Partial<Worker>): Worker {
       kind: "runtime_worker",
       display_hint: "Runtime Worker",
     },
-    capabilities: {
-      can_stop: true,
-      can_spawn_followup: false,
-    },
     workdir_attachments: [],
     diagnostics: [],
     ...overrides,
@@ -56,10 +52,6 @@ Deno.test("registry-only workers are not sidebar targets or console targets", ()
       kind: "backend_worker_registry",
       display_hint: "Missing Worker",
     },
-    capabilities: {
-      can_stop: false,
-      can_spawn_followup: false,
-    },
   });
   assertEquals(canShowWorkerInSidebar(registryOnly), false);
   assertEquals(canOpenWorkerConsole(registryOnly), false);
diff --git a/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/+page.svelte b/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/+page.svelte
index 3cb6019b1..42cc831e6 100644
--- a/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/+page.svelte
+++ b/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/+page.svelte
@@ -1935,22 +1935,6 @@
                         </dd>
                     </div>
                 </dl>
-                <details class="metadata-details">
-                    <summary>Capabilities</summary>
-                    <ul>
-                        <li>
-                            stop: {worker.capabilities.can_stop
-                                ? "available"
-                                : "unsupported"}
-                        </li>
-                        <li>
-                            follow-up spawn: {worker.capabilities
-                                .can_spawn_followup
-                                ? "available"
-                                : "unsupported"}
-                        </li>
-                    </ul>
-                </details>
             {:else if !workerError}
                 <p>Loading Worker detail…</p>
             {/if}
diff --git a/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/console-display.browser.spec.ts b/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/console-display.browser.spec.ts
index bebe3c044..11ac32c05 100644
--- a/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/console-display.browser.spec.ts
+++ b/web/workspace/src/routes/w/[workspaceId]/workers/[workerRef]/console/console-display.browser.spec.ts
@@ -62,10 +62,6 @@ function worker(workerId = "worker-a", runtimeId = "runtime-a"): Worker {
     profile: "default",
     tags: [],
     diagnostics: [],
-    capabilities: {
-      can_stop: true,
-      can_spawn_followup: true,
-    },
     workspace: { visibility: "workspace", identity: "workspace-a" },
     implementation: { kind: "builtin", display_hint: "test" },
     workdir_attachments: [],
diff --git a/web/workspace/test/sidebar/worker-actions.test.ts b/web/workspace/test/sidebar/worker-actions.test.ts
index c6435cdd8..5f54d0ca3 100644
--- a/web/workspace/test/sidebar/worker-actions.test.ts
+++ b/web/workspace/test/sidebar/worker-actions.test.ts
@@ -1,5 +1,6 @@
 import {
   canDeleteSidebarWorker,
+  canStopSidebarWorker,
   deleteSidebarWorker,
   stopSidebarWorker,
 } from "../../src/lib/workspace/sidebar/worker-actions.ts";
@@ -41,7 +42,6 @@ const worker = {
   runtime_id: "runtime /",
   worker_id: "worker /",
   state: "running",
-  capabilities: { can_stop: true },
 } as Worker;
 
 function jsonResponse(payload: unknown, status = 200): Response {
@@ -51,6 +51,33 @@ function jsonResponse(payload: unknown, status = 200): Response {
   });
 }
 
+Deno.test("sidebar Stop follows observed catalog lifecycle, not foreground display state", () => {
+  for (const lifecycleState of ["idle", "running", "paused"]) {
+    const target = {
+      availability: "observed" as const,
+      lifecycleState,
+      state: "unknown",
+    };
+    assert(canStopSidebarWorker(target));
+    assert(!canStopSidebarWorker({ ...target, availability: "unavailable" }));
+  }
+  for (
+    const lifecycleState of [
+      "stopped",
+      "missing",
+      "execution_unavailable",
+      "unknown",
+    ]
+  ) {
+    const target = {
+      availability: "observed" as const,
+      lifecycleState,
+      state: "running",
+    };
+    assert(!canStopSidebarWorker(target));
+  }
+});
+
 Deno.test("sidebar Stop uses the workspace-scoped Worker lifecycle endpoint", async () => {
   const requests: Array<{ url: string; init?: RequestInit }> = [];
   const fetchFn = (async (input: RequestInfo | URL, init?: RequestInit) => {