feat(web): identify cross-thread agent messages

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,

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();

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()) }

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,

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",

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,