fix: reconcile T-697 generated contracts with latest develop

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 (sha256:4dc4cdeb9c6f3830b9797af0dc286a1baa6b07d9ed0bf1e576712cd155582ece)
+// Input contract: 0.1.0 (sha256:f09c555159412f3e5ec7328317cc99b9d3916f6e8b9d78235f16a6b3f7e2eab0)
 // 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/memory-api.ts

@@ -9,6 +9,10 @@ export const MEMORY_API_LIMITS = {
   maxIdentifierBytes: 512,
 } as const;
 
+export const SUBJEKTIV_API_LIMITS = {
+  maxBehaviorBytes: 16384,
+} as const;
+
 export type DiagnosticSeverity = "info" | "warning" | "error";
 
 export type Diagnostic = { code: string, severity: DiagnosticSeverity, message: string, };
@@ -35,9 +39,11 @@ export type MemoryStagingListResponse = { limit: number, returned_count: number,
 
 export type SubjektivSubjectState = "active" | "retired";
 
-export type SubjektivSubjectCreateRequest = { role: string, };
+export type SubjektivSubjectCreateRequest = { role: string, behavior_md?: string, };
 
-export type SubjektivSubjectResponse = { id: string, role: string, state: SubjektivSubjectState, store_revision: number, created_at: string, updated_at: string, current_worker?: | import("./worker-launch-api").WorkerLaunchWorkerSummary | null, };
+export type SubjektivSubjectBehaviorUpdateRequest = { expected_behavior_revision: number, behavior_md: string, };
+
+export type SubjektivSubjectResponse = { id: string, role: string, behavior_md: string, behavior_revision: number, state: SubjektivSubjectState, store_revision: number, created_at: string, updated_at: string, current_worker?: | import("./worker-launch-api").WorkerLaunchWorkerSummary | null, };
 
 export type SubjektivSubjectListResponse = { limit: number, items: Array<SubjektivSubjectResponse>, next_cursor?: string | null, has_more: boolean, };
 

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 (sha256:4dc4cdeb9c6f3830b9797af0dc286a1baa6b07d9ed0bf1e576712cd155582ece)
+// Input contract: 0.1.0 (sha256:f09c555159412f3e5ec7328317cc99b9d3916f6e8b9d78235f16a6b3f7e2eab0)
 // 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 (sha256:4dc4cdeb9c6f3830b9797af0dc286a1baa6b07d9ed0bf1e576712cd155582ece)
+// Input contract: 0.1.0 (sha256:f09c555159412f3e5ec7328317cc99b9d3916f6e8b9d78235f16a6b3f7e2eab0)
 // 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 (sha256:4dc4cdeb9c6f3830b9797af0dc286a1baa6b07d9ed0bf1e576712cd155582ece)
+// Input contract: 0.1.0 (sha256:f09c555159412f3e5ec7328317cc99b9d3916f6e8b9d78235f16a6b3f7e2eab0)
 // 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 (sha256:4dc4cdeb9c6f3830b9797af0dc286a1baa6b07d9ed0bf1e576712cd155582ece)
+// Input contract: 0.1.0 (sha256:f09c555159412f3e5ec7328317cc99b9d3916f6e8b9d78235f16a6b3f7e2eab0)
 // 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 (sha256:4dc4cdeb9c6f3830b9797af0dc286a1baa6b07d9ed0bf1e576712cd155582ece)
+// Input contract: 0.1.0 (sha256:f09c555159412f3e5ec7328317cc99b9d3916f6e8b9d78235f16a6b3f7e2eab0)
 // 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/memory/api.ts

@@ -1,4 +1,7 @@
-import { MEMORY_API_LIMITS } from "#lib/generated/memory-api.ts";
+import {
+  MEMORY_API_LIMITS,
+  SUBJEKTIV_API_LIMITS,
+} from "#lib/generated/memory-api.ts";
 import { readBoundedJson, workspaceApiPath } from "#lib/workspace/api/http.ts";
 import type {
   Diagnostic,
@@ -26,6 +29,7 @@ import type {
   SubjektivResidentSurfaceAvailability,
   SubjektivResidentSurfaceResponse,
   SubjektivResidentSurfaceSnapshot,
+  SubjektivSubjectBehaviorUpdateRequest,
   SubjektivSubjectCreateRequest,
   SubjektivSubjectListResponse,
   SubjektivSubjectResponse,
@@ -84,6 +88,7 @@ export const MEMORY_API_LOAD_POLICY = {
 } as const;
 
 const MAX_SUBJECT_ROLE_BYTES = 256;
+export const MAX_SUBJECT_BEHAVIOR_BYTES = SUBJEKTIV_API_LIMITS.maxBehaviorBytes;
 const MAX_SUBJECT_CREATE_ERROR_BYTES = 1024 * 1024;
 
 export type SubjektivSubjectCreateErrorKind =
@@ -126,7 +131,31 @@ export function validateSubjektivSubjectCreateRequest(
       "Subject role must be at most 256 bytes and contain no control characters.",
     );
   }
-  return { role: request.role };
+  const behaviorMd = request.behavior_md ?? "";
+  validateSubjectBehavior(behaviorMd);
+  return { role: request.role, behavior_md: behaviorMd };
+}
+
+function validateSubjectBehavior(behaviorMd: string): void {
+  const bytes = new TextEncoder().encode(behaviorMd).byteLength;
+  if (bytes > MAX_SUBJECT_BEHAVIOR_BYTES) {
+    throw new SubjektivSubjectCreateError(
+      "validation",
+      `Subject behavior must be at most ${MAX_SUBJECT_BEHAVIOR_BYTES} bytes.`,
+    );
+  }
+  if (behaviorMd.length > 0 && behaviorMd.trim().length === 0) {
+    throw new SubjektivSubjectCreateError(
+      "validation",
+      "Subject behavior must be empty or contain non-whitespace text.",
+    );
+  }
+  if (/[\u0000-\u0008\u000B\u000C\u000E-\u001F\u007F]/u.test(behaviorMd)) {
+    throw new SubjektivSubjectCreateError(
+      "validation",
+      "Subject behavior contains an unsupported control character.",
+    );
+  }
 }
 
 export async function createSubjektivSubject(
@@ -170,8 +199,11 @@ export async function createSubjektivSubject(
     const subject = parseSubjektivSubjectResponse(
       await readBoundedJson(response, MEMORY_API_LIMITS.maxResponseBytes),
     );
-    if (subject.role !== validated.role) {
-      throw new Error("created Subject role does not match the request");
+    if (
+      subject.role !== validated.role ||
+      subject.behavior_md !== validated.behavior_md
+    ) {
+      throw new Error("created Subject does not match the request");
     }
     return subject;
   } catch {
@@ -182,6 +214,68 @@ export async function createSubjektivSubject(
   }
 }
 
+export async function updateSubjektivSubjectBehavior(
+  fetchFn: typeof fetch,
+  workspaceId: string,
+  subjectId: string,
+  request: SubjektivSubjectBehaviorUpdateRequest,
+): Promise<SubjektivSubjectResponse> {
+  validateSubjectBehavior(request.behavior_md);
+  if (
+    !Number.isSafeInteger(request.expected_behavior_revision) ||
+    request.expected_behavior_revision < 0
+  ) {
+    throw new SubjektivSubjectCreateError(
+      "validation",
+      "Subject behavior revision is invalid.",
+    );
+  }
+  let response: Response;
+  try {
+    response = await fetchFn(
+      workspaceApiPath(
+        workspaceId,
+        `/subjektiv/subjects/${encodeURIComponent(subjectId)}/behavior`,
+      ),
+      {
+        method: "PATCH",
+        headers: { "content-type": "application/json" },
+        body: JSON.stringify(request),
+      },
+    );
+  } catch {
+    throw new SubjektivSubjectCreateError(
+      "unknown_outcome",
+      "The save outcome is unknown. Reload the Subject before retrying.",
+    );
+  }
+  if (!response.ok) {
+    const message = await subjektivSubjectCreateErrorMessage(response);
+    throw new SubjektivSubjectCreateError(
+      response.status >= 500 ? "unknown_outcome" : "rejected",
+      response.status === 409
+        ? "The behavior changed elsewhere. Reload the Subject and review the latest text."
+        : message,
+      response.status,
+    );
+  }
+  try {
+    const subject = parseSubjektivSubjectResponse(
+      await readBoundedJson(response, MEMORY_API_LIMITS.maxResponseBytes),
+      subjectId,
+    );
+    if (subject.behavior_md !== request.behavior_md) {
+      throw new Error("saved Subject behavior does not match the request");
+    }
+    return subject;
+  } catch {
+    throw new SubjektivSubjectCreateError(
+      "unknown_outcome",
+      "The behavior may have been saved, but the response could not be confirmed. Reload the Subject.",
+    );
+  }
+}
+
 async function subjektivSubjectCreateErrorMessage(
   response: Response,
 ): Promise<string> {
@@ -202,7 +296,7 @@ async function subjektivSubjectCreateErrorMessage(
   } catch {
     // A rejected request still has a known outcome even when its body is invalid.
   }
-  return `Subject creation failed with HTTP ${response.status}.`;
+  return `Subject request failed with HTTP ${response.status}.`;
 }
 
 export function parseMemoryDocumentResponse(
@@ -454,6 +548,8 @@ export function parseSubjektivSubjectResponse(
     [
       "id",
       "role",
+      "behavior_md",
+      "behavior_revision",
       "state",
       "store_revision",
       "created_at",
@@ -472,6 +568,12 @@ export function parseSubjektivSubjectResponse(
   const result: SubjektivSubjectResponse = {
     id,
     role: requiredString(record, "role"),
+    behavior_md: requiredString(
+      record,
+      "behavior_md",
+      MAX_SUBJECT_BEHAVIOR_BYTES,
+    ),
+    behavior_revision: requiredNonNegativeInteger(record, "behavior_revision"),
     state,
     store_revision: requiredNonNegativeInteger(record, "store_revision"),
     created_at: requiredString(record, "created_at"),

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

@@ -14,13 +14,16 @@
   const subjects = $derived(data.subjects.data?.items ?? []);
   let createExpanded = $state(false);
   let role = $state('');
+  let behaviorMd = $state('');
   let submitting = $state(false);
   let createError = $state<string | null>(null);
   let roleInvalid = $state(false);
+  let behaviorInvalid = $state(false);
   let createOutcomeUnknown = $state(false);
   let createdSubject = $state<SubjektivSubjectResponse | null>(null);
   let createButton = $state<HTMLButtonElement>();
   let roleInput = $state<HTMLInputElement>();
+  let behaviorInput = $state<HTMLTextAreaElement>();
 
   function subjectHref(subjectId: string): string {
     return workspaceRoute(data.workspaceId, `/memory/${encodeURIComponent(subjectId)}`);
@@ -39,6 +42,7 @@
     createExpanded = true;
     createError = null;
     roleInvalid = false;
+    behaviorInvalid = false;
     createOutcomeUnknown = false;
     createdSubject = null;
     await tick();
@@ -49,8 +53,10 @@
     if (submitting) return;
     createExpanded = false;
     role = '';
+    behaviorMd = '';
     createError = null;
     roleInvalid = false;
+    behaviorInvalid = false;
     createOutcomeUnknown = false;
     createdSubject = null;
     await tick();
@@ -62,9 +68,13 @@
     submitting = true;
     createError = null;
     roleInvalid = false;
+    behaviorInvalid = false;
     createOutcomeUnknown = false;
     try {
-      const subject = await createSubjektivSubject(fetch, data.workspaceId, { role });
+      const subject = await createSubjektivSubject(fetch, data.workspaceId, {
+        role,
+        behavior_md: behaviorMd,
+      });
       createdSubject = subject;
       try {
         await goto(subjectHref(subject.id));
@@ -73,14 +83,16 @@
       }
     } catch (error) {
       if (error instanceof SubjektivSubjectCreateError) {
-        roleInvalid = error.kind === 'validation';
+        roleInvalid = error.kind === 'validation' && error.message.startsWith('Subject role');
+        behaviorInvalid = error.kind === 'validation' && error.message.startsWith('Subject behavior');
         createOutcomeUnknown = error.kind === 'unknown_outcome';
         createError = error.status === 401 || error.status === 403
           ? 'You do not have permission to create Subjects in this Workspace.'
           : error.message;
-        if (roleInvalid) {
+        if (roleInvalid || behaviorInvalid) {
           await tick();
-          roleInput?.focus();
+          if (behaviorInvalid) behaviorInput?.focus();
+          else roleInput?.focus();
         }
       } else {
         createOutcomeUnknown = true;
@@ -149,9 +161,22 @@
           disabled={submitting || createdSubject !== null}
           onkeydown={createFormKeydown}
           aria-invalid={roleInvalid ? 'true' : undefined}
-          aria-describedby={createError ? 'subject-role-help subject-create-error' : 'subject-role-help'}
+          aria-describedby={createError && roleInvalid ? 'subject-role-help subject-create-error' : 'subject-role-help'}
         />
       </label>
+      <label class="subject-role-field">
+        <span>Behavior <small>Optional, user-managed</small></span>
+        <textarea
+          bind:this={behaviorInput}
+          bind:value={behaviorMd}
+          rows="7"
+          disabled={submitting || createdSubject !== null}
+          onkeydown={createFormKeydown}
+          aria-invalid={behaviorInvalid ? 'true' : undefined}
+          aria-describedby={createError && behaviorInvalid ? 'subject-behavior-help subject-create-error' : 'subject-behavior-help'}
+        ></textarea>
+        <small id="subject-behavior-help">Persistent guidance injected verbatim for this Subject. It remains separate from generated Memory and can be edited later.</small>
+      </label>
       {#if createError}
         <div
           id="subject-create-error"
@@ -318,20 +343,25 @@
   }
 
   .subject-create-actions {
-    grid-column: 3;
-    grid-row: 1;
+    grid-column: 2;
   }
 
   .subject-create-panel {
     display: grid;
-    grid-template-columns: minmax(14rem, 0.8fr) minmax(18rem, 1fr) auto;
-    align-items: end;
+    grid-template-columns: minmax(14rem, 0.7fr) minmax(18rem, 1.3fr);
+    align-items: start;
     gap: var(--space-4);
     padding: var(--space-4);
     background: var(--bg-raised);
     border-radius: var(--radius-soft);
   }
 
+  .subject-create-copy {
+    grid-column: 1;
+    grid-row: 1 / span 4;
+    align-self: start;
+  }
+
   .subject-create-copy h2,
   .subject-create-copy p,
   .subject-create-error p {
@@ -353,7 +383,8 @@
     font-weight: 700;
   }
 
-  .subject-role-field input {
+  .subject-role-field input,
+  .subject-role-field textarea {
     width: 100%;
     min-width: 0;
     border: 1px solid var(--line);
@@ -363,7 +394,15 @@
     color: var(--text-strong);
   }
 
-  .subject-role-field input[aria-invalid='true'] {
+  .subject-role-field textarea {
+    min-height: 8rem;
+    resize: vertical;
+    font: inherit;
+    line-height: 1.5;
+  }
+
+  .subject-role-field input[aria-invalid='true'],
+  .subject-role-field textarea[aria-invalid='true'] {
     border-color: var(--danger);
   }
 
@@ -496,6 +535,7 @@
       align-items: stretch;
     }
 
+    .subject-create-copy,
     .subject-create-error,
     .subject-create-actions {
       grid-column: 1;

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

@@ -1,14 +1,91 @@
 <script lang="ts">
+  import { untrack } from 'svelte';
   import DocumentMarkdown from '#lib/workspace/markdown/DocumentMarkdown.svelte';
   import { formatDate, workspaceRoute } from '#lib/workspace/api/http.ts';
-  import type {
-    SubjektivMemoryState,
-    SubjektivResidentSurfaceAvailability,
-  } from '#lib/generated/memory-api.ts';
+  import {
+    SubjektivSubjectCreateError,
+    updateSubjektivSubjectBehavior,
+  } from '#lib/workspace/memory/api.ts';
+  import type { SubjektivMemoryState, SubjektivResidentSurfaceAvailability } from '#lib/generated/memory-api.ts';
   import type { PageProps } from './$types';
 
   let { data }: PageProps = $props();
 
+  let subject = $state(untrack(() => data.subject.data));
+  let editingBehavior = $state(false);
+  let behaviorDraft = $state(untrack(() => subject?.behavior_md ?? ''));
+  let behaviorSaving = $state(false);
+  let behaviorError = $state<string | null>(null);
+  let behaviorSaveConfirmed = $state(false);
+
+  let routeGeneration = 0;
+  let subjectWorkspaceId = untrack(() => data.workspaceId);
+
+  // SvelteKit reuses this page across Subject and Workspace routes. A new
+  // loader snapshot owns a new editor and fences all previous mutations.
+  $effect(() => {
+    const workspaceId = data.workspaceId;
+    const subjectId = data.subjectId;
+    const loadedSubject = data.subject.data;
+    untrack(() => {
+      routeGeneration += 1;
+      subjectWorkspaceId = workspaceId;
+      subject = loadedSubject?.id === subjectId ? loadedSubject : null;
+      behaviorDraft = subject?.behavior_md ?? '';
+      editingBehavior = false;
+      behaviorSaving = false;
+      behaviorError = null;
+      behaviorSaveConfirmed = false;
+    });
+  });
+
+  async function saveBehavior(): Promise<void> {
+    if (!subject || behaviorSaving || subject.id !== data.subjectId || subjectWorkspaceId !== data.workspaceId) return;
+    const generation = routeGeneration;
+    const workspaceId = subjectWorkspaceId;
+    const subjectId = subject.id;
+    const request = {
+      expected_behavior_revision: subject.behavior_revision,
+      behavior_md: behaviorDraft,
+    };
+    const isCurrent = () => generation === routeGeneration &&
+      data.workspaceId === workspaceId && data.subjectId === subjectId;
+    behaviorSaving = true;
+    behaviorError = null;
+    behaviorSaveConfirmed = false;
+    try {
+      const updated = await updateSubjektivSubjectBehavior(fetch, workspaceId, subjectId, request);
+      if (!isCurrent()) return;
+      subject = updated;
+      behaviorDraft = updated.behavior_md;
+      editingBehavior = false;
+      behaviorSaveConfirmed = true;
+    } catch (error) {
+      if (!isCurrent()) return;
+      behaviorError = error instanceof SubjektivSubjectCreateError
+        ? (error.status === 401 || error.status === 403
+          ? 'You do not have permission to edit this Subject.'
+          : error.message)
+        : 'The save outcome is unknown. Reload the Subject before retrying.';
+    } finally {
+      if (isCurrent()) behaviorSaving = false;
+    }
+  }
+
+  function beginBehaviorEdit(): void {
+    if (!subject) return;
+    behaviorDraft = subject.behavior_md;
+    behaviorError = null;
+    behaviorSaveConfirmed = false;
+    editingBehavior = true;
+  }
+
+  function cancelBehaviorEdit(): void {
+    behaviorDraft = subject?.behavior_md ?? '';
+    behaviorError = null;
+    editingBehavior = false;
+  }
+
   const surface = $derived(data.surface.data);
   const snapshot = $derived(surface?.snapshot ?? null);
   const memories = $derived(data.memories.data?.items ?? []);
@@ -51,7 +128,7 @@
     if (availability !== 'ready') return 'No current generated context is available to use.';
     return snapshot?.body_md.trim()
       ? 'Current generated context is available.'
-      : 'A current empty surface exists; there is no resident context to show.';
+      : 'A current empty surface exists; there is no generated Memory context to show.';
   }
 
   function subjectStateLabel(state: 'active' | 'retired'): string {
@@ -60,7 +137,7 @@
 </script>
 
 <svelte:head>
-  <title>{data.subject.data?.role ?? data.subjectId} · Memory · Yoi Workspace</title>
+  <title>{subject?.role ?? data.subjectId} · Memory · Yoi Workspace</title>
   <meta name="description" content="Subject resident surface and current committed Memories" />
 </svelte:head>
 
@@ -70,23 +147,23 @@
   <header class="memory-page-header">
     <div>
       <p class="memory-eyebrow">Memory subject</p>
-      <h1 id="subject-heading">{data.subject.data?.role ?? data.subjectId}</h1>
+      <h1 id="subject-heading">{subject?.role ?? data.subjectId}</h1>
       <code class="subject-id" title={data.subjectId}>{data.subjectId}</code>
     </div>
-    <span class="read-only-label">Read-only</span>
+    <span class="read-only-label">Behavior editable</span>
   </header>
 
-  {#if data.subject.data}
+  {#if subject}
     <section class="subject-overview" aria-label="Subject status">
       <div>
         <span>Subject status</span>
-        <strong class="subject-state is-{data.subject.data.state}">{subjectStateLabel(data.subject.data.state)}</strong>
-        <p>{data.subject.data.state === 'active' ? 'Available for new Worker connections.' : 'No longer available for new Worker connections.'}</p>
+        <strong class="subject-state is-{subject.state}">{subjectStateLabel(subject.state)}</strong>
+        <p>{subject.state === 'active' ? 'Available for new Worker connections.' : 'No longer available for new Worker connections.'}</p>
       </div>
       <div>
         <span>Worker connection</span>
-        <strong>{data.subject.data.current_worker ? 'Connected' : 'Not connected'}</strong>
-        <p>{data.subject.data.current_worker?.display_name ?? 'No Worker currently owns this Subject connection.'}</p>
+        <strong>{subject.current_worker ? 'Connected' : 'Not connected'}</strong>
+        <p>{subject.current_worker?.display_name ?? 'No Worker currently owns this Subject connection.'}</p>
       </div>
       <div>
         <span>Committed Memories</span>
@@ -99,7 +176,7 @@
         {/if}
       </div>
       <div>
-        <span>Resident context</span>
+        <span>Generated Memory context</span>
         {#if surface}
           <strong class="availability is-{surface.availability}">{surfaceLabel(surface.availability)}</strong>
           <p>{surfaceSummary(surface.availability)}</p>
@@ -113,12 +190,12 @@
     <details class="subject-technical-details">
       <summary>Technical details</summary>
       <dl>
-        <div><dt>Subject ID</dt><dd><code>{data.subject.data.id}</code></dd></div>
+        <div><dt>Subject ID</dt><dd><code>{subject.id}</code></dd></div>
         <div>
           <dt>Subject store revision</dt>
-          <dd>{data.subject.data.store_revision}<small>Internal change number for committed Memories; not a Memory count or content-quality score.</small></dd>
+          <dd>{subject.store_revision}<small>Internal change number for committed Memories; not a Memory count or content-quality score.</small></dd>
         </div>
-        <div><dt>Last changed</dt><dd><time datetime={data.subject.data.updated_at}>{formatDate(data.subject.data.updated_at)}</time></dd></div>
+        <div><dt>Last changed</dt><dd><time datetime={subject.updated_at}>{formatDate(subject.updated_at)}</time></dd></div>
       </dl>
     </details>
   {:else if data.subject.error}
@@ -130,6 +207,40 @@
     <div class="memory-state" role="status"><p>Subject details are unavailable.</p></div>
   {/if}
 
+  {#if subject}
+    <section class="behavior-section" aria-labelledby="subject-behavior-heading">
+      <header class="section-heading">
+        <div>
+          <p class="memory-eyebrow">User-managed context</p>
+          <h2 id="subject-behavior-heading">Behavior</h2>
+        </div>
+        {#if !editingBehavior}
+          <button type="button" class="behavior-edit" onclick={beginBehaviorEdit}>Edit</button>
+        {/if}
+      </header>
+      <p class="behavior-help">The Host injects this text verbatim for connected Workers, separately from generated Memory. Saving confirms storage only. Connected Workers check for the latest revision before later model requests; this page does not report that application.</p>
+      {#if editingBehavior}
+        <form class="behavior-form" aria-busy={behaviorSaving} onsubmit={(event) => { event.preventDefault(); void saveBehavior(); }}>
+          <label>
+            <span class="sr-only">Subject behavior</span>
+            <textarea bind:value={behaviorDraft} rows="9" disabled={behaviorSaving} aria-invalid={behaviorError ? 'true' : undefined} aria-describedby={behaviorError ? 'subject-behavior-edit-error' : undefined}></textarea>
+          </label>
+          {#if behaviorError}<p id="subject-behavior-edit-error" class="behavior-error" role="alert">{behaviorError}</p>{/if}
+          <div class="behavior-actions">
+            <button type="submit" disabled={behaviorSaving}>{behaviorSaving ? 'Saving…' : 'Save behavior'}</button>
+            <button type="button" disabled={behaviorSaving} onclick={cancelBehaviorEdit}>Cancel</button>
+            <button type="button" disabled={behaviorSaving || behaviorDraft.length === 0} onclick={() => { behaviorDraft = ''; }}>Clear</button>
+          </div>
+        </form>
+      {:else if subject.behavior_md.length > 0}
+        <article class="behavior-document" aria-label="User-managed Subject behavior"><pre>{subject.behavior_md}</pre></article>
+      {:else}
+        <div class="memory-state" role="status"><strong>No behavior is set.</strong><p>Connected Workers receive an explicit empty behavior document.</p></div>
+      {/if}
+      {#if behaviorSaveConfirmed}<p class="behavior-saved" role="status">Behavior storage confirmed at revision {subject.behavior_revision}. This page does not confirm application by a connected Worker.</p>{/if}
+    </section>
+  {/if}
+
   <section class="surface-section" aria-labelledby="resident-surface-heading">
     <header class="section-heading">
       <div>
@@ -434,6 +545,7 @@
     color: var(--danger);
   }
 
+  .behavior-section,
   .surface-section,
   .memories-section {
     display: grid;
@@ -442,6 +554,78 @@
     padding-top: var(--space-3);
   }
 
+  .behavior-help,
+  .behavior-saved,
+  .behavior-error {
+    margin: 0;
+    color: var(--text-muted);
+    font-size: var(--font-size-compact);
+  }
+
+  .behavior-error { color: var(--danger); }
+  .behavior-saved { color: var(--success); }
+
+  .behavior-form,
+  .behavior-form label {
+    display: grid;
+    gap: var(--space-3);
+  }
+
+  .behavior-form textarea {
+    width: 100%;
+    min-height: 10rem;
+    padding: var(--space-3);
+    color: var(--text);
+    background: var(--surface-raised);
+    border: 1px solid var(--line-strong);
+    border-radius: var(--radius-sm);
+    font: inherit;
+    line-height: 1.5;
+    resize: vertical;
+  }
+
+  .behavior-actions {
+    display: flex;
+    flex-wrap: wrap;
+    gap: var(--space-2);
+  }
+
+  .behavior-edit,
+  .behavior-actions button {
+    padding: var(--space-2) var(--space-3);
+    color: var(--text);
+    background: var(--surface-raised);
+    border: 1px solid var(--line-strong);
+    border-radius: var(--radius-sm);
+    cursor: pointer;
+  }
+
+  .behavior-actions button:disabled { cursor: not-allowed; opacity: 0.55; }
+
+  .behavior-document pre {
+    margin: 0;
+    padding: var(--space-4);
+    overflow-wrap: anywhere;
+    white-space: pre-wrap;
+    background: var(--surface-raised);
+    border: 1px solid var(--line);
+    border-radius: var(--radius-sm);
+    font: inherit;
+    line-height: 1.6;
+  }
+
+  .sr-only {
+    position: absolute;
+    width: 1px;
+    height: 1px;
+    padding: 0;
+    margin: -1px;
+    overflow: hidden;
+    clip: rect(0, 0, 0, 0);
+    white-space: nowrap;
+    border: 0;
+  }
+
   .surface-meta,
   .pill-row {
     display: flex;

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

@@ -34,6 +34,8 @@ function subject() {
   return {
     id: "subject-1",
     role: "Release coordinator",
+    behavior_md: "Prefer explicit evidence.",
+    behavior_revision: 2,
     state: "active" as const,
     store_revision: 9,
     created_at: "2026-01-01T00:00:00Z",
@@ -99,6 +101,12 @@ test("creates one Subject with the exact role and navigates to its generated det
   }) as HTMLInputElement;
   await waitFor(() => expect(document.activeElement).toBe(roleInput));
   await fireEvent.input(roleInput, { target: { value: "  Review lead  " } });
+  const behaviorInput = screen.getByRole("textbox", {
+    name: /Behavior/,
+  }) as HTMLTextAreaElement;
+  await fireEvent.input(behaviorInput, {
+    target: { value: "Challenge unsupported assumptions." },
+  });
 
   const submit = screen.getByRole("button", { name: "Create Subject" });
   await fireEvent.click(submit);
@@ -113,6 +121,8 @@ test("creates one Subject with the exact role and navigates to its generated det
   resolveRequest(Response.json({
     id: "generated-subject-1",
     role: "  Review lead  ",
+    behavior_md: "Challenge unsupported assumptions.",
+    behavior_revision: 0,
     state: "active",
     store_revision: 0,
     created_at: "2026-01-03T00:00:00Z",
@@ -130,7 +140,9 @@ test("creates one Subject with the exact role and navigates to its generated det
   ];
   expect(path).toBe("/api/w/workspace-1/subjektiv/subjects");
   expect(init.method).toBe("POST");
-  expect(init.body).toBe('{"role":"  Review lead  "}');
+  expect(init.body).toBe(
+    '{"role":"  Review lead  ","behavior_md":"Challenge unsupported assumptions."}',
+  );
 });
 
 test("keeps creation available for an empty list and restores focus on cancel", async () => {
@@ -149,7 +161,7 @@ test("keeps creation available for an empty list and restores focus on cancel",
   expect(screen.queryByRole("textbox", { name: "Role" })).toBeNull();
 });
 
-test("preserves invalid and rejected role drafts with accessible errors", async () => {
+test("preserves invalid and rejected Subject drafts with accessible field errors", async () => {
   const fetchMock = vi.fn(() =>
     Promise.resolve(Response.json(
       {
@@ -175,6 +187,20 @@ test("preserves invalid and rejected role drafts with accessible errors", async
   expect(fetchMock).not.toHaveBeenCalled();
 
   await fireEvent.input(input, { target: { value: "Release reviewer" } });
+  const behaviorInput = screen.getByRole("textbox", {
+    name: /Behavior/,
+  }) as HTMLTextAreaElement;
+  await fireEvent.input(behaviorInput, { target: { value: "   " } });
+  await fireEvent.click(screen.getByRole("button", { name: "Create Subject" }));
+  expect(screen.getByRole("alert").textContent).toContain(
+    "empty or contain non-whitespace",
+  );
+  expect(behaviorInput.getAttribute("aria-invalid")).toBe("true");
+  expect(fetchMock).not.toHaveBeenCalled();
+
+  await fireEvent.input(behaviorInput, {
+    target: { value: "Challenge unsupported assumptions." },
+  });
   await fireEvent.click(screen.getByRole("button", { name: "Create Subject" }));
   await waitFor(() => {
     expect(screen.getByRole("alert").textContent).toContain(
@@ -273,6 +299,11 @@ test("renders a ready resident surface and committed Memory lifecycle states", a
     expect(screen.getByRole("heading", { name: "Resident context", level: 1 }))
       .not.toBeNull();
   });
+  expect(
+    screen.getByRole("article", { name: "User-managed Subject behavior" })
+      .textContent,
+  )
+    .toContain("Prefer explicit evidence.");
   expect(screen.getByRole("article", { name: "Resident context" })).not
     .toBeNull();
   expect(screen.getByText("Connected", { exact: true })).not.toBeNull();
@@ -292,6 +323,272 @@ test("renders a ready resident surface and committed Memory lifecycle states", a
     .toContain("cursor=memory-next");
 });
 
+test("edits and clears user-managed behavior with CAS while distinguishing save from Worker application", async () => {
+  const fetchMock = vi.fn(async (_path: string, init?: RequestInit) => {
+    const request = JSON.parse(String(init?.body));
+    return Response.json({
+      ...subject(),
+      behavior_md: request.behavior_md,
+      behavior_revision: request.expected_behavior_revision + 1,
+    });
+  });
+  vi.stubGlobal("fetch", fetchMock);
+  render(SubjectPage, {
+    data: {
+      workspaceId: "workspace-1",
+      subjectId: "subject-1",
+      subject: result(subject()),
+      surface: result({
+        subject_id: "subject-1",
+        availability: "ungenerated" as const,
+      }),
+      memories: result({ items: [], has_more: false }),
+    },
+  } as never);
+
+  await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+  const textarea = screen.getByRole("textbox", { name: "Subject behavior" });
+  await fireEvent.input(textarea, {
+    target: { value: "Ask before irreversible actions." },
+  });
+  await fireEvent.click(screen.getByRole("button", { name: "Save behavior" }));
+  await waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(1));
+  const [path, init] = fetchMock.mock.calls[0] as unknown as [
+    string,
+    RequestInit,
+  ];
+  expect(path).toBe("/api/w/workspace-1/subjektiv/subjects/subject-1/behavior");
+  expect(init.method).toBe("PATCH");
+  expect(init.body).toBe(
+    '{"expected_behavior_revision":2,"behavior_md":"Ask before irreversible actions."}',
+  );
+  await waitFor(() => {
+    expect(
+      screen.getByText(/Behavior storage confirmed at revision 3/).textContent,
+    )
+      .toContain("does not confirm application");
+  });
+  expect(
+    screen.getByRole("article", { name: "User-managed Subject behavior" })
+      .textContent,
+  )
+    .toContain("Ask before irreversible actions.");
+
+  await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+  await fireEvent.click(screen.getByRole("button", { name: "Clear" }));
+  await fireEvent.click(screen.getByRole("button", { name: "Save behavior" }));
+  await waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(2));
+  const secondBody =
+    (fetchMock.mock.calls[1] as unknown as [string, RequestInit])[1].body;
+  expect(secondBody).toBe('{"expected_behavior_revision":3,"behavior_md":""}');
+  await waitFor(() =>
+    expect(screen.getByText("No behavior is set.")).not.toBeNull()
+  );
+});
+
+function subjectPageData(record = subject(), workspaceId = "workspace-1") {
+  return {
+    workspaceId,
+    subjectId: record.id,
+    subject: result(record),
+    surface: result({
+      subject_id: record.id,
+      availability: "ungenerated" as const,
+    }),
+    memories: result({ items: [], has_more: false }),
+  };
+}
+
+test.each([
+  ["subject-2", "workspace-1"],
+  ["subject-1", "workspace-2"],
+])(
+  "resets reused Subject editor for %s in %s and saves only its own behavior",
+  async (id, workspaceId) => {
+    const nextSubject = { ...subject(), id, behavior_md: "Only B behavior." };
+    const fetchMock = vi.fn(async (_path: string, init?: RequestInit) => {
+      const request = JSON.parse(String(init?.body));
+      return Response.json({
+        ...nextSubject,
+        behavior_md: request.behavior_md,
+        behavior_revision: request.expected_behavior_revision + 1,
+      });
+    });
+    vi.stubGlobal("fetch", fetchMock);
+    const view = render(SubjectPage, { data: subjectPageData() } as never);
+    await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+    await fireEvent.input(
+      screen.getByRole("textbox", { name: "Subject behavior" }),
+      {
+        target: { value: "Unsaved A draft" },
+      },
+    );
+
+    await view.rerender(
+      { data: subjectPageData(nextSubject, workspaceId) } as never,
+    );
+    expect(screen.queryByRole("textbox", { name: "Subject behavior" }))
+      .toBeNull();
+    expect(
+      screen.getByRole("article", { name: "User-managed Subject behavior" })
+        .textContent,
+    )
+      .toContain("Only B behavior.");
+    await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+    expect(
+      (screen.getByRole("textbox", {
+        name: "Subject behavior",
+      }) as HTMLTextAreaElement).value,
+    )
+      .toBe("Only B behavior.");
+    await fireEvent.click(
+      screen.getByRole("button", { name: "Save behavior" }),
+    );
+    await waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(1));
+    const [path, init] = fetchMock.mock.calls[0] as unknown as [
+      string,
+      RequestInit,
+    ];
+    expect(path).toBe(
+      `/api/w/${workspaceId}/subjektiv/subjects/${id}/behavior`,
+    );
+    expect(JSON.parse(String(init.body))).toEqual({
+      expected_behavior_revision: 2,
+      behavior_md: "Only B behavior.",
+    });
+    await waitFor(() =>
+      expect(screen.getByText(/storage confirmed at revision 3/)).not.toBeNull()
+    );
+  },
+);
+
+test.each(["success", "failure"])(
+  "fences late %s from a previous Subject without clearing the new save state",
+  async (outcome) => {
+    const pending: Array<(response: Response) => void> = [];
+    const fetchMock = vi.fn(() =>
+      new Promise<Response>((resolve) => pending.push(resolve))
+    );
+    vi.stubGlobal("fetch", fetchMock);
+    const view = render(SubjectPage, { data: subjectPageData() } as never);
+    await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+    await fireEvent.click(
+      screen.getByRole("button", { name: "Save behavior" }),
+    );
+    await waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(1));
+
+    const nextSubject = {
+      ...subject(),
+      id: "subject-2",
+      behavior_md: "Only B behavior.",
+    };
+    await view.rerender({ data: subjectPageData(nextSubject) } as never);
+    await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+    await fireEvent.input(
+      screen.getByRole("textbox", { name: "Subject behavior" }),
+      {
+        target: { value: "Updated B behavior." },
+      },
+    );
+    await fireEvent.click(
+      screen.getByRole("button", { name: "Save behavior" }),
+    );
+    await waitFor(() => expect(fetchMock).toHaveBeenCalledTimes(2));
+    pending[0](
+      outcome === "success"
+        ? Response.json({
+          ...subject(),
+          behavior_md: "Late A response",
+          behavior_revision: 3,
+        })
+        : Response.json({
+          error: "Forbidden",
+          message: "A denied",
+          diagnostics: [],
+        }, { status: 403 }),
+    );
+    // Drain the previous response through its success/catch/finally branches.
+    await new Promise((resolve) => setTimeout(resolve, 0));
+    expect(
+      screen.getByRole("button", { name: "Saving…" }).hasAttribute("disabled"),
+    ).toBe(true);
+    expect(
+      (screen.getByRole("textbox", {
+        name: "Subject behavior",
+      }) as HTMLTextAreaElement).value,
+    )
+      .toBe("Updated B behavior.");
+    expect(screen.queryByRole("alert")).toBeNull();
+    expect(screen.queryByText(/storage confirmed/)).toBeNull();
+    pending[1](
+      Response.json({
+        ...nextSubject,
+        behavior_md: "Updated B behavior.",
+        behavior_revision: 3,
+      }),
+    );
+    await waitFor(() =>
+      expect(screen.getByText(/storage confirmed at revision 3/)).not.toBeNull()
+    );
+    expect(
+      screen.getByRole("article", { name: "User-managed Subject behavior" })
+        .textContent,
+    )
+      .toContain("Updated B behavior.");
+  },
+);
+
+test("a refreshed loader snapshot fences old saves even after returning to the same Subject", async () => {
+  let resolveRequest!: (response: Response) => void;
+  vi.stubGlobal(
+    "fetch",
+    vi.fn(() =>
+      new Promise<Response>((resolve) => {
+        resolveRequest = resolve;
+      })
+    ),
+  );
+  const view = render(SubjectPage, { data: subjectPageData() } as never);
+  await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+  await fireEvent.click(screen.getByRole("button", { name: "Save behavior" }));
+  await view.rerender(
+    { data: subjectPageData({ ...subject(), id: "subject-2" }) } as never,
+  );
+  const fresh = {
+    ...subject(),
+    behavior_md: "Fresh A loader",
+    behavior_revision: 4,
+  };
+  await view.rerender({ data: subjectPageData(fresh) } as never);
+  resolveRequest(
+    Response.json({
+      ...subject(),
+      behavior_md: "Stale A response",
+      behavior_revision: 3,
+    }),
+  );
+  await new Promise((resolve) => setTimeout(resolve, 0));
+  expect(
+    screen.getByRole("article", { name: "User-managed Subject behavior" })
+      .textContent,
+  )
+    .toContain("Fresh A loader");
+  expect(screen.queryByText(/storage confirmed/)).toBeNull();
+
+  await view.rerender(
+    {
+      data: {
+        ...subjectPageData(),
+        subject: result(null, "Subject unavailable"),
+      },
+    } as never,
+  );
+  expect(screen.queryByRole("button", { name: "Edit" })).toBeNull();
+  expect(
+    screen.queryByRole("article", { name: "User-managed Subject behavior" }),
+  ).toBeNull();
+});
+
 test("candidate-only Subjects show no committed Memories, not an inferred candidate count", () => {
   // The store regression candidate_decisions_reject_conflicts_and_roll_back_partial_writes
   // stages a candidate without committing a Memory. Its public read projection is
@@ -320,6 +617,65 @@ test("candidate-only Subjects show no committed Memories, not an inferred candid
   ).toBeNull();
 });
 
+test.each(["ready", "ungenerated", "stale", "failed"] as const)(
+  "user behavior and diagnostic disclosures stay independent of %s generated Memory",
+  async (availability) => {
+    const record = { ...subject(), store_revision: 0 };
+    const view = render(SubjectPage, {
+      data: {
+        ...subjectPageData(record),
+        surface: result({
+          subject_id: record.id,
+          availability,
+          ...(availability === "ready"
+            ? {
+              snapshot: {
+                snapshot_id: "empty-snapshot",
+                body_md: "",
+                memory_refs: [],
+                built_from_store_revision: 0,
+                created_at: "2026-01-02T03:04:05Z",
+              },
+            }
+            : {}),
+        }),
+      },
+    } as never);
+    expect(
+      screen.getByRole("article", { name: "User-managed Subject behavior" })
+        .textContent,
+    )
+      .toContain(record.behavior_md);
+    expect(screen.getByText("Generated Memory context", { exact: true })).not
+      .toBeNull();
+    expect(screen.getByText("No committed Memories yet.")).not.toBeNull();
+    expect(screen.getByText("Not connected", { exact: true })).not.toBeNull();
+    const technical = view.container.querySelector(
+      "details.subject-technical-details",
+    ) as HTMLDetailsElement;
+    expect(technical.open).toBe(false);
+    expect(technical.textContent).toContain("Subject store revision");
+    if (availability === "ready") {
+      expect(screen.getByText("Resident context is current but empty.")).not
+        .toBeNull();
+      expect(screen.getByText(/no generated Memory context to show/)).not
+        .toBeNull();
+      expect(
+        view.container.querySelector("details.surface-details")?.textContent,
+      )
+        .toContain("Generated from Subject revision");
+    }
+    await fireEvent.click(screen.getByRole("button", { name: "Edit" }));
+    await fireEvent.click(screen.getByRole("button", { name: "Cancel" }));
+    expect(
+      screen.getByRole("article", { name: "User-managed Subject behavior" })
+        .textContent,
+    )
+      .toContain(record.behavior_md);
+    expect(technical.open).toBe(false);
+  },
+);
+
 test("distinguishes ready-empty, stale, failed, unavailable, and request error surfaces", async () => {
   const base = {
     workspaceId: "workspace-1",

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

@@ -12,6 +12,7 @@ import {
   parseSubjektivSubjectListResponse,
   parseSubjektivSubjectResponse,
   SubjektivSubjectCreateError,
+  updateSubjektivSubjectBehavior,
   validateSubjektivSubjectCreateRequest,
 } from "../src/lib/workspace/memory/api.ts";
 
@@ -73,6 +74,8 @@ function subject(id = "subject-1") {
   return {
     id,
     role: "Release coordinator",
+    behavior_md: "Prefer explicit evidence.",
+    behavior_revision: 2,
     state: "active",
     store_revision: 12,
     created_at: "2026-09-01T00:00:00Z",
@@ -271,7 +274,7 @@ Deno.test("Subject list parser preserves the exact bounded response", () => {
 Deno.test("Subject create request mirrors Backend role validation without rewriting input", () => {
   assertEquals(
     validateSubjektivSubjectCreateRequest({ role: "  Release coordinator  " }),
-    { role: "  Release coordinator  " },
+    { role: "  Release coordinator  ", behavior_md: "" },
   );
   assertThrows(
     () => validateSubjektivSubjectCreateRequest({ role: "   " }),
@@ -285,6 +288,70 @@ Deno.test("Subject create request mirrors Backend role validation without rewrit
     () => validateSubjektivSubjectCreateRequest({ role: "界".repeat(86) }),
     "at most 256 bytes",
   );
+  assertThrows(
+    () =>
+      validateSubjektivSubjectCreateRequest({
+        role: "Reviewer",
+        behavior_md: " ".repeat(3),
+      }),
+    "empty or contain non-whitespace",
+  );
+  assertThrows(
+    () =>
+      validateSubjektivSubjectCreateRequest({
+        role: "Reviewer",
+        behavior_md: "x".repeat(16 * 1024 + 1),
+      }),
+    "at most 16384 bytes",
+  );
+});
+
+Deno.test("Subject behavior update uses CAS and preserves exact text", async () => {
+  const requests: Array<{ path: string; init?: RequestInit }> = [];
+  const fetchFn = (async (path: string | URL | Request, init?: RequestInit) => {
+    requests.push({ path: String(path), init });
+    return Response.json({
+      ...subject("subject/one"),
+      behavior_md: "Line one.\nLine two.",
+      behavior_revision: 3,
+    });
+  }) as typeof fetch;
+
+  const updated = await updateSubjektivSubjectBehavior(
+    fetchFn,
+    "workspace one",
+    "subject/one",
+    { expected_behavior_revision: 2, behavior_md: "Line one.\nLine two." },
+  );
+  assertEquals(updated.behavior_revision, 3);
+  assertEquals(updated.behavior_md, "Line one.\nLine two.");
+  assertEquals(
+    requests[0].path,
+    "/api/w/workspace%20one/subjektiv/subjects/subject%2Fone/behavior",
+  );
+  assertEquals(requests[0].init?.method, "PATCH");
+  assertEquals(
+    requests[0].init?.body,
+    '{"expected_behavior_revision":2,"behavior_md":"Line one.\\nLine two."}',
+  );
+});
+
+Deno.test("Subject behavior update reports conflicts without claiming Worker application", async () => {
+  const conflictFetch =
+    (async () =>
+      Response.json({ message: "revision conflict" }, {
+        status: 409,
+      })) as typeof fetch;
+  await assertSubjectCreateRejects(
+    () =>
+      updateSubjektivSubjectBehavior(conflictFetch, "workspace", "subject", {
+        expected_behavior_revision: 1,
+        behavior_md: "new",
+      }),
+    "rejected",
+    "changed elsewhere",
+    409,
+  );
 });
 
 Deno.test("Subject create client sends the exact typed body once and parses the created Subject", async () => {
@@ -294,20 +361,26 @@ Deno.test("Subject create client sends the exact typed body once and parses the
     return Response.json({
       ...subject("subject-created"),
       role: "  Release coordinator  ",
+      behavior_md: "Stay concise.",
     }, { status: 201 });
   }) as typeof fetch;
 
   const created = await createSubjektivSubject(fetchFn, "workspace one", {
     role: "  Release coordinator  ",
+    behavior_md: "Stay concise.",
   });
   assertEquals(created, {
     ...subject("subject-created"),
     role: "  Release coordinator  ",
+    behavior_md: "Stay concise.",
   });
   assertEquals(requests.length, 1);
   assertEquals(requests[0].path, "/api/w/workspace%20one/subjektiv/subjects");
   assertEquals(requests[0].init?.method, "POST");
-  assertEquals(requests[0].init?.body, '{"role":"  Release coordinator  "}');
+  assertEquals(
+    requests[0].init?.body,
+    '{"role":"  Release coordinator  ","behavior_md":"Stay concise."}',
+  );
 });
 
 Deno.test("Subject create client distinguishes rejected and unknown outcomes without retrying", async () => {