diff --git a/docs/architecture/chain-map-session-recovery.md b/docs/architecture/chain-map-session-recovery.md
index c0d236c2..7faca044 100644
--- a/docs/architecture/chain-map-session-recovery.md
+++ b/docs/architecture/chain-map-session-recovery.md
@@ -86,6 +86,21 @@ App side:
      └─ TaskThread lifecycleStatus → ready
 ```
 
+### S4a: Agent fails before producing output
+
+```
+OpenClaw agent_end(success=false, runId, error)
+  └─ openclaw-multi-session-plugins persists xworkmate.taskRuns[runId]
+     └─ App polls xworkmate.tasks.get
+        └─ Native detached-task record absent
+           └─ Plugin returns durable status=failed + sanitized error
+              └─ Bridge preserves terminal failure (no artifact wait)
+                 └─ App clears pending and shows the model/provider error
+
+expectedArtifactDirs remain scan hints. An empty reports/ or artifacts/
+directory cannot convert this terminal failure back to running.
+```
+
 ### S5: App resend on OpenClaw lane busy
 
 ```
@@ -165,7 +180,7 @@ No persistence:
 
 | Method | Params | Returns |
 |--------|--------|---------|
-| `xworkmate.tasks.get` | appThreadKey, openclawSessionKey, runId/taskId | Native task-registry snapshot or structured lookup error |
+| `xworkmate.tasks.get` | appThreadKey, openclawSessionKey, runId/taskId | Native task snapshot, durable agent_end run snapshot, or structured lookup error |
 | `xworkmate.tasks.cancel` | appThreadKey, openclawSessionKey, runId/taskId | Cancel confirmation |
 | Removed: Bridge task reassociation | artifactScope/runId-derived taskHandle | No longer supported; route through native task registry |
 
@@ -207,4 +222,4 @@ resolveGatewayThreadConnectionState(thread)
 
 4. **R4: Polling parameters**: Hardcoded poll interval/retry values in `ExternalCodeAgentAcpDesktopTransport` need to align with bridge's task deadlines (10/30/60 min). If polling stops before deadline, app marks failed while task is still running.
 
-5. **R5: OpenClaw handle expiration**: The bridge's `OpenClawTaskRecord` has no persistent storage. If the app stores a runId and later queries it after bridge restart, the lookup fails silently.
+5. **R5: OpenClaw handle expiration**: The bridge's in-memory `OpenClawTaskRecord` is not authoritative after restart. The plugin's SessionEntry-backed agent_end record preserves known terminal states; runs that ended before this record was written still fall back to the bounded deadline path.
diff --git a/docs/architecture/chain-map-task-execution.md b/docs/architecture/chain-map-task-execution.md
index 8a9e6949..bfb9a101 100644
--- a/docs/architecture/chain-map-task-execution.md
+++ b/docs/architecture/chain-map-task-execution.md
@@ -135,6 +135,11 @@ openclaw-multi-session-plugins
       │   └─ ["openclaw-multi-session-plugins"]["xworkmate.sessionMapping"]
       └─ Fail closed on appThreadKey/openclawSessionKey conflicts
 
+    Durable run terminal state
+      ├─ session.prepare records xworkmate.taskRuns[runId] = running
+      ├─ agent_end records completed/failed + sanitized error in SessionEntry.pluginExtensions
+      └─ xworkmate.tasks.get uses this record when chat.send has no native detached-task record
+
     prepareXWorkmateArtifacts()
       ├─ resolveWorkspaceDir() → workspace root
       ├─ safeScopeSegment(openclawSessionKey) → sanitize
@@ -201,9 +206,13 @@ now copied into tasks/<session>/<run>/artifacts/ before export.
     Bridge forwards typed lookup to the plugin/native task-registry.
     The request uses the persisted association:
       {appThreadKey, openclawSessionKey, runId/taskId}
-    Terminal state comes from native task records only. Missing native records
-    return structured errors such as no_native_task_record instead of inferring
-    success from artifacts or reconstructing a Bridge task dictionary.
+    Terminal state comes from native task records first, then from the plugin's
+    durable agent_end run record. Missing both returns structured errors such as
+    no_native_task_record instead of inferring success from artifacts.
+
+    expectedArtifactDirs only drive workspace-root discovery. They never keep a
+    terminal run in syncing-artifacts. Only explicit export flags or
+    requiredArtifactExtensions are blocking delivery contracts.
 
   Back to xworkmate-app:
     ExternalCodeAgentAcpDesktopTransport
@@ -264,3 +273,4 @@ etc.), not by extending the task execution lifecycle.
 5. **F5: Bridge restart** — In-memory sessions lost → app must detect and recover
 6. **F6: Artifact ref key rotation** — Secret change invalidates all signed refs
 7. **F7: SSE stream interruption** — Recovery polling must align with bridge task deadlines and must apply terminal snapshots immediately
+8. **F8: chat.send is not a detached task** — agent_end state must remain queryable by runId even when the native task registry has no record