From bb440c84b4ee703b2c6c601d421175698ccfac0c Mon Sep 17 00:00:00 2001
From: Michael Johnston <lastobelus@mac.com>
Date: Sun, 30 Aug 2026 13:55:29 -0700
Subject: [PATCH 1/5] feat(web): identify cross-thread agent messages

---
 apps/server/src/cli/thread.test.ts            | 26 +++++
 apps/server/src/cli/thread.ts                 |  7 ++
 .../Layers/ProjectionPipeline.ts              |  4 +
 .../Layers/ProjectionSnapshotQuery.test.ts    |  3 +
 .../Layers/ProjectionSnapshotQuery.ts         |  6 ++
 .../decider.projectScripts.test.ts            | 55 ++++++++++-
 apps/server/src/orchestration/decider.ts      | 16 ++++
 apps/server/src/orchestration/projector.ts    |  3 +
 .../Layers/ProjectionThreadMessages.test.ts   |  2 +
 .../Layers/ProjectionThreadMessages.ts        | 12 ++-
 apps/server/src/persistence/Migrations.ts     |  2 +
 .../051_ProjectionThreadMessageSource.test.ts | 31 ++++++
 .../051_ProjectionThreadMessageSource.ts      | 16 ++++
 .../Services/ProjectionThreadMessages.ts      |  1 +
 apps/web/src/components/ChatView.tsx          | 11 +++
 .../src/components/ThreadStatusIndicators.tsx |  2 +-
 .../components/chat/MessagesTimeline.test.tsx | 49 +++++++++-
 .../src/components/chat/MessagesTimeline.tsx  | 96 ++++++++++++++++++-
 docs/user/codex-thread-tools.md               |  4 +
 .../src/state/threadReducer.test.ts           |  2 +
 .../client-runtime/src/state/threadReducer.ts |  3 +
 packages/contracts/src/orchestration.test.ts  | 44 +++++++++
 packages/contracts/src/orchestration.ts       |  4 +
 23 files changed, 393 insertions(+), 6 deletions(-)
 create mode 100644 apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.test.ts
 create mode 100644 apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.ts

diff --git a/apps/server/src/cli/thread.test.ts b/apps/server/src/cli/thread.test.ts
index 7eb2172e8291..dcb4afc1d883 100644
--- a/apps/server/src/cli/thread.test.ts
+++ b/apps/server/src/cli/thread.test.ts
@@ -622,6 +622,7 @@ it.effect("prepares and dispatches an exact accepted send using the target threa
       commandId: CommandId.make("command-send"),
       messageId: MessageId.make("message-send"),
       createdAt: "2026-08-22T00:00:00.000Z",
+      sourceThreadId: ThreadId.make("thread-source"),
     });
 
     assert.deepStrictEqual(result, {
@@ -643,12 +644,37 @@ it.effect("prepares and dispatches an exact accepted send using the target threa
         },
         runtimeMode: "approval-required",
         interactionMode: "plan",
+        sourceThreadId: "thread-source",
         createdAt: "2026-08-22T00:00:00.000Z",
       },
     ]);
   }),
 );
 
+it.effect("does not mark a send to the current thread as cross-thread", () =>
+  Effect.gen(function* () {
+    const { source } = runnerSource();
+    const dispatched: unknown[] = [];
+    yield* sendThreadOutput(
+      {
+        descriptor: source.descriptor,
+        shell: source.shell,
+        dispatch: (command) => Effect.sync(() => dispatched.push(command)),
+      },
+      {
+        identifier: "thread-runner",
+        message: "status",
+        commandId: CommandId.make("command-self-send"),
+        messageId: MessageId.make("message-self-send"),
+        createdAt: "2026-08-22T00:00:00.000Z",
+        sourceThreadId: ThreadId.make("thread-runner"),
+      },
+    );
+
+    assert.notProperty(dispatched[0] as object, "sourceThreadId");
+  }),
+);
+
 it.effect("marks only explicitly tracked sends for wait correlation", () =>
   Effect.gen(function* () {
     const { source } = runnerSource();
diff --git a/apps/server/src/cli/thread.ts b/apps/server/src/cli/thread.ts
index 8f1dc2026280..e3a413537d57 100644
--- a/apps/server/src/cli/thread.ts
+++ b/apps/server/src/cli/thread.ts
@@ -512,6 +512,7 @@ export const sendThreadOutput = Effect.fn("sendThreadOutput")(function* (
     readonly commandId: CommandId;
     readonly messageId: MessageId;
     readonly createdAt: string;
+    readonly sourceThreadId?: ThreadId;
     readonly trackRequestCorrelation?: true;
     readonly rejectWaitForThreadId?: ThreadId;
   },
@@ -558,6 +559,9 @@ export const sendThreadOutput = Effect.fn("sendThreadOutput")(function* (
     },
     runtimeMode: resolution.thread.runtimeMode,
     interactionMode: resolution.thread.interactionMode,
+    ...(input.sourceThreadId !== undefined && input.sourceThreadId !== resolution.thread.id
+      ? { sourceThreadId: input.sourceThreadId }
+      : {}),
     ...(input.trackRequestCorrelation === true ? { trackRequestCorrelation: true } : {}),
     createdAt: input.createdAt,
   });
@@ -946,6 +950,9 @@ const runThreadSend = Effect.fn("runThreadSend")(function* (
               commandId,
               messageId,
               createdAt: DateTime.formatIso(yield* DateTime.now),
+              ...(process.env.T3CODE_THREAD_ID?.trim()
+                ? { sourceThreadId: ThreadId.make(process.env.T3CODE_THREAD_ID.trim()) }
+                : {}),
               ...(waitForCompletion ? { trackRequestCorrelation: true as const } : {}),
               ...(waitForCompletion && process.env.T3CODE_THREAD_ID?.trim()
                 ? { rejectWaitForThreadId: ThreadId.make(process.env.T3CODE_THREAD_ID.trim()) }
diff --git a/apps/server/src/orchestration/Layers/ProjectionPipeline.ts b/apps/server/src/orchestration/Layers/ProjectionPipeline.ts
index 4da34eca72ae..e6b05e968485 100644
--- a/apps/server/src/orchestration/Layers/ProjectionPipeline.ts
+++ b/apps/server/src/orchestration/Layers/ProjectionPipeline.ts
@@ -1083,6 +1083,10 @@ const makeOrchestrationProjectionPipeline = Effect.fn("makeOrchestrationProjecti
             role: event.payload.role,
             text: nextText,
             ...(nextAttachments !== undefined ? { attachments: [...nextAttachments] } : {}),
+            ...(event.payload.sourceThreadId !== undefined ||
+            previousMessage?.sourceThreadId !== undefined
+              ? { sourceThreadId: event.payload.sourceThreadId ?? previousMessage?.sourceThreadId }
+              : {}),
             isStreaming: event.payload.streaming,
             createdAt: previousMessage?.createdAt ?? event.payload.createdAt,
             updatedAt: event.payload.updatedAt,
diff --git a/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.test.ts b/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.test.ts
index 6c6f8f662c41..2556d88f82ac 100644
--- a/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.test.ts
+++ b/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.test.ts
@@ -130,6 +130,7 @@ projectionSnapshotLayer("ProjectionSnapshotQuery", (it) => {
           turn_id,
           role,
           text,
+          source_thread_id,
           is_streaming,
           created_at,
           updated_at
@@ -140,6 +141,7 @@ projectionSnapshotLayer("ProjectionSnapshotQuery", (it) => {
           'turn-1',
           'assistant',
           'hello from projection',
+          'thread-source',
           0,
           '2026-02-24T00:00:04.000Z',
           '2026-02-24T00:00:05.000Z'
@@ -354,6 +356,7 @@ projectionSnapshotLayer("ProjectionSnapshotQuery", (it) => {
               id: asMessageId("message-1"),
               role: "assistant",
               text: "hello from projection",
+              sourceThreadId: ThreadId.make("thread-source"),
               turnId: asTurnId("turn-1"),
               streaming: false,
               createdAt: "2026-02-24T00:00:04.000Z",
diff --git a/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts b/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts
index 3ab5e3b503db..5c5a2905e63d 100644
--- a/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts
+++ b/apps/server/src/orchestration/Layers/ProjectionSnapshotQuery.ts
@@ -87,6 +87,7 @@ const ProjectionThreadMessageDbRowSchema = ProjectionThreadMessage.mapFields(
   Struct.assign({
     isStreaming: Schema.Number,
     attachments: Schema.NullOr(Schema.fromJsonString(Schema.Array(ChatAttachment))),
+    sourceThreadId: Schema.NullOr(ThreadId),
   }),
 );
 const ProjectionThreadProposedPlanDbRowSchema = ProjectionThreadProposedPlan;
@@ -560,6 +561,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           role,
           text,
           attachments_json AS "attachments",
+          source_thread_id AS "sourceThreadId",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
           updated_at AS "updatedAt"
@@ -1008,6 +1010,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           role,
           text,
           attachments_json AS "attachments",
+          source_thread_id AS "sourceThreadId",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
           updated_at AS "updatedAt"
@@ -1255,6 +1258,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
           role,
           text,
           attachments_json AS "attachments",
+          source_thread_id AS "sourceThreadId",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
           updated_at AS "updatedAt"
@@ -1597,6 +1601,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
                   role: row.role,
                   text: row.text,
                   ...(row.attachments !== null ? { attachments: row.attachments } : {}),
+                  ...(row.sourceThreadId !== null ? { sourceThreadId: row.sourceThreadId } : {}),
                   turnId: row.turnId,
                   streaming: row.isStreaming === 1,
                   createdAt: row.createdAt,
@@ -2699,6 +2704,7 @@ const makeProjectionSnapshotQuery = Effect.gen(function* () {
             id: row.messageId,
             role: row.role,
             text: row.text,
+            ...(row.sourceThreadId !== null ? { sourceThreadId: row.sourceThreadId } : {}),
             turnId: row.turnId,
             streaming: row.isStreaming === 1,
             createdAt: row.createdAt,
diff --git a/apps/server/src/orchestration/decider.projectScripts.test.ts b/apps/server/src/orchestration/decider.projectScripts.test.ts
index bf5c509fa16b..05779b7a8d3b 100644
--- a/apps/server/src/orchestration/decider.projectScripts.test.ts
+++ b/apps/server/src/orchestration/decider.projectScripts.test.ts
@@ -271,7 +271,7 @@ it.layer(NodeServices.layer)("decider project scripts", (it) => {
           updatedAt: now,
         },
       });
-      const readModel = yield* projectEvent(withProject, {
+      const withTargetThread = yield* projectEvent(withProject, {
         sequence: 2,
         eventId: asEventId("evt-thread-create"),
         aggregateKind: "thread",
@@ -298,6 +298,33 @@ it.layer(NodeServices.layer)("decider project scripts", (it) => {
           updatedAt: now,
         },
       });
+      const readModel = yield* projectEvent(withTargetThread, {
+        sequence: 3,
+        eventId: asEventId("evt-source-thread-create"),
+        aggregateKind: "thread",
+        aggregateId: ThreadId.make("thread-source"),
+        type: "thread.created",
+        occurredAt: now,
+        commandId: CommandId.make("cmd-source-thread-create"),
+        causationEventId: null,
+        correlationId: CommandId.make("cmd-source-thread-create"),
+        metadata: {},
+        payload: {
+          threadId: ThreadId.make("thread-source"),
+          projectId: asProjectId("project-1"),
+          title: "Source thread",
+          modelSelection: {
+            instanceId: ProviderInstanceId.make("codex"),
+            model: "gpt-5-codex",
+          },
+          interactionMode: DEFAULT_PROVIDER_INTERACTION_MODE,
+          runtimeMode: "approval-required",
+          branch: null,
+          worktreePath: null,
+          createdAt: now,
+          updatedAt: now,
+        },
+      });
 
       const result = yield* decideOrchestrationCommand({
         command: {
@@ -316,6 +343,7 @@ it.layer(NodeServices.layer)("decider project scripts", (it) => {
           ]),
           interactionMode: DEFAULT_PROVIDER_INTERACTION_MODE,
           runtimeMode: "approval-required",
+          sourceThreadId: ThreadId.make("thread-source"),
           createdAt: now,
         },
         readModel,
@@ -325,6 +353,9 @@ it.layer(NodeServices.layer)("decider project scripts", (it) => {
       const events = Array.isArray(result) ? result : [result];
       expect(events).toHaveLength(2);
       expect(events[0]?.type).toBe("thread.message-sent");
+      if (events[0]?.type === "thread.message-sent") {
+        expect(events[0].payload.sourceThreadId).toBe("thread-source");
+      }
       const turnStartEvent = events[1];
       expect(turnStartEvent?.type).toBe("thread.turn-start-requested");
       expect(turnStartEvent?.causationEventId).toBe(events[0]?.eventId ?? null);
@@ -340,6 +371,28 @@ it.layer(NodeServices.layer)("decider project scripts", (it) => {
         ]),
         runtimeMode: "approval-required",
       });
+
+      const selfSourceFailure = yield* Effect.flip(
+        decideOrchestrationCommand({
+          command: {
+            type: "thread.turn.start",
+            commandId: CommandId.make("cmd-self-source"),
+            threadId: ThreadId.make("thread-1"),
+            sourceThreadId: ThreadId.make("thread-1"),
+            message: {
+              messageId: asMessageId("message-self-source"),
+              role: "user",
+              text: "hello",
+              attachments: [],
+            },
+            interactionMode: DEFAULT_PROVIDER_INTERACTION_MODE,
+            runtimeMode: "approval-required",
+            createdAt: now,
+          },
+          readModel,
+        }),
+      );
+      expect(selfSourceFailure.message).toContain("must differ from its target thread");
     }),
   );
 
diff --git a/apps/server/src/orchestration/decider.ts b/apps/server/src/orchestration/decider.ts
index 774d92a64311..9afc8c00c02e 100644
--- a/apps/server/src/orchestration/decider.ts
+++ b/apps/server/src/orchestration/decider.ts
@@ -1367,6 +1367,19 @@ export const decideOrchestrationCommand = Effect.fn("decideOrchestrationCommand"
         command,
         threadId: command.threadId,
       });
+      if (command.sourceThreadId === command.threadId) {
+        return yield* new OrchestrationCommandInvariantError({
+          commandType: command.type,
+          detail: "A cross-thread message source must differ from its target thread.",
+        });
+      }
+      if (command.sourceThreadId !== undefined) {
+        yield* requireThread({
+          readModel,
+          command,
+          threadId: command.sourceThreadId,
+        });
+      }
       const sourceProposedPlan = command.sourceProposedPlan;
       const sourceThread = sourceProposedPlan
         ? yield* requireThread({
@@ -1405,6 +1418,9 @@ export const decideOrchestrationCommand = Effect.fn("decideOrchestrationCommand"
           role: command.message.role,
           text: command.message.text,
           attachments: command.message.attachments,
+          ...(command.sourceThreadId !== undefined
+            ? { sourceThreadId: command.sourceThreadId }
+            : {}),
           turnId: null,
           streaming: false,
           createdAt: command.createdAt,
diff --git a/apps/server/src/orchestration/projector.ts b/apps/server/src/orchestration/projector.ts
index 984dc93cd1b8..f4a79b0f731b 100644
--- a/apps/server/src/orchestration/projector.ts
+++ b/apps/server/src/orchestration/projector.ts
@@ -577,6 +577,9 @@ export function projectEvent(
             role: payload.role,
             text: payload.text,
             ...(payload.attachments !== undefined ? { attachments: payload.attachments } : {}),
+            ...(payload.sourceThreadId !== undefined
+              ? { sourceThreadId: payload.sourceThreadId }
+              : {}),
             turnId: payload.turnId,
             streaming: payload.streaming,
             createdAt: payload.createdAt,
diff --git a/apps/server/src/persistence/Layers/ProjectionThreadMessages.test.ts b/apps/server/src/persistence/Layers/ProjectionThreadMessages.test.ts
index b1f394a9e577..d7b6bc11a80c 100644
--- a/apps/server/src/persistence/Layers/ProjectionThreadMessages.test.ts
+++ b/apps/server/src/persistence/Layers/ProjectionThreadMessages.test.ts
@@ -36,6 +36,7 @@ layer("ProjectionThreadMessageRepository", (it) => {
         role: "user",
         text: "initial",
         attachments: persistedAttachments,
+        sourceThreadId: ThreadId.make("thread-source"),
         isStreaming: false,
         createdAt,
         updatedAt,
@@ -62,6 +63,7 @@ layer("ProjectionThreadMessageRepository", (it) => {
       if (rowById._tag === "Some") {
         assert.equal(rowById.value.text, "updated");
         assert.deepEqual(rowById.value.attachments, persistedAttachments);
+        assert.equal(rowById.value.sourceThreadId, "thread-source");
       }
     }),
   );
diff --git a/apps/server/src/persistence/Layers/ProjectionThreadMessages.ts b/apps/server/src/persistence/Layers/ProjectionThreadMessages.ts
index 719191668869..4ff6e4483a80 100644
--- a/apps/server/src/persistence/Layers/ProjectionThreadMessages.ts
+++ b/apps/server/src/persistence/Layers/ProjectionThreadMessages.ts
@@ -5,7 +5,7 @@ import * as Layer from "effect/Layer";
 import * as Option from "effect/Option";
 import * as Schema from "effect/Schema";
 import * as Struct from "effect/Struct";
-import { ChatAttachment } from "@t3tools/contracts";
+import { ChatAttachment, ThreadId } from "@t3tools/contracts";
 
 import { toPersistenceSqlError } from "../Errors.ts";
 import {
@@ -21,6 +21,7 @@ const ProjectionThreadMessageDbRowSchema = ProjectionThreadMessage.mapFields(
   Struct.assign({
     isStreaming: Schema.Number,
     attachments: Schema.NullOr(Schema.fromJsonString(Schema.Array(ChatAttachment))),
+    sourceThreadId: Schema.NullOr(ThreadId),
   }),
 );
 
@@ -37,6 +38,7 @@ function toProjectionThreadMessage(
     createdAt: row.createdAt,
     updatedAt: row.updatedAt,
     ...(row.attachments !== null ? { attachments: row.attachments } : {}),
+    ...(row.sourceThreadId !== null ? { sourceThreadId: row.sourceThreadId } : {}),
   };
 }
 
@@ -56,6 +58,7 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           role,
           text,
           attachments_json,
+          source_thread_id,
           is_streaming,
           created_at,
           updated_at
@@ -74,6 +77,7 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
               WHERE message_id = ${row.messageId}
             )
           ),
+          ${row.sourceThreadId ?? null},
           ${row.isStreaming ? 1 : 0},
           ${row.createdAt},
           ${row.updatedAt}
@@ -88,6 +92,10 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
             excluded.attachments_json,
             projection_thread_messages.attachments_json
           ),
+          source_thread_id = COALESCE(
+            excluded.source_thread_id,
+            projection_thread_messages.source_thread_id
+          ),
           is_streaming = excluded.is_streaming,
           created_at = excluded.created_at,
           updated_at = excluded.updated_at
@@ -107,6 +115,7 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           role,
           text,
           attachments_json AS "attachments",
+          source_thread_id AS "sourceThreadId",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
           updated_at AS "updatedAt"
@@ -128,6 +137,7 @@ const makeProjectionThreadMessageRepository = Effect.gen(function* () {
           role,
           text,
           attachments_json AS "attachments",
+          source_thread_id AS "sourceThreadId",
           is_streaming AS "isStreaming",
           created_at AS "createdAt",
           updated_at AS "updatedAt"
diff --git a/apps/server/src/persistence/Migrations.ts b/apps/server/src/persistence/Migrations.ts
index 02df09d6669d..5447d209ad68 100644
--- a/apps/server/src/persistence/Migrations.ts
+++ b/apps/server/src/persistence/Migrations.ts
@@ -63,6 +63,7 @@ import Migration0047 from "./Migrations/047_ProjectionTurnRequestCorrelations.ts
 import Migration0048 from "./Migrations/048_ProjectionThreadWorktreeCleanup.ts";
 import Migration0049 from "./Migrations/049_ProjectionThreadLinkedPullRequest.ts";
 import Migration0050 from "./Migrations/050_ProjectionThreadsUnsettledAt.ts";
+import Migration0051 from "./Migrations/051_ProjectionThreadMessageSource.ts";
 
 /**
  * Migration loader with all migrations defined inline.
@@ -125,6 +126,7 @@ export const migrationEntries = [
   [48, "ProjectionThreadWorktreeCleanup", Migration0048],
   [49, "ProjectionThreadLinkedPullRequest", Migration0049],
   [50, "ProjectionThreadsUnsettledAt", Migration0050],
+  [51, "ProjectionThreadMessageSource", Migration0051],
 ] as const;
 
 export const migrationManifest = migrationEntries.map(([id, name]) => [id, name] as const);
diff --git a/apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.test.ts b/apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.test.ts
new file mode 100644
index 000000000000..5e27f9f4fa89
--- /dev/null
+++ b/apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.test.ts
@@ -0,0 +1,31 @@
+import { assert, it } from "@effect/vitest";
+import * as Effect from "effect/Effect";
+import * as Layer from "effect/Layer";
+import * as SqlClient from "effect/unstable/sql/SqlClient";
+
+import { runMigrations } from "../Migrations.ts";
+import * as NodeSqliteClient from "../NodeSqliteClient.ts";
+
+const layer = it.layer(Layer.mergeAll(NodeSqliteClient.layerMemory()));
+
+layer("051_ProjectionThreadMessageSource", (it) => {
+  it.effect("adds nullable source thread provenance to projected messages", () =>
+    Effect.gen(function* () {
+      const sql = yield* SqlClient.SqlClient;
+
+      yield* runMigrations({ toMigrationInclusive: 50 });
+      const before = yield* sql<{ readonly name: string }>`
+        PRAGMA table_info(projection_thread_messages)
+      `;
+      assert.isFalse(before.some((column) => column.name === "source_thread_id"));
+
+      const executed = yield* runMigrations({ toMigrationInclusive: 51 });
+      assert.deepStrictEqual(executed, [[51, "ProjectionThreadMessageSource"]]);
+
+      const after = yield* sql<{ readonly name: string }>`
+        PRAGMA table_info(projection_thread_messages)
+      `;
+      assert.equal(after.filter((column) => column.name === "source_thread_id").length, 1);
+    }),
+  );
+});
diff --git a/apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.ts b/apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.ts
new file mode 100644
index 000000000000..14410b25199f
--- /dev/null
+++ b/apps/server/src/persistence/Migrations/051_ProjectionThreadMessageSource.ts
@@ -0,0 +1,16 @@
+import * as Effect from "effect/Effect";
+import * as SqlClient from "effect/unstable/sql/SqlClient";
+
+export default Effect.gen(function* () {
+  const sql = yield* SqlClient.SqlClient;
+  const columns = yield* sql<{ readonly name: string }>`
+    PRAGMA table_info(projection_thread_messages)
+  `;
+
+  if (!columns.some((column) => column.name === "source_thread_id")) {
+    yield* sql`
+      ALTER TABLE projection_thread_messages
+      ADD COLUMN source_thread_id TEXT
+    `;
+  }
+});
diff --git a/apps/server/src/persistence/Services/ProjectionThreadMessages.ts b/apps/server/src/persistence/Services/ProjectionThreadMessages.ts
index d50ff3202563..9559629af63e 100644
--- a/apps/server/src/persistence/Services/ProjectionThreadMessages.ts
+++ b/apps/server/src/persistence/Services/ProjectionThreadMessages.ts
@@ -28,6 +28,7 @@ export const ProjectionThreadMessage = Schema.Struct({
   role: OrchestrationMessageRole,
   text: Schema.String,
   attachments: Schema.optional(Schema.Array(ChatAttachment)),
+  sourceThreadId: Schema.optional(ThreadId),
   isStreaming: Schema.Boolean,
   createdAt: IsoDateTime,
   updatedAt: IsoDateTime,
diff --git a/apps/web/src/components/ChatView.tsx b/apps/web/src/components/ChatView.tsx
index df2c61a7eae8..aeaff1d20cdc 100644
--- a/apps/web/src/components/ChatView.tsx
+++ b/apps/web/src/components/ChatView.tsx
@@ -1863,6 +1863,16 @@ function ChatViewContent(props: ChatViewProps) {
     : null;
   const projectGroupingSettings = useClientSettings(selectProjectGroupingSettings);
   const clientSettingsHydrated = useClientSettingsHydrated();
+  const openAgentMessageSourceThread = useCallback(
+    (threadId: ThreadId) => {
+      if (!activeThread) return;
+      void navigate({
+        to: "/$environmentId/$threadId",
+        params: buildThreadRouteParams(scopeThreadRef(activeThread.environmentId, threadId)),
+      });
+    },
+    [activeThread, navigate],
+  );
   const [pendingFileSurfaceIdsByProject, setPendingFileSurfaceIdsByProject] = useState<
     ReadonlyMap<string, ReadonlySet<string>>
   >(() => new Map());
@@ -7405,6 +7415,7 @@ function ChatViewContent(props: ChatViewProps) {
                 runningTurnId={activeRunningTurnId}
                 turnDiffSummaryByAssistantMessageId={turnDiffSummaryByAssistantMessageId}
                 activeThreadEnvironmentId={activeThread.environmentId}
+                onOpenSourceThread={openAgentMessageSourceThread}
                 routeThreadKey={routeThreadKey}
                 onOpenTurnDiff={onOpenTurnDiff}
                 revertTurnCountByUserMessageId={revertTurnCountByUserMessageId}
diff --git a/apps/web/src/components/ThreadStatusIndicators.tsx b/apps/web/src/components/ThreadStatusIndicators.tsx
index 9c8a28209a2d..9b43251f0d3c 100644
--- a/apps/web/src/components/ThreadStatusIndicators.tsx
+++ b/apps/web/src/components/ThreadStatusIndicators.tsx
@@ -467,7 +467,7 @@ export function ThreadStatusLabel({
   status,
   compact = false,
 }: {
-  status: ThreadStatusPill;
+  status: Pick<ThreadStatusPill, "colorClass" | "dotClass" | "pulse"> & { label: string };
   compact?: boolean;
 }) {
   if (compact) {
diff --git a/apps/web/src/components/chat/MessagesTimeline.test.tsx b/apps/web/src/components/chat/MessagesTimeline.test.tsx
index 0bdccab23133..eb927fc800cc 100644
--- a/apps/web/src/components/chat/MessagesTimeline.test.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.test.tsx
@@ -1,4 +1,4 @@
-import { CheckpointRef, EnvironmentId, MessageId, TurnId } from "@t3tools/contracts";
+import { CheckpointRef, EnvironmentId, MessageId, ThreadId, TurnId } from "@t3tools/contracts";
 import { codexFeedbackMessage } from "@t3tools/client-runtime/state/threads";
 import { formatActionResumeFollowUp } from "@t3tools/shared/actionResume";
 import { createRef, type ReactNode, type Ref } from "react";
@@ -127,6 +127,26 @@ vi.mock("@pierre/diffs/react", () => {
   return { FileDiff: MockFileDiff };
 });
 
+vi.mock("../../state/entities", async (importOriginal) => {
+  const actual = await importOriginal<typeof import("../../state/entities")>();
+  return {
+    ...actual,
+    useThreadShell: () => ({
+      id: ThreadId.make("thread-source"),
+      title: "Mobile Reconnect Issue",
+      hasActionableProposedPlan: false,
+      hasPendingApprovals: false,
+      hasPendingUserInput: false,
+      interactionMode: "default",
+      latestTurn: null,
+      session: { status: "running" },
+      backgroundLiveness: null,
+      actionResume: null,
+      worktreeCleanup: null,
+    }),
+  };
+});
+
 function matchMedia() {
   return {
     matches: false,
@@ -238,6 +258,33 @@ function buildAssistantTimelineEntry(text: string) {
 }
 
 describe("MessagesTimeline", () => {
+  it("renders cross-thread posts as left-aligned agent message cards", () => {
+    const sourceThreadId = ThreadId.make("thread-source");
+    const entry = buildUserTimelineEntry("The reconnect fix is ready for review.");
+    const markup = renderToStaticMarkup(
+      <MessagesTimeline
+        {...buildProps()}
+        timelineEntries={[
+          {
+            ...entry,
+            message: { ...entry.message, sourceThreadId },
+          },
+        ]}
+      />,
+    );
+
+    expect(markup).toContain("AGENT MESSAGE");
+    expect(markup).toContain("Mobile Reconnect Issue");
+    expect(markup).toContain("Working");
+    expect(markup).toContain("items-start");
+    expect(markup).toContain("max-w-[80%]");
+    expect(markup).toContain("border-primary/55 bg-secondary");
+    expect(markup).toContain("font-medium lowercase text-primary");
+    expect(markup).toContain('aria-label="Open source thread: Mobile Reconnect Issue"');
+    expect(markup).not.toContain("Open source thread</a>");
+    expect(markup).not.toContain("bg-message p-3");
+  });
+
   it("shows compact completed Action results without embedding detailed output", () => {
     const actionText = formatActionResumeFollowUp({
       actionName: "Run Full CI",
diff --git a/apps/web/src/components/chat/MessagesTimeline.tsx b/apps/web/src/components/chat/MessagesTimeline.tsx
index 8b9908af56df..b8d69c8c8e95 100644
--- a/apps/web/src/components/chat/MessagesTimeline.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.tsx
@@ -5,9 +5,10 @@ import {
   type ScopedThreadRef,
   type ServerProviderSkill,
   type ThreadAnnotation,
+  type ThreadId,
   type TurnId,
 } from "@t3tools/contracts";
-import { parseScopedThreadKey } from "@t3tools/client-runtime/environment";
+import { parseScopedThreadKey, scopeThreadRef } from "@t3tools/client-runtime/environment";
 import type { AgentPanelModel } from "@t3tools/client-runtime/state/subagentRuntime";
 import {
   emptyAgentPanelModel,
@@ -16,6 +17,7 @@ import {
 
 const EMPTY_AGENT_PANEL_MODEL = emptyAgentPanelModel();
 const NOOP_OPEN_AGENTS = () => {};
+const NOOP_OPEN_SOURCE_THREAD = (_threadId: ThreadId) => {};
 const NOOP_DOWNLOAD_ATTACHMENT = (_attachment: ChatFileAttachment) => {};
 import { resolveChatListAnchoredEndSpace } from "@t3tools/shared/chatList";
 import { actionResultPresentation, parseActionResumeFollowUp } from "@t3tools/shared/actionResume";
@@ -55,6 +57,7 @@ import {
 } from "../../lib/diffRendering";
 import ChatMarkdown from "../ChatMarkdown";
 import {
+  ArrowUpRightIcon,
   BotIcon,
   CheckIcon,
   ChevronDownIcon,
@@ -135,6 +138,10 @@ import {
 } from "./userMessageTerminalContexts";
 import { SkillInlineText } from "./SkillInlineText";
 import { formatWorkspaceRelativePath } from "../../filePathDisplay";
+import { resolveThreadStatusPill } from "../Sidebar.logic";
+import { ThreadStatusLabel } from "../ThreadStatusIndicators";
+import { useClientSettings } from "../../hooks/useSettings";
+import { useThreadShell } from "../../state/entities";
 import {
   buildReviewCommentRenderablePatch,
   formatReviewCommentFence,
@@ -158,6 +165,7 @@ interface TimelineRowSharedState {
   workspaceRoot: string | undefined;
   skills: ReadonlyArray<Pick<ServerProviderSkill, "name" | "displayName">>;
   activeThreadEnvironmentId: EnvironmentId;
+  onOpenSourceThread: (threadId: ThreadId) => void;
   onRevertUserMessage: (messageId: MessageId) => void;
   onImageExpand: (preview: ExpandedImagePreview) => void;
   onFileDownload: (attachment: ChatFileAttachment) => void;
@@ -244,6 +252,7 @@ interface MessagesTimelineProps {
   onImageExpand: (preview: ExpandedImagePreview) => void;
   onFileDownload?: (attachment: ChatFileAttachment) => void;
   activeThreadEnvironmentId: EnvironmentId;
+  onOpenSourceThread?: (threadId: ThreadId) => void;
   markdownCwd: string | undefined;
   resolvedTheme: "light" | "dark";
   timestampFormat: TimestampFormat;
@@ -296,6 +305,7 @@ export const MessagesTimeline = memo(function MessagesTimeline({
   onImageExpand,
   onFileDownload = NOOP_DOWNLOAD_ATTACHMENT,
   activeThreadEnvironmentId,
+  onOpenSourceThread = NOOP_OPEN_SOURCE_THREAD,
   markdownCwd,
   resolvedTheme,
   timestampFormat,
@@ -576,6 +586,7 @@ export const MessagesTimeline = memo(function MessagesTimeline({
       workspaceRoot,
       skills,
       activeThreadEnvironmentId,
+      onOpenSourceThread,
       onRevertUserMessage,
       onImageExpand,
       onFileDownload,
@@ -595,6 +606,7 @@ export const MessagesTimeline = memo(function MessagesTimeline({
       workspaceRoot,
       skills,
       activeThreadEnvironmentId,
+      onOpenSourceThread,
       onRevertUserMessage,
       onImageExpand,
       onFileDownload,
@@ -1206,7 +1218,16 @@ const TimelineRowContent = memo(function TimelineRowContent({ row }: { row: Time
       {row.kind === "work-live" ? <LiveWorkEntryTimelineRow row={row} /> : null}
       {row.kind === "work-toggle" ? <WorkGroupToggleTimelineRow row={row} /> : null}
       {row.kind === "turn-fold" ? <TurnFoldTimelineRow row={row} /> : null}
-      {row.kind === "message" && row.message.role === "user" ? <UserTimelineRow row={row} /> : null}
+      {row.kind === "message" &&
+      row.message.role === "user" &&
+      row.message.sourceThreadId !== undefined ? (
+        <AgentMessageTimelineRow row={row} sourceThreadId={row.message.sourceThreadId} />
+      ) : null}
+      {row.kind === "message" &&
+      row.message.role === "user" &&
+      row.message.sourceThreadId === undefined ? (
+        <UserTimelineRow row={row} />
+      ) : null}
       {row.kind === "message" && row.message.role === "assistant" ? (
         <AssistantTimelineRow row={row} />
       ) : null}
@@ -1221,6 +1242,77 @@ const TimelineRowContent = memo(function TimelineRowContent({ row }: { row: Time
   );
 });
 
+function AgentMessageTimelineRow({
+  row,
+  sourceThreadId,
+}: {
+  row: Extract<TimelineRow, { kind: "message" }>;
+  sourceThreadId: ThreadId;
+}) {
+  const ctx = use(TimelineRowCtx);
+
+  const source = useThreadShell(scopeThreadRef(ctx.activeThreadEnvironmentId, sourceThreadId));
+  const compactStatus = useClientSettings((settings) => settings.compactLegacySidebarStatuses);
+  const status = source
+    ? (resolveThreadStatusPill({ thread: source }) ??
+      (source.session?.status === "error"
+        ? {
+            label: "Failed",
+            colorClass: "text-red-700 dark:text-red-300",
+            dotClass: "bg-red-600 dark:bg-red-300",
+            pulse: false,
+          }
+        : {
+            label: "Ready",
+            colorClass: "text-muted-foreground",
+            dotClass: "bg-muted-foreground/55",
+            pulse: false,
+          }))
+    : null;
+  const sourceTitle = source?.title ?? "source thread";
+
+  return (
+    <div className="group flex flex-col items-start gap-1">
+      <div className="w-fit max-w-[80%] rounded-2xl border border-primary/55 bg-secondary px-3.5 py-3 text-foreground">
+        <div className="mb-2 flex min-w-0 flex-wrap items-center gap-x-1.5 gap-y-1 text-[11px] leading-none">
+          <span className="font-semibold tracking-[0.08em] text-muted-foreground">
+            AGENT MESSAGE
+          </span>
+          <span className="text-muted-foreground/45" aria-hidden="true">
+            ·
+          </span>
+          {status ? <ThreadStatusLabel status={status} compact={compactStatus} /> : null}
+          <button
+            type="button"
+            onClick={() => ctx.onOpenSourceThread(sourceThreadId)}
+            className="inline-flex min-w-0 items-center gap-0.5 rounded-sm font-medium lowercase text-primary hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/70"
+            aria-label={`Open source thread: ${sourceTitle}`}
+          >
+            <span className="truncate">{sourceTitle}</span>
+            <ArrowUpRightIcon className="size-3 shrink-0" aria-hidden="true" />
+          </button>
+          <Tooltip>
+            <TooltipTrigger
+              render={<span className="ms-auto text-muted-foreground tabular-nums" />}
+            >
+              {formatDayAwareTimestamp(row.message.createdAt, ctx.timestampFormat)}
+            </TooltipTrigger>
+            <TooltipPopup>
+              {formatChatTimestampTooltip(row.message.createdAt, ctx.timestampFormat)}
+            </TooltipPopup>
+          </Tooltip>
+        </div>
+        <ChatMarkdown
+          text={row.message.text}
+          cwd={ctx.markdownCwd}
+          threadRef={ctx.threadRef ?? undefined}
+          skills={ctx.skills}
+        />
+      </div>
+    </div>
+  );
+}
+
 function UserTimelineRow({ row }: { row: Extract<TimelineRow, { kind: "message" }> }) {
   const ctx = use(TimelineRowCtx);
   // The attachment union has an open member, so guards (not literal type
diff --git a/docs/user/codex-thread-tools.md b/docs/user/codex-thread-tools.md
index 7815e006fb09..3d15e1a751c1 100644
--- a/docs/user/codex-thread-tools.md
+++ b/docs/user/codex-thread-tools.md
@@ -33,6 +33,10 @@ confirms that LastCode persisted the request, not that the provider finished it.
 oversized messages, missing or ambiguous targets, authorization failures, and rejected dispatches
 fail without reporting acceptance.
 
+Messages sent from one LastCode thread to another appear in the target conversation as agent
+message cards. The card links back to the source thread and shows its current status. A plain
+`send` to the caller's own thread remains a normal user message.
+
 Add `--wait` when the caller needs the exact resulting turn rather than dispatch acceptance.
 `send --wait` cannot target the caller's current thread because that queued turn cannot begin
 until the current command returns; use plain `send` for a self-directed follow-up.
diff --git a/packages/client-runtime/src/state/threadReducer.test.ts b/packages/client-runtime/src/state/threadReducer.test.ts
index c990466fa15e..19f069d0a330 100644
--- a/packages/client-runtime/src/state/threadReducer.test.ts
+++ b/packages/client-runtime/src/state/threadReducer.test.ts
@@ -396,6 +396,7 @@ describe("applyThreadDetailEvent", () => {
           messageId: MessageId.make("msg-1"),
           role: "user",
           text: "Hello, world!",
+          sourceThreadId: ThreadId.make("thread-source"),
           turnId: null,
           streaming: false,
           createdAt: "2026-04-01T06:00:00.000Z",
@@ -407,6 +408,7 @@ describe("applyThreadDetailEvent", () => {
       if (result.kind === "updated") {
         expect(result.thread.messages).toHaveLength(1);
         expect(result.thread.messages[0]?.text).toBe("Hello, world!");
+        expect(result.thread.messages[0]?.sourceThreadId).toBe("thread-source");
       }
     });
 
diff --git a/packages/client-runtime/src/state/threadReducer.ts b/packages/client-runtime/src/state/threadReducer.ts
index fa7e1ce6f37e..c4939da298c5 100644
--- a/packages/client-runtime/src/state/threadReducer.ts
+++ b/packages/client-runtime/src/state/threadReducer.ts
@@ -312,6 +312,9 @@ export function applyThreadDetailEvent(
         ...(event.payload.attachments !== undefined
           ? { attachments: event.payload.attachments }
           : {}),
+        ...(event.payload.sourceThreadId !== undefined
+          ? { sourceThreadId: event.payload.sourceThreadId }
+          : {}),
         turnId: event.payload.turnId,
         streaming: event.payload.streaming,
         createdAt: event.payload.createdAt,
diff --git a/packages/contracts/src/orchestration.test.ts b/packages/contracts/src/orchestration.test.ts
index 2da7acf3a2b3..87d08459af8a 100644
--- a/packages/contracts/src/orchestration.test.ts
+++ b/packages/contracts/src/orchestration.test.ts
@@ -318,6 +318,50 @@ it.effect("decodes thread.turn.start defaults for provider and runtime mode", ()
   }),
 );
 
+it.effect("preserves cross-thread message provenance", () =>
+  Effect.gen(function* () {
+    const sourceThreadId = "thread-source";
+    const command = yield* decodeThreadTurnStartCommand({
+      type: "thread.turn.start",
+      commandId: "cmd-cross-thread",
+      threadId: "thread-target",
+      sourceThreadId,
+      message: {
+        messageId: "msg-cross-thread",
+        role: "user",
+        text: "status update",
+        attachments: [],
+      },
+      createdAt: "2026-01-01T00:00:00.000Z",
+    });
+    const message = yield* decodeOrchestrationMessage({
+      id: "msg-cross-thread",
+      role: "user",
+      text: "status update",
+      sourceThreadId,
+      turnId: null,
+      streaming: false,
+      createdAt: "2026-01-01T00:00:00.000Z",
+      updatedAt: "2026-01-01T00:00:00.000Z",
+    });
+    const payload = yield* decodeThreadMessageSentPayload({
+      threadId: "thread-target",
+      messageId: "msg-cross-thread",
+      role: "user",
+      text: "status update",
+      sourceThreadId,
+      turnId: null,
+      streaming: false,
+      createdAt: "2026-01-01T00:00:00.000Z",
+      updatedAt: "2026-01-01T00:00:00.000Z",
+    });
+
+    assert.strictEqual(command.sourceThreadId, sourceThreadId);
+    assert.strictEqual(message.sourceThreadId, sourceThreadId);
+    assert.strictEqual(payload.sourceThreadId, sourceThreadId);
+  }),
+);
+
 it.effect("accepts inline images, uploaded images, and uploaded files from clients", () =>
   Effect.gen(function* () {
     const command = yield* decodeClientOrchestrationCommand({
diff --git a/packages/contracts/src/orchestration.ts b/packages/contracts/src/orchestration.ts
index d169282fbb9c..22ea1232ef39 100644
--- a/packages/contracts/src/orchestration.ts
+++ b/packages/contracts/src/orchestration.ts
@@ -517,6 +517,7 @@ export const OrchestrationMessage = Schema.Struct({
   role: OrchestrationMessageRole,
   text: Schema.String,
   attachments: Schema.optional(Schema.Array(ChatAttachment)),
+  sourceThreadId: Schema.optional(ThreadId),
   turnId: Schema.NullOr(TurnId),
   streaming: Schema.Boolean,
   createdAt: IsoDateTime,
@@ -1224,6 +1225,7 @@ export const ThreadTurnStartCommand = Schema.Struct({
     Schema.withDecodingDefault(Effect.succeed(DEFAULT_PROVIDER_INTERACTION_MODE)),
   ),
   bootstrap: Schema.optional(ThreadTurnStartBootstrap),
+  sourceThreadId: Schema.optional(ThreadId),
   sourceProposedPlan: Schema.optional(SourceProposedPlanReference),
   trackRequestCorrelation: Schema.optional(Schema.Literal(true)),
   createdAt: IsoDateTime,
@@ -1244,6 +1246,7 @@ const ClientThreadTurnStartCommand = Schema.Struct({
   runtimeMode: RuntimeMode,
   interactionMode: ProviderInteractionMode,
   bootstrap: Schema.optional(ThreadTurnStartBootstrap),
+  sourceThreadId: Schema.optional(ThreadId),
   sourceProposedPlan: Schema.optional(SourceProposedPlanReference),
   trackRequestCorrelation: Schema.optional(Schema.Literal(true)),
   createdAt: IsoDateTime,
@@ -1691,6 +1694,7 @@ export const ThreadMessageSentPayload = Schema.Struct({
   role: OrchestrationMessageRole,
   text: Schema.String,
   attachments: Schema.optional(Schema.Array(ChatAttachment)),
+  sourceThreadId: Schema.optional(ThreadId),
   turnId: Schema.NullOr(TurnId),
   streaming: Schema.Boolean,
   createdAt: IsoDateTime,

From ea7be2e4d69fb6b746abb932d7485e9db8f1a897 Mon Sep 17 00:00:00 2001
From: Michael Johnston <lastobelus@mac.com>
Date: Sun, 30 Aug 2026 14:10:49 -0700
Subject: [PATCH 2/5] fix(chat): complete cross-thread agent cards

---
 .../src/features/threads/ThreadFeed.tsx       | 145 ++++++++++++++++++
 .../components/chat/MessagesTimeline.test.tsx |  55 +++++--
 .../src/components/chat/MessagesTimeline.tsx  |  24 +--
 3 files changed, 202 insertions(+), 22 deletions(-)

diff --git a/apps/mobile/src/features/threads/ThreadFeed.tsx b/apps/mobile/src/features/threads/ThreadFeed.tsx
index 607c32920464..7142e22da5c1 100644
--- a/apps/mobile/src/features/threads/ThreadFeed.tsx
+++ b/apps/mobile/src/features/threads/ThreadFeed.tsx
@@ -3,6 +3,7 @@ import { KeyboardAwareLegendList } from "@legendapp/list/keyboard";
 import { type LegendListRef } from "@legendapp/list/react-native";
 import type { EnvironmentId, MessageId, ThreadId, TurnId } from "@t3tools/contracts";
 import { classifyMarkdownImageSource } from "@t3tools/client-runtime/markdown-images";
+import { scopeThreadRef } from "@t3tools/client-runtime/environment";
 import { CHAT_LIST_ANCHOR_OFFSET, resolveChatListAnchoredEndSpace } from "@t3tools/shared/chatList";
 import {
   actionResultPresentation,
@@ -114,8 +115,10 @@ import {
 } from "./thread-work-log";
 import { useMarkdownCodeHighlight } from "./markdownCodeHighlightState";
 import { useAssetUrl, useAssetUrlState } from "../../state/assets";
+import { useThreadShell } from "../../state/entities";
 import { resolveWorkspaceRelativeFilePath } from "../files/filePath";
 import { MARKDOWN_IMAGE_MAX_WIDTH, resolveMarkdownImageDisplaySize } from "./markdownImageSize";
+import { resolveThreadStatus } from "./threadPresentation";
 
 const WIDE_MARKDOWN_BLOCK_OPTIONS = {
   includeOrderedLists: Platform.OS === "android",
@@ -980,6 +983,7 @@ function renderFeedEntry(
     readonly onToggleActionFollowUp: (rowId: string) => void;
     readonly onPressImage: (uri: string, headers?: Record<string, string>) => void;
     readonly onMarkdownLinkPress: (href: string) => void;
+    readonly onOpenSourceThread: (sourceThreadId: ThreadId) => void;
     readonly renderMarkdownImage: MarkdownImageRenderer;
     readonly iconSubtleColor: string | import("react-native").ColorValue;
     readonly userBubbleColor: string | import("react-native").ColorValue;
@@ -1074,6 +1078,25 @@ function renderFeedEntry(
       !assistantTurnStillInProgress &&
       !message.streaming;
 
+    if (isUser && message.sourceThreadId !== undefined) {
+      return (
+        <AgentMessageTimelineRow
+          entry={entry}
+          environmentId={props.environmentId}
+          iconSubtleColor={iconSubtleColor}
+          markdownStyles={markdownStyles.assistant}
+          maxWidth={props.userBubbleMaxWidth}
+          onLinkPress={props.onMarkdownLinkPress}
+          onOpenSourceThread={props.onOpenSourceThread}
+          onPressImage={props.onPressImage}
+          renderImage={props.renderMarkdownImage}
+          reviewCommentColors={props.reviewCommentColors}
+          skills={props.skills}
+          sourceThreadId={message.sourceThreadId}
+        />
+      );
+    }
+
     if (isUser) {
       const enterAnimated = isFreshTimestamp(message.createdAt);
       return (
@@ -1206,6 +1229,117 @@ function renderFeedEntry(
   );
 }
 
+function AgentMessageTimelineRow(props: {
+  readonly entry: Extract<ThreadFeedEntry, { type: "message" }>;
+  readonly environmentId: EnvironmentId;
+  readonly iconSubtleColor: ColorValue;
+  readonly markdownStyles: MarkdownStyleSet;
+  readonly maxWidth: number;
+  readonly onLinkPress: (href: string) => void;
+  readonly onOpenSourceThread: (sourceThreadId: ThreadId) => void;
+  readonly onPressImage: (uri: string, headers?: Record<string, string>) => void;
+  readonly renderImage: MarkdownImageRenderer;
+  readonly reviewCommentColors: ReviewCommentColors;
+  readonly skills?: ReadonlyArray<SelectableMarkdownSkill>;
+  readonly sourceThreadId: ThreadId;
+}) {
+  const source = useThreadShell(scopeThreadRef(props.environmentId, props.sourceThreadId));
+  const resolvedStatus = source ? resolveThreadStatus(source) : null;
+  const status = source
+    ? (resolvedStatus ?? {
+        label: "Ready",
+        iconColor: props.iconSubtleColor,
+      })
+    : null;
+  const sourceTitle = source?.title ?? "Source thread unavailable";
+  const message = props.entry.message;
+  const attachments = (message.attachments ?? []).filter(
+    (attachment) => attachment.type === "image",
+  );
+
+  return (
+    <Animated.View
+      className="mb-5 items-start"
+      {...(isFreshTimestamp(message.createdAt) ? { entering: FadeInUp.duration(220) } : {})}
+    >
+      <View
+        className="min-w-0 gap-2 rounded-[20px] border border-primary bg-secondary px-3.5 py-3"
+        style={{ maxWidth: props.maxWidth }}
+      >
+        <View className="min-w-0 flex-row flex-wrap items-center gap-1.5">
+          <Text className="font-t3-bold text-2xs tracking-wider text-foreground-muted">
+            AGENT MESSAGE
+          </Text>
+          {status ? (
+            <View className="flex-row items-center gap-1">
+              <View
+                className="h-1.5 w-1.5 rounded-full"
+                style={{ backgroundColor: status.iconColor }}
+              />
+              <Text className="font-t3-medium text-2xs text-foreground-muted">{status.label}</Text>
+            </View>
+          ) : null}
+          {source ? (
+            <Pressable
+              accessibilityRole="button"
+              accessibilityLabel={`Open source thread: ${source.title}`}
+              className="min-w-0 flex-row items-center gap-0.5 active:opacity-60"
+              onPress={() => props.onOpenSourceThread(props.sourceThreadId)}
+            >
+              <Text className="shrink font-t3-medium text-2xs text-primary" numberOfLines={1}>
+                {sourceTitle.toLocaleLowerCase()}
+              </Text>
+              <SymbolView
+                name="arrow.up.right"
+                size={11}
+                tintColorClassName="accent-icon-subtle"
+                type="monochrome"
+              />
+            </Pressable>
+          ) : (
+            <Text className="shrink font-t3-medium text-2xs text-foreground-muted">
+              {sourceTitle.toLocaleLowerCase()}
+            </Text>
+          )}
+          <Text className="ml-auto font-t3-medium text-2xs tabular-nums text-foreground-muted">
+            {formatMessageTime(message.createdAt)}
+          </Text>
+        </View>
+        {message.text.trim().length > 0 ? (
+          <UserMessageContent
+            text={message.text}
+            markdownStyles={props.markdownStyles}
+            reviewCommentColors={props.reviewCommentColors}
+            skills={props.skills}
+            onLinkPress={props.onLinkPress}
+            renderImage={props.renderImage}
+          />
+        ) : null}
+        {attachments.map((attachment) => (
+          <MessageAttachmentImage
+            key={attachment.id}
+            environmentId={props.environmentId}
+            attachmentId={attachment.id}
+            className="aspect-[1.3] w-full rounded-[14px] bg-white/15"
+            onPressImage={props.onPressImage}
+          />
+        ))}
+      </View>
+      {message.text.trim().length > 0 ? (
+        <View className="mt-1 pl-0.5">
+          <CopyTextButton
+            accessibilityLabel="Copy agent message"
+            text={message.text}
+            tintColor={props.iconSubtleColor}
+            buttonSize={28}
+            iconSize={13}
+          />
+        </View>
+      ) : null}
+    </Animated.View>
+  );
+}
+
 const ActionFollowUpCard = memo(function ActionFollowUpCard(props: {
   readonly actionName: string;
   readonly outcome: ActionResultPresentationOutcome;
@@ -1731,6 +1865,15 @@ export const ThreadFeed = memo(function ThreadFeed(props: ThreadFeedProps) {
     },
     [props.environmentId, props.threadId, props.workspaceRoot, navigation],
   );
+  const onOpenSourceThread = useCallback(
+    (sourceThreadId: ThreadId) => {
+      navigation.navigate("Thread", {
+        environmentId: String(props.environmentId),
+        threadId: String(sourceThreadId),
+      });
+    },
+    [navigation, props.environmentId],
+  );
   const renderMarkdownImage = useCallback<MarkdownImageRenderer>(
     (image) => {
       const imageSource = classifyMarkdownImageSource(image.href, props.workspaceRoot ?? null);
@@ -2167,6 +2310,7 @@ export const ThreadFeed = memo(function ThreadFeed(props: ThreadFeedProps) {
         onToggleActionFollowUp,
         onPressImage,
         onMarkdownLinkPress,
+        onOpenSourceThread,
         renderMarkdownImage,
         iconSubtleColor,
         userBubbleColor,
@@ -2190,6 +2334,7 @@ export const ThreadFeed = memo(function ThreadFeed(props: ThreadFeedProps) {
       userBubbleMaxWidth,
       onCopyWorkRow,
       onMarkdownLinkPress,
+      onOpenSourceThread,
       onPressImage,
       onToggleTurnFold,
       onToggleActionFollowUp,
diff --git a/apps/web/src/components/chat/MessagesTimeline.test.tsx b/apps/web/src/components/chat/MessagesTimeline.test.tsx
index eb927fc800cc..9eb02916f487 100644
--- a/apps/web/src/components/chat/MessagesTimeline.test.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.test.tsx
@@ -6,6 +6,8 @@ import { renderToStaticMarkup } from "react-dom/server";
 import { beforeAll, describe, expect, it, vi } from "vite-plus/test";
 import type { LegendListRef } from "@legendapp/list/react";
 
+const threadShellMockState = vi.hoisted(() => ({ available: true }));
+
 vi.mock("@legendapp/list/react", async () => {
   const legendListTestId = "legend-list";
 
@@ -131,19 +133,22 @@ vi.mock("../../state/entities", async (importOriginal) => {
   const actual = await importOriginal<typeof import("../../state/entities")>();
   return {
     ...actual,
-    useThreadShell: () => ({
-      id: ThreadId.make("thread-source"),
-      title: "Mobile Reconnect Issue",
-      hasActionableProposedPlan: false,
-      hasPendingApprovals: false,
-      hasPendingUserInput: false,
-      interactionMode: "default",
-      latestTurn: null,
-      session: { status: "running" },
-      backgroundLiveness: null,
-      actionResume: null,
-      worktreeCleanup: null,
-    }),
+    useThreadShell: () =>
+      threadShellMockState.available
+        ? {
+            id: ThreadId.make("thread-source"),
+            title: "Mobile Reconnect Issue",
+            hasActionableProposedPlan: false,
+            hasPendingApprovals: false,
+            hasPendingUserInput: false,
+            interactionMode: "default",
+            latestTurn: null,
+            session: { status: "running" },
+            backgroundLiveness: null,
+            actionResume: null,
+            worktreeCleanup: null,
+          }
+        : null,
   };
 });
 
@@ -285,6 +290,30 @@ describe("MessagesTimeline", () => {
     expect(markup).not.toContain("bg-message p-3");
   });
 
+  it("does not link to a source thread that is no longer available", () => {
+    threadShellMockState.available = false;
+    try {
+      const sourceThreadId = ThreadId.make("thread-source");
+      const entry = buildUserTimelineEntry("The reconnect fix is ready for review.");
+      const markup = renderToStaticMarkup(
+        <MessagesTimeline
+          {...buildProps()}
+          timelineEntries={[
+            {
+              ...entry,
+              message: { ...entry.message, sourceThreadId },
+            },
+          ]}
+        />,
+      );
+
+      expect(markup).toContain("source thread unavailable");
+      expect(markup).not.toContain("Open source thread:");
+    } finally {
+      threadShellMockState.available = true;
+    }
+  });
+
   it("shows compact completed Action results without embedding detailed output", () => {
     const actionText = formatActionResumeFollowUp({
       actionName: "Run Full CI",
diff --git a/apps/web/src/components/chat/MessagesTimeline.tsx b/apps/web/src/components/chat/MessagesTimeline.tsx
index b8d69c8c8e95..7f0537358a40 100644
--- a/apps/web/src/components/chat/MessagesTimeline.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.tsx
@@ -1282,15 +1282,21 @@ function AgentMessageTimelineRow({
             ·
           </span>
           {status ? <ThreadStatusLabel status={status} compact={compactStatus} /> : null}
-          <button
-            type="button"
-            onClick={() => ctx.onOpenSourceThread(sourceThreadId)}
-            className="inline-flex min-w-0 items-center gap-0.5 rounded-sm font-medium lowercase text-primary hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/70"
-            aria-label={`Open source thread: ${sourceTitle}`}
-          >
-            <span className="truncate">{sourceTitle}</span>
-            <ArrowUpRightIcon className="size-3 shrink-0" aria-hidden="true" />
-          </button>
+          {source ? (
+            <button
+              type="button"
+              onClick={() => ctx.onOpenSourceThread(sourceThreadId)}
+              className="inline-flex min-w-0 items-center gap-0.5 rounded-sm font-medium lowercase text-primary hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/70"
+              aria-label={`Open source thread: ${sourceTitle}`}
+            >
+              <span className="truncate">{sourceTitle}</span>
+              <ArrowUpRightIcon className="size-3 shrink-0" aria-hidden="true" />
+            </button>
+          ) : (
+            <span className="min-w-0 truncate font-medium lowercase text-muted-foreground">
+              source thread unavailable
+            </span>
+          )}
           <Tooltip>
             <TooltipTrigger
               render={<span className="ms-auto text-muted-foreground tabular-nums" />}

From 2fcc91b73a82773be151233c646ebce3fb5ef73b Mon Sep 17 00:00:00 2001
From: Michael Johnston <lastobelus@mac.com>
Date: Sun, 30 Aug 2026 14:20:17 -0700
Subject: [PATCH 3/5] fix(web): preserve agent message interactions

---
 .../components/chat/MessagesTimeline.test.tsx |  42 ++-
 .../src/components/chat/MessagesTimeline.tsx  | 244 +++++++++++-------
 2 files changed, 177 insertions(+), 109 deletions(-)

diff --git a/apps/web/src/components/chat/MessagesTimeline.test.tsx b/apps/web/src/components/chat/MessagesTimeline.test.tsx
index 9eb02916f487..50793c837884 100644
--- a/apps/web/src/components/chat/MessagesTimeline.test.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.test.tsx
@@ -161,6 +161,7 @@ function matchMedia() {
 }
 
 let MessagesTimeline: typeof import("./MessagesTimeline").MessagesTimeline;
+let AgentMessageSourceTitle: typeof import("./MessagesTimeline").AgentMessageSourceTitle;
 
 beforeAll(async () => {
   const classList = {
@@ -194,7 +195,7 @@ beforeAll(async () => {
     },
   });
 
-  ({ MessagesTimeline } = await import("./MessagesTimeline"));
+  ({ MessagesTimeline, AgentMessageSourceTitle } = await import("./MessagesTimeline"));
 }, 30_000);
 
 const ACTIVE_THREAD_ENVIRONMENT_ID = EnvironmentId.make("environment-local");
@@ -263,7 +264,7 @@ function buildAssistantTimelineEntry(text: string) {
 }
 
 describe("MessagesTimeline", () => {
-  it("renders cross-thread posts as left-aligned agent message cards", () => {
+  it("renders cross-thread posts as agent messages with their attachments", () => {
     const sourceThreadId = ThreadId.make("thread-source");
     const entry = buildUserTimelineEntry("The reconnect fix is ready for review.");
     const markup = renderToStaticMarkup(
@@ -272,7 +273,20 @@ describe("MessagesTimeline", () => {
         timelineEntries={[
           {
             ...entry,
-            message: { ...entry.message, sourceThreadId },
+            message: {
+              ...entry.message,
+              sourceThreadId,
+              attachments: [
+                {
+                  type: "file" as const,
+                  id: "attachment-report-pdf",
+                  name: "handoff.pdf",
+                  mimeType: "application/pdf",
+                  sizeBytes: 42,
+                  previewUrl: "https://environment.test/api/assets/handoff.pdf",
+                },
+              ],
+            },
           },
         ]}
       />,
@@ -281,13 +295,23 @@ describe("MessagesTimeline", () => {
     expect(markup).toContain("AGENT MESSAGE");
     expect(markup).toContain("Mobile Reconnect Issue");
     expect(markup).toContain("Working");
-    expect(markup).toContain("items-start");
-    expect(markup).toContain("max-w-[80%]");
-    expect(markup).toContain("border-primary/55 bg-secondary");
-    expect(markup).toContain("font-medium lowercase text-primary");
     expect(markup).toContain('aria-label="Open source thread: Mobile Reconnect Issue"');
-    expect(markup).not.toContain("Open source thread</a>");
-    expect(markup).not.toContain("bg-message p-3");
+    expect(markup).toContain('download="handoff.pdf"');
+  });
+
+  it("opens the source thread when its title is activated", () => {
+    const sourceThreadId = ThreadId.make("thread-source");
+    const onOpenSourceThread = vi.fn();
+    const sourceTitle = AgentMessageSourceTitle({
+      sourceThreadId,
+      sourceTitle: "Mobile Reconnect Issue",
+      onOpenSourceThread,
+    });
+
+    expect(sourceTitle.type).toBe("button");
+    sourceTitle.props.onClick?.();
+    expect(onOpenSourceThread).toHaveBeenCalledOnce();
+    expect(onOpenSourceThread).toHaveBeenCalledWith(sourceThreadId);
   });
 
   it("does not link to a source thread that is no longer available", () => {
diff --git a/apps/web/src/components/chat/MessagesTimeline.tsx b/apps/web/src/components/chat/MessagesTimeline.tsx
index 7f0537358a40..4a83966f856d 100644
--- a/apps/web/src/components/chat/MessagesTimeline.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.tsx
@@ -45,6 +45,8 @@ import {
   workLogEntryIsToolLike,
 } from "../../session-logic";
 import {
+  type ChatAttachment,
+  type ChatFileAttachment as WebChatFileAttachment,
   type ChatImageAttachment,
   isFileAttachment,
   isImageAttachment,
@@ -1270,6 +1272,11 @@ function AgentMessageTimelineRow({
           }))
     : null;
   const sourceTitle = source?.title ?? "source thread";
+  const images = (row.message.attachments ?? []).filter(isImageAttachment);
+  const files = (row.message.attachments ?? []).filter(isFileAttachment);
+  const unknownAttachments = (row.message.attachments ?? []).filter(
+    (attachment) => !isImageAttachment(attachment) && !isFileAttachment(attachment),
+  );
 
   return (
     <div className="group flex flex-col items-start gap-1">
@@ -1282,21 +1289,11 @@ function AgentMessageTimelineRow({
             ·
           </span>
           {status ? <ThreadStatusLabel status={status} compact={compactStatus} /> : null}
-          {source ? (
-            <button
-              type="button"
-              onClick={() => ctx.onOpenSourceThread(sourceThreadId)}
-              className="inline-flex min-w-0 items-center gap-0.5 rounded-sm font-medium lowercase text-primary hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/70"
-              aria-label={`Open source thread: ${sourceTitle}`}
-            >
-              <span className="truncate">{sourceTitle}</span>
-              <ArrowUpRightIcon className="size-3 shrink-0" aria-hidden="true" />
-            </button>
-          ) : (
-            <span className="min-w-0 truncate font-medium lowercase text-muted-foreground">
-              source thread unavailable
-            </span>
-          )}
+          <AgentMessageSourceTitle
+            sourceThreadId={sourceThreadId}
+            sourceTitle={source ? sourceTitle : null}
+            onOpenSourceThread={ctx.onOpenSourceThread}
+          />
           <Tooltip>
             <TooltipTrigger
               render={<span className="ms-auto text-muted-foreground tabular-nums" />}
@@ -1308,6 +1305,7 @@ function AgentMessageTimelineRow({
             </TooltipPopup>
           </Tooltip>
         </div>
+        <MessageAttachments images={images} files={files} unknown={unknownAttachments} />
         <ChatMarkdown
           text={row.message.text}
           cwd={ctx.markdownCwd}
@@ -1319,6 +1317,128 @@ function AgentMessageTimelineRow({
   );
 }
 
+export function AgentMessageSourceTitle({
+  sourceThreadId,
+  sourceTitle,
+  onOpenSourceThread,
+}: {
+  sourceThreadId: ThreadId;
+  sourceTitle: string | null;
+  onOpenSourceThread: (threadId: ThreadId) => void;
+}) {
+  return sourceTitle ? (
+    <button
+      type="button"
+      onClick={() => onOpenSourceThread(sourceThreadId)}
+      className="inline-flex min-w-0 items-center gap-0.5 rounded-sm font-medium lowercase text-primary hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-ring/70"
+      aria-label={`Open source thread: ${sourceTitle}`}
+    >
+      <span className="truncate">{sourceTitle}</span>
+      <ArrowUpRightIcon className="size-3 shrink-0" aria-hidden="true" />
+    </button>
+  ) : (
+    <span className="min-w-0 truncate font-medium lowercase text-muted-foreground">
+      source thread unavailable
+    </span>
+  );
+}
+
+function MessageAttachments({
+  images,
+  files,
+  unknown,
+  children,
+}: {
+  images: ReadonlyArray<ChatImageAttachment>;
+  files: ReadonlyArray<WebChatFileAttachment>;
+  unknown: ReadonlyArray<ChatAttachment>;
+  children?: ReactNode;
+}) {
+  const ctx = use(TimelineRowCtx);
+
+  return (
+    <>
+      {images.length > 0 ? (
+        <div className="mb-2 grid max-w-[420px] grid-cols-2 gap-2">
+          {images.map((image) => (
+            <div
+              key={image.id}
+              className="overflow-hidden rounded-lg border border-border/80 bg-background/70"
+            >
+              {image.previewUrl ? (
+                <button
+                  type="button"
+                  className="h-full w-full cursor-zoom-in"
+                  aria-label={`Preview ${image.name}`}
+                  onClick={() => {
+                    const preview = buildExpandedImagePreview(images, image.id);
+                    if (!preview) return;
+                    ctx.onImageExpand(preview);
+                  }}
+                >
+                  <img
+                    src={image.previewUrl}
+                    alt={image.name}
+                    className="block h-auto max-h-[220px] w-full object-cover"
+                  />
+                </button>
+              ) : (
+                <div className="flex min-h-[72px] items-center justify-center px-2 py-3 text-center text-secondary-label text-[11px]">
+                  {image.name}
+                </div>
+              )}
+            </div>
+          ))}
+        </div>
+      ) : null}
+      {children}
+      {files.length > 0 || unknown.length > 0 ? (
+        <div className="mb-2 flex flex-col gap-1">
+          {files.map((file) => {
+            const content = (
+              <>
+                <FileIcon className="size-4 shrink-0 text-secondary-label" />
+                <span className="min-w-0 flex-1 truncate">{file.name}</span>
+                {file.downloadable === false ? null : <DownloadIcon className="size-4 shrink-0" />}
+              </>
+            );
+            return file.previewUrl ? (
+              <a
+                key={file.id}
+                href={file.previewUrl}
+                download={file.name}
+                className="flex min-w-0 items-center gap-2 rounded-md py-1 text-sm hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/70"
+              >
+                {content}
+              </a>
+            ) : file.downloadable === false ? (
+              <div key={file.id} className="flex min-w-0 items-center gap-2 py-1 text-sm">
+                {content}
+              </div>
+            ) : (
+              <button
+                key={file.id}
+                type="button"
+                aria-label={`Download ${file.name}`}
+                onClick={() => ctx.onFileDownload(file)}
+                className="flex min-w-0 cursor-pointer items-center gap-2 rounded-md py-1 text-left text-sm hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/70"
+              >
+                {content}
+              </button>
+            );
+          })}
+          {unknown.map((attachment) => (
+            <div key={attachment.id} className="flex min-w-0 items-center gap-2 py-1 text-sm">
+              <FileIcon className="size-4 shrink-0 text-secondary-label" />
+              <span className="min-w-0 flex-1 truncate">{attachment.name}</span>
+            </div>
+          ))}
+        </div>
+      ) : null}
+    </>
+  );
+}
+
 function UserTimelineRow({ row }: { row: Extract<TimelineRow, { kind: "message" }> }) {
   const ctx = use(TimelineRowCtx);
   // The attachment union has an open member, so guards (not literal type
@@ -1350,91 +1470,15 @@ function UserTimelineRow({ row }: { row: Extract<TimelineRow, { kind: "message"
   return (
     <div className="group flex flex-col items-end gap-1">
       <div className="relative max-w-[80%] rounded-2xl bg-message p-3 text-message-foreground">
-        {regularImages.length > 0 && (
-          <div className="mb-2 grid max-w-[420px] grid-cols-2 gap-2">
-            {regularImages.map((image) => (
-              <div
-                key={image.id}
-                className="overflow-hidden rounded-lg border border-border/80 bg-background/70"
-              >
-                {image.previewUrl ? (
-                  <button
-                    type="button"
-                    className="h-full w-full cursor-zoom-in"
-                    aria-label={`Preview ${image.name}`}
-                    onClick={() => {
-                      const preview = buildExpandedImagePreview(regularImages, image.id);
-                      if (!preview) return;
-                      ctx.onImageExpand(preview);
-                    }}
-                  >
-                    <img
-                      src={image.previewUrl}
-                      alt={image.name}
-                      className="block h-auto max-h-[220px] w-full object-cover"
-                    />
-                  </button>
-                ) : (
-                  <div className="flex min-h-[72px] items-center justify-center px-2 py-3 text-center text-secondary-label text-[11px]">
-                    {image.name}
-                  </div>
-                )}
-              </div>
-            ))}
-          </div>
-        )}
-        {previewAnnotations.map((annotation, index) => (
-          <UserMessagePreviewAnnotationCard
-            key={annotation.id}
-            annotation={annotation}
-            image={previewImages[index] ?? null}
-          />
-        ))}
-        {userFiles.length > 0 || unknownAttachments.length > 0 ? (
-          <div className="mb-2 flex flex-col gap-1">
-            {userFiles.map((file) => {
-              const content = (
-                <>
-                  <FileIcon className="size-4 shrink-0 text-secondary-label" />
-                  <span className="min-w-0 flex-1 truncate">{file.name}</span>
-                  {file.downloadable === false ? null : (
-                    <DownloadIcon className="size-4 shrink-0" />
-                  )}
-                </>
-              );
-              return file.previewUrl ? (
-                <a
-                  key={file.id}
-                  href={file.previewUrl}
-                  download={file.name}
-                  className="flex min-w-0 items-center gap-2 rounded-md py-1 text-sm hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/70"
-                >
-                  {content}
-                </a>
-              ) : file.downloadable === false ? (
-                <div key={file.id} className="flex min-w-0 items-center gap-2 py-1 text-sm">
-                  {content}
-                </div>
-              ) : (
-                <button
-                  key={file.id}
-                  type="button"
-                  aria-label={`Download ${file.name}`}
-                  onClick={() => ctx.onFileDownload(file)}
-                  className="flex min-w-0 cursor-pointer items-center gap-2 rounded-md py-1 text-left text-sm hover:underline focus-visible:outline-none focus-visible:ring-2 focus-visible:ring-inset focus-visible:ring-ring/70"
-                >
-                  {content}
-                </button>
-              );
-            })}
-            {unknownAttachments.map((attachment) => (
-              <div key={attachment.id} className="flex min-w-0 items-center gap-2 py-1 text-sm">
-                <FileIcon className="size-4 shrink-0 text-secondary-label" />
-                <span className="min-w-0 flex-1 truncate">{attachment.name}</span>
-              </div>
-            ))}
-          </div>
-        ) : null}
+        <MessageAttachments images={regularImages} files={userFiles} unknown={unknownAttachments}>
+          {previewAnnotations.map((annotation, index) => (
+            <UserMessagePreviewAnnotationCard
+              key={annotation.id}
+              annotation={annotation}
+              image={previewImages[index] ?? null}
+            />
+          ))}
+        </MessageAttachments>
         {elementContexts.length > 0 ? (
           <div className="mb-2 flex flex-wrap gap-1.5">
             {elementContexts.map((context) => (

From 63e286bc166d3e4af97df63ad3368eab06201598 Mon Sep 17 00:00:00 2001
From: Michael Johnston <lastobelus@mac.com>
Date: Sun, 30 Aug 2026 14:34:01 -0700
Subject: [PATCH 4/5] test(web): mount agent message navigation

---
 apps/web/package.json                         |   1 +
 apps/web/src/components/ChatView.tsx          |  11 +-
 .../components/chat/MessagesTimeline.test.tsx | 107 +++++++++++++++---
 .../src/components/chat/MessagesTimeline.tsx  |   2 +-
 apps/web/src/threadRoutes.ts                  |  10 ++
 pnpm-lock.yaml                                |  96 ++++++++++++----
 6 files changed, 182 insertions(+), 45 deletions(-)

diff --git a/apps/web/package.json b/apps/web/package.json
index 2e0d334934be..e285634cd091 100644
--- a/apps/web/package.json
+++ b/apps/web/package.json
@@ -65,6 +65,7 @@
     "@vitejs/plugin-react": "^6.0.0",
     "babel-plugin-react-compiler": "1.0.0",
     "compression": "^1.8.1",
+    "happy-dom": "^20.12.0",
     "msw": "2.12.11",
     "tailwindcss": "^4.0.0",
     "vite": "catalog:",
diff --git a/apps/web/src/components/ChatView.tsx b/apps/web/src/components/ChatView.tsx
index aeaff1d20cdc..3a90a6584530 100644
--- a/apps/web/src/components/ChatView.tsx
+++ b/apps/web/src/components/ChatView.tsx
@@ -230,7 +230,11 @@ import {
   selectProjectGroupingSettings,
 } from "../logicalProject";
 import { buildPhysicalToLogicalProjectKeyMap } from "../sidebarProjectGrouping";
-import { buildDraftThreadRouteParams, buildThreadRouteParams } from "../threadRoutes";
+import {
+  buildDraftThreadRouteParams,
+  buildThreadRouteLocation,
+  buildThreadRouteParams,
+} from "../threadRoutes";
 import {
   beginBackgroundDraftSubmissionByRef,
   clearBackgroundDraftSubmissionByRef,
@@ -1866,10 +1870,7 @@ function ChatViewContent(props: ChatViewProps) {
   const openAgentMessageSourceThread = useCallback(
     (threadId: ThreadId) => {
       if (!activeThread) return;
-      void navigate({
-        to: "/$environmentId/$threadId",
-        params: buildThreadRouteParams(scopeThreadRef(activeThread.environmentId, threadId)),
-      });
+      void navigate(buildThreadRouteLocation(scopeThreadRef(activeThread.environmentId, threadId)));
     },
     [activeThread, navigate],
   );
diff --git a/apps/web/src/components/chat/MessagesTimeline.test.tsx b/apps/web/src/components/chat/MessagesTimeline.test.tsx
index 50793c837884..df844d83f83b 100644
--- a/apps/web/src/components/chat/MessagesTimeline.test.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.test.tsx
@@ -1,10 +1,14 @@
 import { CheckpointRef, EnvironmentId, MessageId, ThreadId, TurnId } from "@t3tools/contracts";
 import { codexFeedbackMessage } from "@t3tools/client-runtime/state/threads";
+import { scopeThreadRef } from "@t3tools/client-runtime/environment";
 import { formatActionResumeFollowUp } from "@t3tools/shared/actionResume";
-import { createRef, type ReactNode, type Ref } from "react";
+import { act, createRef, type ReactNode, type Ref } from "react";
+import { createRoot } from "react-dom/client";
 import { renderToStaticMarkup } from "react-dom/server";
 import { beforeAll, describe, expect, it, vi } from "vite-plus/test";
 import type { LegendListRef } from "@legendapp/list/react";
+import { Window } from "happy-dom";
+import { buildThreadRouteLocation } from "../../threadRoutes";
 
 const threadShellMockState = vi.hoisted(() => ({ available: true }));
 
@@ -160,8 +164,46 @@ function matchMedia() {
   };
 }
 
+function installBrowserGlobals(browser: Window) {
+  const values = {
+    window: browser,
+    document: browser.document,
+    navigator: browser.navigator,
+    Node: browser.Node,
+    Element: browser.Element,
+    HTMLElement: browser.HTMLElement,
+    HTMLIFrameElement: browser.HTMLIFrameElement,
+    Event: browser.Event,
+    MouseEvent: browser.MouseEvent,
+    MutationObserver: browser.MutationObserver,
+    ResizeObserver: browser.ResizeObserver,
+    getComputedStyle: browser.getComputedStyle.bind(browser),
+    requestAnimationFrame: browser.requestAnimationFrame.bind(browser),
+    cancelAnimationFrame: browser.cancelAnimationFrame.bind(browser),
+    IS_REACT_ACT_ENVIRONMENT: true,
+  } as const;
+  const descriptors = new Map(
+    Object.keys(values).map((key) => [key, Object.getOwnPropertyDescriptor(globalThis, key)]),
+  );
+
+  for (const [key, value] of Object.entries(values)) {
+    Object.defineProperty(globalThis, key, { configurable: true, writable: true, value });
+  }
+
+  return {
+    restore() {
+      for (const [key, descriptor] of descriptors) {
+        if (descriptor) {
+          Object.defineProperty(globalThis, key, descriptor);
+        } else {
+          Reflect.deleteProperty(globalThis, key);
+        }
+      }
+    },
+  };
+}
+
 let MessagesTimeline: typeof import("./MessagesTimeline").MessagesTimeline;
-let AgentMessageSourceTitle: typeof import("./MessagesTimeline").AgentMessageSourceTitle;
 
 beforeAll(async () => {
   const classList = {
@@ -195,7 +237,7 @@ beforeAll(async () => {
     },
   });
 
-  ({ MessagesTimeline, AgentMessageSourceTitle } = await import("./MessagesTimeline"));
+  ({ MessagesTimeline } = await import("./MessagesTimeline"));
 }, 30_000);
 
 const ACTIVE_THREAD_ENVIRONMENT_ID = EnvironmentId.make("environment-local");
@@ -299,19 +341,56 @@ describe("MessagesTimeline", () => {
     expect(markup).toContain('download="handoff.pdf"');
   });
 
-  it("opens the source thread when its title is activated", () => {
+  it("navigates to the source thread when the rendered title is activated", async () => {
     const sourceThreadId = ThreadId.make("thread-source");
-    const onOpenSourceThread = vi.fn();
-    const sourceTitle = AgentMessageSourceTitle({
-      sourceThreadId,
-      sourceTitle: "Mobile Reconnect Issue",
-      onOpenSourceThread,
-    });
+    const entry = buildUserTimelineEntry("The reconnect fix is ready for review.");
+    const navigate = vi.fn();
+    const browser = new Window({ url: "https://lastcode.test" });
+    const globals = installBrowserGlobals(browser);
+    const container = browser.document.createElement("div");
+    browser.document.body.append(container);
+    const root = createRoot(container as unknown as Element);
+
+    try {
+      await act(() => {
+        root.render(
+          <MessagesTimeline
+            {...buildProps()}
+            onOpenSourceThread={(threadId) => {
+              navigate(
+                buildThreadRouteLocation(scopeThreadRef(ACTIVE_THREAD_ENVIRONMENT_ID, threadId)),
+              );
+            }}
+            timelineEntries={[
+              {
+                ...entry,
+                message: { ...entry.message, sourceThreadId },
+              },
+            ]}
+          />,
+        );
+      });
 
-    expect(sourceTitle.type).toBe("button");
-    sourceTitle.props.onClick?.();
-    expect(onOpenSourceThread).toHaveBeenCalledOnce();
-    expect(onOpenSourceThread).toHaveBeenCalledWith(sourceThreadId);
+      const sourceLink = container.querySelector(
+        'button[aria-label="Open source thread: Mobile Reconnect Issue"]',
+      );
+      expect(sourceLink).not.toBeNull();
+      await act(() =>
+        sourceLink?.dispatchEvent(new browser.MouseEvent("click", { bubbles: true })),
+      );
+      expect(navigate).toHaveBeenCalledOnce();
+      expect(navigate).toHaveBeenCalledWith({
+        to: "/$environmentId/$threadId",
+        params: {
+          environmentId: ACTIVE_THREAD_ENVIRONMENT_ID,
+          threadId: sourceThreadId,
+        },
+      });
+    } finally {
+      await act(() => root.unmount());
+      globals.restore();
+      await browser.close();
+    }
   });
 
   it("does not link to a source thread that is no longer available", () => {
diff --git a/apps/web/src/components/chat/MessagesTimeline.tsx b/apps/web/src/components/chat/MessagesTimeline.tsx
index 4a83966f856d..ae4ea9a3bd80 100644
--- a/apps/web/src/components/chat/MessagesTimeline.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.tsx
@@ -1317,7 +1317,7 @@ function AgentMessageTimelineRow({
   );
 }
 
-export function AgentMessageSourceTitle({
+function AgentMessageSourceTitle({
   sourceThreadId,
   sourceTitle,
   onOpenSourceThread,
diff --git a/apps/web/src/threadRoutes.ts b/apps/web/src/threadRoutes.ts
index fd5bc39d836a..273588e05cbb 100644
--- a/apps/web/src/threadRoutes.ts
+++ b/apps/web/src/threadRoutes.ts
@@ -49,6 +49,16 @@ export function buildThreadRouteParams(ref: ScopedThreadRef): {
   };
 }
 
+export function buildThreadRouteLocation(ref: ScopedThreadRef): {
+  to: "/$environmentId/$threadId";
+  params: ReturnType<typeof buildThreadRouteParams>;
+} {
+  return {
+    to: "/$environmentId/$threadId",
+    params: buildThreadRouteParams(ref),
+  };
+}
+
 export function buildDraftThreadRouteParams(draftId: DraftId): {
   draftId: DraftId;
 } {
diff --git a/pnpm-lock.yaml b/pnpm-lock.yaml
index cdcca6f13e1f..6b4288325205 100644
--- a/pnpm-lock.yaml
+++ b/pnpm-lock.yaml
@@ -118,7 +118,7 @@ importers:
         version: 7.0.0-dev.20260604.1
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   apps/desktop:
     dependencies:
@@ -185,7 +185,7 @@ importers:
         version: 4.3.0
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   apps/marketing:
     dependencies:
@@ -527,7 +527,7 @@ importers:
         version: link:../../packages/effect-codex-app-server
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   apps/web:
     dependencies:
@@ -685,6 +685,9 @@ importers:
       compression:
         specifier: ^1.8.1
         version: 1.8.1
+      happy-dom:
+        specifier: ^20.12.0
+        version: 20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6)
       msw:
         specifier: 2.12.11
         version: 2.12.11(@types/node@24.12.4)(typescript@6.0.3)
@@ -696,7 +699,7 @@ importers:
         version: '@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0)'
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   infra/relay:
     dependencies:
@@ -751,7 +754,7 @@ importers:
         version: '@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0)'
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   oxlint-plugin-t3code:
     dependencies:
@@ -770,7 +773,7 @@ importers:
         version: 4.0.0-beta.103(patch_hash=a16b1e870d8c29e4a98b17cc4c638a4ff471753d8ca3487f78a22b759caf951b)(effect@4.0.0-beta.103(patch_hash=af36b7948b6f9c56623074662b51dade5699880c1a7c71245de73e13c3185fb6))
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   packages/client-runtime:
     dependencies:
@@ -789,7 +792,7 @@ importers:
         version: 4.0.0-beta.103(patch_hash=a16b1e870d8c29e4a98b17cc4c638a4ff471753d8ca3487f78a22b759caf951b)(effect@4.0.0-beta.103(patch_hash=af36b7948b6f9c56623074662b51dade5699880c1a7c71245de73e13c3185fb6))
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   packages/contracts:
     dependencies:
@@ -802,7 +805,7 @@ importers:
         version: 4.0.0-beta.103(patch_hash=a16b1e870d8c29e4a98b17cc4c638a4ff471753d8ca3487f78a22b759caf951b)(effect@4.0.0-beta.103(patch_hash=af36b7948b6f9c56623074662b51dade5699880c1a7c71245de73e13c3185fb6))
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   packages/effect-acp:
     dependencies:
@@ -824,7 +827,7 @@ importers:
         version: 24.12.4
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   packages/effect-codex-app-server:
     dependencies:
@@ -846,7 +849,7 @@ importers:
         version: 24.12.4
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   packages/shared:
     dependencies:
@@ -880,7 +883,7 @@ importers:
         version: 24.12.4
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   packages/ssh:
     dependencies:
@@ -905,7 +908,7 @@ importers:
         version: 24.12.4
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   packages/tailscale:
     dependencies:
@@ -927,7 +930,7 @@ importers:
         version: 24.12.4
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   scripts:
     dependencies:
@@ -967,7 +970,7 @@ importers:
         version: 6.0.5
       vite-plus:
         specifier: 'catalog:'
-        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+        version: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
 packages:
 
@@ -4837,6 +4840,9 @@ packages:
   '@types/webidl-conversions@7.0.3':
     resolution: {integrity: sha512-CiJJvcRtIgzadHCYXw7dqEnMNRjhGZlYK05Mj9OyktqV8uVT8fD2BFOB7S1uwBE3Kj2Z+4UyPmFw/Ixgw/LAlA==}
 
+  '@types/whatwg-mimetype@3.0.2':
+    resolution: {integrity: sha512-c2AKvDT8ToxLIOUlN51gTiHXflsfIFisS4pO7pDPoKouJCESkhZnEy623gwP9laCy5lnLDAw1vAzu2vM2YLOrA==}
+
   '@types/whatwg-url@11.0.5':
     resolution: {integrity: sha512-coYR071JRaHa+xoEvvYqvnIHaVqaYrLPbsufM9BF63HkwI5Lgmy2QR8Q5K/lYDYo5AK82wOvSOS0UsLTpTG7uQ==}
 
@@ -5576,6 +5582,10 @@ packages:
   buffer-from@1.1.2:
     resolution: {integrity: sha512-E+XQCRwSbaaiChtv6k6Dwgc+bx+Bs6vuKJHHl5kox/BaKbhiXzqQOwK4cO22yElGp2OCmjwVhT3HmxgyPGnJfQ==}
 
+  buffer-image-size@0.6.4:
+    resolution: {integrity: sha512-nEh+kZOPY1w+gcCMobZ6ETUp9WfibndnosbpwB1iJk/8Gt5ZF2bhS6+B6bPYz424KtwsR6Rflc3tCz1/ghX2dQ==}
+    engines: {node: '>=4.0'}
+
   bufferutil@4.1.0:
     resolution: {integrity: sha512-ZMANVnAixE6AWWnPzlW2KpUrxhm9woycYvPOo67jWHyFowASTEd9s+QN1EIMsSDtwhIxN4sWE1jotpuDUIgyIw==}
     engines: {node: '>=6.14.2'}
@@ -6326,6 +6336,10 @@ packages:
     resolution: {integrity: sha512-aN97NXWF6AWBTahfVOIrB/NShkzi5H7F9r1s9mD3cDj4Ko5f2qhhVoYMibXF7GlLveb/D2ioWay8lxI97Ven3g==}
     engines: {node: '>=0.12'}
 
+  entities@7.0.1:
+    resolution: {integrity: sha512-TWrgLOFUQTH994YUyl1yT4uyavY5nNB5muff+RtWaqNVCAK408b5ZnnbNAUEWLTCpum9w6arT70i1XdQ4UeOPA==}
+    engines: {node: '>=0.12'}
+
   env-paths@2.2.1:
     resolution: {integrity: sha512-+h1lkLKhZMTYjog1VEpJNG7NZJWcuc2DDk/qsqSTRRCOXiLjeQ1d1/udrUGhqMxUgAlwKNZ0cf2uqan5GLuS2A==}
     engines: {node: '>=6'}
@@ -7001,6 +7015,10 @@ packages:
   h3@1.15.11:
     resolution: {integrity: sha512-L3THSe2MPeBwgIZVSH5zLdBBU90TOxarvhK9d04IDY2AmVS8j2Jz2LIWtwsGOU3lu2I5jCN7FNvVfY2+XyF+mg==}
 
+  happy-dom@20.12.0:
+    resolution: {integrity: sha512-7uMYJu2SEwwL8vVcKp0C0lnt6d2LSGGe+T+oY79PiCJNNSgFpbxW8n5KuzpDQvrU4mt+fYiK1+Jy7Z2v39YR6g==}
+    engines: {node: '>=20.0.0'}
+
   has-flag@3.0.0:
     resolution: {integrity: sha512-sKJf1+ceQBr4SMkvQnBDNDtf4TXpVhVGateu0t918bl30FnbE2m4vNLX+VWe/dpjlb+HugGYzW7uQXH98HPEYw==}
     engines: {node: '>=4'}
@@ -10185,6 +10203,10 @@ packages:
   whatwg-fetch@3.6.20:
     resolution: {integrity: sha512-EqhiFU6daOA8kpjOWTL0olhVOF3i7OrFzSYiGsEMB8GcXS+RrzauAERX65xMeNWVqxA6HXH2m69Z9LaKKdisfg==}
 
+  whatwg-mimetype@3.0.0:
+    resolution: {integrity: sha512-nt+N2dzIutVRxARx1nghPKGv1xHikU7HKdfafKkLNLindmPU/ch3U31NOCGGA/dmPcmb1VlofO0vnKAcsm0o/Q==}
+    engines: {node: '>=12'}
+
   whatwg-url-minimum@0.1.2:
     resolution: {integrity: sha512-XPEm0XFQWNVG292lII1PrRRJl3sItrs7CettZ4ncYxuDVpLyy+NwlGyut2hXI0JswcJUxeCH+CyOJK0ZzAXD6A==}
 
@@ -14624,6 +14646,8 @@ snapshots:
 
   '@types/webidl-conversions@7.0.3': {}
 
+  '@types/whatwg-mimetype@3.0.2': {}
+
   '@types/whatwg-url@11.0.5':
     dependencies:
       '@types/webidl-conversions': 7.0.3
@@ -14702,7 +14726,7 @@ snapshots:
       '@testing-library/dom': 10.4.1
       '@testing-library/user-event': 14.6.1(@testing-library/dom@10.4.1)
       '@vitest/browser': 4.1.9(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(bufferutil@4.1.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(utf-8-validate@6.0.6)(vitest@4.1.9)
-      vitest: 4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))
+      vitest: 4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))
     transitivePeerDependencies:
       - bufferutil
       - msw
@@ -14718,7 +14742,7 @@ snapshots:
       pngjs: 7.0.0
       sirv: 3.0.2
       tinyrainbow: 3.1.0
-      vitest: 4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))
+      vitest: 4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))
       ws: 8.21.0(bufferutil@4.1.0)(utf-8-validate@6.0.6)
     transitivePeerDependencies:
       - bufferutil
@@ -15476,6 +15500,10 @@ snapshots:
 
   buffer-from@1.1.2: {}
 
+  buffer-image-size@0.6.4:
+    dependencies:
+      '@types/node': 24.12.4
+
   bufferutil@4.1.0:
     dependencies:
       node-gyp-build: 4.8.4
@@ -16129,6 +16157,8 @@ snapshots:
 
   entities@6.0.1: {}
 
+  entities@7.0.1: {}
+
   env-paths@2.2.1: {}
 
   environment@1.1.0: {}
@@ -17090,6 +17120,19 @@ snapshots:
       ufo: 1.6.4
       uncrypto: 0.1.3
 
+  happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6):
+    dependencies:
+      '@types/node': 24.12.4
+      '@types/whatwg-mimetype': 3.0.2
+      '@types/ws': 8.18.1
+      buffer-image-size: 0.6.4
+      entities: 7.0.1
+      whatwg-mimetype: 3.0.0
+      ws: 8.21.0(bufferutil@4.1.0)(utf-8-validate@6.0.6)
+    transitivePeerDependencies:
+      - bufferutil
+      - utf-8-validate
+
   has-flag@3.0.0: {}
 
   has-flag@4.0.0: {}
@@ -18876,7 +18919,7 @@ snapshots:
 
   outvariant@1.4.3: {}
 
-  oxfmt@0.57.0(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)):
+  oxfmt@0.57.0(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)):
     dependencies:
       tinypool: 2.1.0
     optionalDependencies:
@@ -18899,7 +18942,7 @@ snapshots:
       '@oxfmt/binding-win32-arm64-msvc': 0.57.0
       '@oxfmt/binding-win32-ia32-msvc': 0.57.0
       '@oxfmt/binding-win32-x64-msvc': 0.57.0
-      vite-plus: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+      vite-plus: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   oxlint-tsgolint@0.24.0:
     optionalDependencies:
@@ -18910,7 +18953,7 @@ snapshots:
       '@oxlint-tsgolint/win32-arm64': 0.24.0
       '@oxlint-tsgolint/win32-x64': 0.24.0
 
-  oxlint@1.72.0(oxlint-tsgolint@0.24.0)(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)):
+  oxlint@1.72.0(oxlint-tsgolint@0.24.0)(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)):
     optionalDependencies:
       '@oxlint/binding-android-arm-eabi': 1.72.0
       '@oxlint/binding-android-arm64': 1.72.0
@@ -18932,7 +18975,7 @@ snapshots:
       '@oxlint/binding-win32-ia32-msvc': 1.72.0
       '@oxlint/binding-win32-x64-msvc': 1.72.0
       oxlint-tsgolint: 0.24.0
-      vite-plus: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
+      vite-plus: 0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0)
 
   p-cancelable@2.1.1: {}
 
@@ -20733,7 +20776,7 @@ snapshots:
       '@types/unist': 3.0.3
       vfile-message: 4.0.3
 
-  vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0):
+  vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0):
     dependencies:
       '@oxc-project/types': 0.138.0
       '@oxlint/plugins': 1.68.0
@@ -20747,11 +20790,11 @@ snapshots:
       '@vitest/spy': 4.1.9
       '@vitest/utils': 4.1.9
       '@voidzero-dev/vite-plus-core': 0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0)
-      oxfmt: 0.57.0(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0))
-      oxlint: 1.72.0(oxlint-tsgolint@0.24.0)(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0))
+      oxfmt: 0.57.0(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0))
+      oxlint: 1.72.0(oxlint-tsgolint@0.24.0)(vite-plus@0.2.2(@types/node@24.12.4)(bufferutil@4.1.0)(esbuild@0.28.1)(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(jiti@2.7.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(utf-8-validate@6.0.6)(yaml@2.9.0))
       oxlint-tsgolint: 0.24.0
       vite: '@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0)'
-      vitest: 4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))
+      vitest: 4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))
     optionalDependencies:
       '@voidzero-dev/vite-plus-darwin-arm64': 0.2.2
       '@voidzero-dev/vite-plus-darwin-x64': 0.2.2
@@ -20795,7 +20838,7 @@ snapshots:
     optionalDependencies:
       vite: '@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0)'
 
-  vitest@4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3)):
+  vitest@4.1.9(@types/node@24.12.4)(@vitest/browser-preview@4.1.9)(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(happy-dom@20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3)):
     dependencies:
       '@vitest/expect': 4.1.9
       '@vitest/mocker': 4.1.9(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))
@@ -20820,6 +20863,7 @@ snapshots:
     optionalDependencies:
       '@types/node': 24.12.4
       '@vitest/browser-preview': 4.1.9(@voidzero-dev/vite-plus-core@0.2.2(@types/node@24.12.4)(esbuild@0.28.1)(jiti@2.7.0)(terser@5.48.0)(typescript@6.0.3)(unrun@0.2.39)(yaml@2.9.0))(bufferutil@4.1.0)(msw@2.12.11(@types/node@24.12.4)(typescript@6.0.3))(utf-8-validate@6.0.6)(vitest@4.1.9)
+      happy-dom: 20.12.0(bufferutil@4.1.0)(utf-8-validate@6.0.6)
     transitivePeerDependencies:
       - msw
 
@@ -20950,6 +20994,8 @@ snapshots:
 
   whatwg-fetch@3.6.20: {}
 
+  whatwg-mimetype@3.0.0: {}
+
   whatwg-url-minimum@0.1.2: {}
 
   whatwg-url@14.2.0:

From ba3e1b64bb5a2d8d5940d71c3addbb2ca02469df Mon Sep 17 00:00:00 2001
From: Michael Johnston <lastobelus@mac.com>
Date: Sun, 30 Aug 2026 14:46:59 -0700
Subject: [PATCH 5/5] fix(web): preserve agent message controls

---
 apps/web/src/components/chat/MessagesTimeline.test.tsx | 3 +++
 apps/web/src/components/chat/MessagesTimeline.tsx      | 9 ++++++++-
 2 files changed, 11 insertions(+), 1 deletion(-)

diff --git a/apps/web/src/components/chat/MessagesTimeline.test.tsx b/apps/web/src/components/chat/MessagesTimeline.test.tsx
index df844d83f83b..4c9a0432dcd1 100644
--- a/apps/web/src/components/chat/MessagesTimeline.test.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.test.tsx
@@ -312,6 +312,7 @@ describe("MessagesTimeline", () => {
     const markup = renderToStaticMarkup(
       <MessagesTimeline
         {...buildProps()}
+        revertTurnCountByUserMessageId={new Map([[entry.message.id, 1]])}
         timelineEntries={[
           {
             ...entry,
@@ -337,7 +338,9 @@ describe("MessagesTimeline", () => {
     expect(markup).toContain("AGENT MESSAGE");
     expect(markup).toContain("Mobile Reconnect Issue");
     expect(markup).toContain("Working");
+    expect(markup).not.toContain("animate-status-pulse");
     expect(markup).toContain('aria-label="Open source thread: Mobile Reconnect Issue"');
+    expect(markup).toContain('aria-label="Revert to this message"');
     expect(markup).toContain('download="handoff.pdf"');
   });
 
diff --git a/apps/web/src/components/chat/MessagesTimeline.tsx b/apps/web/src/components/chat/MessagesTimeline.tsx
index ae4ea9a3bd80..b04cac050606 100644
--- a/apps/web/src/components/chat/MessagesTimeline.tsx
+++ b/apps/web/src/components/chat/MessagesTimeline.tsx
@@ -1255,7 +1255,7 @@ function AgentMessageTimelineRow({
 
   const source = useThreadShell(scopeThreadRef(ctx.activeThreadEnvironmentId, sourceThreadId));
   const compactStatus = useClientSettings((settings) => settings.compactLegacySidebarStatuses);
-  const status = source
+  const resolvedStatus = source
     ? (resolveThreadStatusPill({ thread: source }) ??
       (source.session?.status === "error"
         ? {
@@ -1271,6 +1271,8 @@ function AgentMessageTimelineRow({
             pulse: false,
           }))
     : null;
+  const status = resolvedStatus ? { ...resolvedStatus, pulse: false } : null;
+  const canRevertAgentWork = typeof row.revertTurnCount === "number";
   const sourceTitle = source?.title ?? "source thread";
   const images = (row.message.attachments ?? []).filter(isImageAttachment);
   const files = (row.message.attachments ?? []).filter(isFileAttachment);
@@ -1313,6 +1315,11 @@ function AgentMessageTimelineRow({
           skills={ctx.skills}
         />
       </div>
+      {canRevertAgentWork ? (
+        <div className="flex w-full max-w-[80%] items-center justify-start ps-1 text-xs opacity-0 transition-opacity duration-200 focus-within:opacity-100 group-hover:opacity-100">
+          <RevertUserMessageButton messageId={row.message.id} />
+        </div>
+      ) : null}
     </div>
   );
 }