fix: stabilize scoped AI draft/session transitions (#724)

* fix: correct terminal AI history resume behavior

The previous implementation plan mistakenly treated reopening an old terminal AI session in a fresh or reconnected SSH tab as a scope-retargeting feature.

The intended rule is draft-first:
- a fresh or reconnected terminal opens on a blank draft
- older chats remain available in history for manual access
- selecting history does not imply automatic scope transfer into the new tab

This change is a rule correction, not a conflict between product rules.

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>

* fix: harden ai draft transitions

* fix ai session continuation from history

* fix: clear stale activeSessionIdMap entry when view resolves to draft

Addresses the Codex P2 review on aiPanelViewState.ts:38. When a terminal
scope mounts with a persisted activeSessionIdMap entry but no explicit
panelView and no draft, resolveDisplayedPanelView now returns the
default draft view (terminal fresh-start behavior). The sync effect
that writes into activeSessionIdMap is guarded by `if (!activeSession)
return`, so the old entry stays put. That stale entry then leaks into
activeTerminalTargetIds in every other scope, and
getSessionScopeMatchRank uses it to suppress host-matched history that
is actually resumable — so valid sessions vanish from the history
drawer until another action rewrites the map.

Add a dedicated effect that clears the scope's activeSessionIdMap
entry whenever the resolved panel view is draft but a persisted
session id is still present. This keeps the map an accurate record of
"which session each scope is currently showing" instead of a lagging
snapshot.

Also extend sessionScopeMatch.test.ts to cover the rank=2 exact-match
branch and the scope-type mismatch short-circuit, which were missing
from the original suite.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

* fix: track cross-terminal session ownership by session id, not targetId

Addresses the Codex follow-up review on commit 345244b2. When a user
resumes a session from history into a different terminal, the session's
`scope.targetId` still points at the original terminal. The previous
ownership tracking — which checked whether `session.scope.targetId`
appeared in `activeTerminalTargetIds` (derived from the keys of
`activeSessionIdMap`) — therefore:

- could not prevent the same session from being resumed in multiple
  terminals simultaneously, because the resumed session's targetId
  never matches the current scope's targetId; and
- let `pruneInactiveScopedSessions` treat a session as orphaned and
  clear its `externalSessionId` the moment the original terminal
  closed, even though another terminal was actively using it.

Switch ownership to be keyed on session id:

- `getSessionScopeMatchRank` now takes `activeTerminalSessionIds`
  (a Set of session ids currently displayed by other terminal scopes)
  and returns rank 0 when `session.id` is in that set.
- `AIChatSidePanel` derives `activeTerminalSessionIds` from the
  *values* of `activeSessionIdMap`, excluding the current scope's key.
- `pruneInactiveScopedSessions` gains an `activeSessionIds` parameter;
  sessions whose id is in this set are never reported as orphaned and
  never have their `externalSessionId` cleared, regardless of their
  stored `scope.targetId`.
- `cleanupOrphanedAISessions` computes the in-use set from the
  pre-cleanup `activeSessionIdMap`, filtered to live scopes, and
  passes it through. The map is read once and reused.

Tests cover the new id-based ownership, the rank-2 exact-match path,
the scope-type-mismatch short-circuit, and the
"resumed-elsewhere session must not be cleaned" invariant.

Co-Authored-By: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

---------

Co-authored-by: Copilot <223556219+Copilot@users.noreply.github.com>
Co-authored-by: bincxz <16399091+binaricat@users.noreply.github.com>
Co-authored-by: Claude Opus 4.6 (1M context) <noreply@anthropic.com>

application/state/aiDraftState.test.ts

@@ -3,9 +3,13 @@ import assert from "node:assert/strict";
 
 import {
   activateDraftView,
+  bumpDraftMutationVersionState,
+  bumpDraftUploadGenerationState,
   clearScopeDraftState,
   createEmptyDraft,
   ensureDraftForScopeState,
+  getDraftMutationVersionState,
+  getDraftUploadGenerationState,
   pruneTerminalScopeState,
   pruneTerminalTransientState,
   resolvePanelView,
@@ -168,6 +172,28 @@ test("ensureDraftForScopeState returns the original ref when the scope already e
   assert.equal(next, draftsByScope);
 });
 
+test("draft mutation version increments on every mutation for the same scope", () => {
+  const scopeKey = "terminal:1";
+  const initialVersion = getDraftMutationVersionState({}, scopeKey);
+  const nextVersions = bumpDraftMutationVersionState({}, scopeKey);
+  const finalVersions = bumpDraftMutationVersionState(nextVersions, scopeKey);
+
+  assert.equal(initialVersion, 0);
+  assert.equal(getDraftMutationVersionState(nextVersions, scopeKey), 1);
+  assert.equal(getDraftMutationVersionState(finalVersions, scopeKey), 2);
+});
+
+test("draft upload generation only increments when the draft lifecycle rolls over", () => {
+  const scopeKey = "terminal:1";
+  const initialGeneration = getDraftUploadGenerationState({}, scopeKey);
+  const nextGenerations = bumpDraftUploadGenerationState({}, scopeKey);
+  const finalGenerations = bumpDraftUploadGenerationState(nextGenerations, scopeKey);
+
+  assert.equal(initialGeneration, 0);
+  assert.equal(getDraftUploadGenerationState(nextGenerations, scopeKey), 1);
+  assert.equal(getDraftUploadGenerationState(finalGenerations, scopeKey), 2);
+});
+
 test("pruneTerminalScopeState removes closed terminal drafts and views only", () => {
   const draftsByScope = {
     "terminal:closed": createEmptyDraft("agent-alpha"),

application/state/aiDraftState.ts

@@ -6,6 +6,8 @@ import type {
 type DraftsByScope = Partial<Record<string, AIDraft>>;
 type PanelViewByScope = Partial<Record<string, AIPanelView>>;
 type ActiveSessionIdMap = Record<string, string | null>;
+type DraftMutationVersionByScope = Record<string, number>;
+type DraftUploadGenerationByScope = Record<string, number>;
 
 const DEFAULT_PANEL_VIEW: AIPanelView = { mode: 'draft' };
 
@@ -19,6 +21,40 @@ export function createEmptyDraft(agentId: string): AIDraft {
   };
 }
 
+export function getDraftMutationVersionState(
+  versionsByScope: DraftMutationVersionByScope,
+  scopeKey: string,
+): number {
+  return versionsByScope[scopeKey] ?? 0;
+}
+
+export function bumpDraftMutationVersionState(
+  versionsByScope: DraftMutationVersionByScope,
+  scopeKey: string,
+): DraftMutationVersionByScope {
+  return {
+    ...versionsByScope,
+    [scopeKey]: getDraftMutationVersionState(versionsByScope, scopeKey) + 1,
+  };
+}
+
+export function getDraftUploadGenerationState(
+  generationsByScope: DraftUploadGenerationByScope,
+  scopeKey: string,
+): number {
+  return generationsByScope[scopeKey] ?? 0;
+}
+
+export function bumpDraftUploadGenerationState(
+  generationsByScope: DraftUploadGenerationByScope,
+  scopeKey: string,
+): DraftUploadGenerationByScope {
+  return {
+    ...generationsByScope,
+    [scopeKey]: getDraftUploadGenerationState(generationsByScope, scopeKey) + 1,
+  };
+}
+
 export function resolvePanelView(
   panelViewByScope: PanelViewByScope,
   scopeKey: string,

application/state/aiScopeCleanup.test.ts

@@ -129,3 +129,35 @@ test("pruneInactiveScopedSessions preserves original sessions when orphaned rest
   assert.deepEqual(next.orphanedSessionIds, ["terminal-restorable"]);
   assert.equal(next.sessions, sessions);
 });
+
+test("pruneInactiveScopedSessions treats sessions displayed elsewhere as in-use, not orphaned", () => {
+  // terminal-restorable's original scope (terminal-closed-A) is gone, but
+  // the user resumed it into terminal-open-B from history. The session's
+  // externalSessionId must be preserved and it must not appear in the
+  // orphaned list, otherwise the active chat loses ACP continuity.
+  const resumedElsewhere = createSession("terminal-restorable", {
+    type: "terminal",
+    targetId: "terminal-closed-A",
+    hostIds: ["host-1"],
+  }, "ext-resumed");
+
+  const trulyOrphaned = createSession("terminal-stale", {
+    type: "terminal",
+    targetId: "terminal-closed-C",
+    hostIds: ["host-2"],
+  }, "ext-stale");
+
+  const sessions = [resumedElsewhere, trulyOrphaned];
+
+  const next = pruneInactiveScopedSessions(
+    sessions,
+    new Set(["terminal-open-B"]),
+    new Set(["terminal-restorable"]),
+  );
+
+  // Only the one not being displayed anywhere should show up as orphaned.
+  assert.deepEqual(next.orphanedSessionIds, ["terminal-stale"]);
+  // The resumed session must retain its externalSessionId.
+  const resumedNext = next.sessions.find((s) => s.id === "terminal-restorable");
+  assert.equal(resumedNext?.externalSessionId, "ext-resumed");
+});

application/state/aiScopeCleanup.ts

@@ -99,12 +99,21 @@ function isRestorableTerminalSession(session: AISession): boolean {
 export function pruneInactiveScopedSessions(
   sessions: AISession[],
   activeTargetIds: Set<string>,
+  /**
+   * Session ids currently displayed by any live scope. A session whose
+   * `scope.targetId` is inactive but whose id is still in use somewhere
+   * (e.g. resumed from history into a different terminal) must not be
+   * treated as orphaned — clearing its `externalSessionId` or deleting
+   * it outright would break the chat the user is actively continuing.
+   */
+  activeSessionIds: Set<string> = new Set(),
 ): {
   sessions: AISession[];
   orphanedSessionIds: string[];
 } {
   const orphanedSessionIds = sessions
     .filter((session) => session.scope.targetId && !activeTargetIds.has(session.scope.targetId))
+    .filter((session) => !activeSessionIds.has(session.id))
     .map((session) => session.id);
 
   if (orphanedSessionIds.length === 0) {

application/state/useAIState.ts

@@ -33,8 +33,11 @@ import type {
 import { DEFAULT_COMMAND_BLOCKLIST } from '../../infrastructure/ai/types';
 import {
   activateDraftView,
+  bumpDraftMutationVersionState,
+  bumpDraftUploadGenerationState,
   clearScopeDraftState,
   ensureDraftForScopeState,
+  getDraftUploadGenerationState,
   setSessionView,
   updateDraftForScope,
 } from './aiDraftState';
@@ -91,9 +94,26 @@ export function cleanupOrphanedAISessions(activeTargetIds: Set<string>) {
   const currentSessions = latestAISessionsSnapshot
     ?? localStorageAdapter.read<AISession[]>(STORAGE_KEY_AI_SESSIONS)
     ?? [];
+
+  // Sessions shown by a still-live scope must be protected from cleanup
+  // even when their own `scope.targetId` points at a closed terminal —
+  // history can be resumed into a different terminal and we must not
+  // clear its `externalSessionId` (or delete it outright) while it's
+  // actively being used.
+  const preCleanupActiveSessionMap = latestAIActiveSessionMapSnapshot
+    ?? localStorageAdapter.read<Record<string, string | null>>(STORAGE_KEY_AI_ACTIVE_SESSION_MAP)
+    ?? {};
+  const activeSessionIds = new Set<string>();
+  for (const [scopeKey, sessionId] of Object.entries(preCleanupActiveSessionMap)) {
+    if (!sessionId) continue;
+    if (!isScopeKeyActive(scopeKey, activeTargetIds)) continue;
+    activeSessionIds.add(sessionId);
+  }
+
   const nextSessionCleanup = pruneInactiveScopedSessions(
     currentSessions,
     activeTargetIds,
+    activeSessionIds,
   );
 
   if (nextSessionCleanup.orphanedSessionIds.length > 0) {
@@ -109,9 +129,7 @@ export function cleanupOrphanedAISessions(activeTargetIds: Set<string>) {
     emitAIStateChanged(STORAGE_KEY_AI_SESSIONS);
   }
 
-  const activeSessionIdMap = latestAIActiveSessionMapSnapshot
-    ?? localStorageAdapter.read<Record<string, string | null>>(STORAGE_KEY_AI_ACTIVE_SESSION_MAP)
-    ?? {};
+  const activeSessionIdMap = preCleanupActiveSessionMap;
   let activeSessionMapChanged = false;
   const nextActiveSessionIdMap = { ...activeSessionIdMap };
 
@@ -152,6 +170,7 @@ export function cleanupOrphanedAISessions(activeTargetIds: Set<string>) {
     for (const scopeKey of Object.keys(currentDraftsByScope)) {
       if (scopeKey in prunedScopedTransientState.draftsByScope) continue;
       bumpDraftMutationVersion(scopeKey);
+      bumpDraftUploadGeneration(scopeKey);
     }
     setLatestAIDraftsByScopeSnapshot(prunedScopedTransientState.draftsByScope);
     emitAIStateChanged(AI_STATE_CHANGED_DRAFTS_BY_SCOPE);
@@ -198,6 +217,7 @@ let latestAIActiveSessionMapSnapshot: Record<string, string | null> | null = nul
 let latestAIDraftsByScopeSnapshot: DraftsByScope | null = null;
 let latestAIPanelViewByScopeSnapshot: PanelViewByScope | null = null;
 let latestAIDraftMutationVersionByScopeSnapshot: Record<string, number> = {};
+let latestAIDraftUploadGenerationByScopeSnapshot: Record<string, number> = {};
 
 function setLatestAISessionsSnapshot(sessions: AISession[]) {
   latestAISessionsSnapshot = sessions;
@@ -207,19 +227,6 @@ function setLatestAIActiveSessionMapSnapshot(activeSessionIdMap: Record<string,
   latestAIActiveSessionMapSnapshot = activeSessionIdMap;
 }
 
-function buildScopeKey(scope: AISessionScope) {
-  return `${scope.type}:${scope.targetId ?? ''}`;
-}
-
-function areHostIdsEqual(left?: string[], right?: string[]) {
-  const leftIds = left ?? [];
-  const rightIds = right ?? [];
-  if (leftIds.length !== rightIds.length) return false;
-
-  const rightSet = new Set(rightIds);
-  return leftIds.every((hostId) => rightSet.has(hostId));
-}
-
 function setLatestAIDraftsByScopeSnapshot(draftsByScope: DraftsByScope) {
   latestAIDraftsByScopeSnapshot = draftsByScope;
 }
@@ -228,15 +235,25 @@ function setLatestAIPanelViewByScopeSnapshot(panelViewByScope: PanelViewByScope)
   latestAIPanelViewByScopeSnapshot = panelViewByScope;
 }
 
-function getDraftMutationVersion(scopeKey: string) {
-  return latestAIDraftMutationVersionByScopeSnapshot[scopeKey] ?? 0;
+function bumpDraftMutationVersion(scopeKey: string) {
+  latestAIDraftMutationVersionByScopeSnapshot = bumpDraftMutationVersionState(
+    latestAIDraftMutationVersionByScopeSnapshot,
+    scopeKey,
+  );
 }
 
-function bumpDraftMutationVersion(scopeKey: string) {
-  latestAIDraftMutationVersionByScopeSnapshot = {
-    ...latestAIDraftMutationVersionByScopeSnapshot,
-    [scopeKey]: getDraftMutationVersion(scopeKey) + 1,
-  };
+function getDraftUploadGeneration(scopeKey: string) {
+  return getDraftUploadGenerationState(
+    latestAIDraftUploadGenerationByScopeSnapshot,
+    scopeKey,
+  );
+}
+
+function bumpDraftUploadGeneration(scopeKey: string) {
+  latestAIDraftUploadGenerationByScopeSnapshot = bumpDraftUploadGenerationState(
+    latestAIDraftUploadGenerationByScopeSnapshot,
+    scopeKey,
+  );
 }
 
 export function useAIState() {
@@ -788,60 +805,6 @@ export function useAIState() {
     });
   }, [debouncedPersistSessions]);
 
-  const retargetSessionScope = useCallback((sessionId: string, scope: AISessionScope) => {
-    const currentSession = sessionsRef.current.find((session) => session.id === sessionId);
-    if (!currentSession) return;
-
-    const currentScope = currentSession.scope;
-    const scopeChanged =
-      currentScope.type !== scope.type
-      || currentScope.targetId !== scope.targetId
-      || !areHostIdsEqual(currentScope.hostIds, scope.hostIds);
-
-    const nextScopeKey = buildScopeKey(scope);
-    const currentScopeKey = buildScopeKey(currentScope);
-
-    if (scopeChanged) {
-      setSessionsRaw((prev) => {
-        let changed = false;
-        const next = prev.map((session) => {
-          if (session.id !== sessionId) return session;
-          changed = true;
-          return { ...session, scope, externalSessionId: undefined };
-        });
-
-        if (!changed) return prev;
-
-        sessionsRef.current = next;
-        setLatestAISessionsSnapshot(next);
-        persistSessions(next);
-        return next;
-      });
-    }
-
-    setActiveSessionIdMapRaw((prev) => {
-      let changed = false;
-      const next = { ...prev };
-
-      if (currentScopeKey !== nextScopeKey && next[currentScopeKey] === sessionId) {
-        delete next[currentScopeKey];
-        changed = true;
-      }
-
-      if (next[nextScopeKey] !== sessionId) {
-        next[nextScopeKey] = sessionId;
-        changed = true;
-      }
-
-      if (!changed) return prev;
-
-      setLatestAIActiveSessionMapSnapshot(next);
-      localStorageAdapter.write(STORAGE_KEY_AI_ACTIVE_SESSION_MAP, next);
-      emitAIStateChanged(STORAGE_KEY_AI_ACTIVE_SESSION_MAP);
-      return next;
-    });
-  }, [persistSessions]);
-
   // Maximum messages per session to prevent unbounded memory growth
   const MAX_MESSAGES_PER_SESSION = 500;
 
@@ -947,12 +910,15 @@ export function useAIState() {
       emitAIStateChanged(AI_STATE_CHANGED_DRAFTS_BY_SCOPE);
       return next;
     });
+    bumpDraftMutationVersion(scopeKey);
   }, []);
 
   const updateDraftIfPresent = useCallback((
     scopeKey: string,
     updater: (draft: AIDraft) => AIDraft,
   ): void => {
+    let updated = false;
+
     setDraftsByScopeRaw((prev) => {
       const currentDraft = prev[scopeKey];
       if (!currentDraft) return prev;
@@ -965,10 +931,15 @@ export function useAIState() {
         ...prev,
         [scopeKey]: nextDraft,
       };
+      updated = true;
       setLatestAIDraftsByScopeSnapshot(next);
       emitAIStateChanged(AI_STATE_CHANGED_DRAFTS_BY_SCOPE);
       return next;
     });
+
+    if (updated) {
+      bumpDraftMutationVersion(scopeKey);
+    }
   }, []);
 
   const showDraftView = useCallback((scopeKey: string) => {
@@ -1031,6 +1002,7 @@ export function useAIState() {
     if (!draftsChanged && !panelViewChanged) return;
 
     bumpDraftMutationVersion(scopeKey);
+    bumpDraftUploadGeneration(scopeKey);
 
     if (draftsChanged && nextDraftsByScope) {
       setLatestAIDraftsByScopeSnapshot(nextDraftsByScope);
@@ -1050,11 +1022,11 @@ export function useAIState() {
     inputFiles: File[],
   ) => {
     ensureDraftForScope(scopeKey, fallbackAgentId);
-    const initialMutationVersion = getDraftMutationVersion(scopeKey);
+    const initialUploadGeneration = getDraftUploadGeneration(scopeKey);
     const uploads = await convertFilesToUploads(inputFiles);
     if (uploads.length === 0) return;
 
-    if (getDraftMutationVersion(scopeKey) !== initialMutationVersion) {
+    if (getDraftUploadGeneration(scopeKey) !== initialUploadGeneration) {
       return;
     }
 
@@ -1175,7 +1147,6 @@ export function useAIState() {
     deleteSessionsByTarget,
     updateSessionTitle,
     updateSessionExternalSessionId,
-    retargetSessionScope,
     addMessageToSession,
     updateLastMessage,
     updateMessageById,

components/AIChatSidePanel.tsx

@@ -47,11 +47,17 @@ import {
   type UserSkillOption,
 } from './ai/userSkillsState';
 import {
+  applyDraftEntrySelection,
   applyHistorySessionSelection,
   resolveDisplayedPanelView,
   resolveDisplayedSession,
-  shouldRetargetSessionForScope,
 } from './ai/aiPanelViewState';
+import {
+  endDraftSend,
+  tryBeginDraftSend,
+} from './ai/draftSendGate';
+import { getSessionScopeMatchRank } from './ai/sessionScopeMatch';
+import { SESSION_HISTORY_ROW_CLASSNAMES } from './ai/sessionHistoryLayout';
 import type { CodexIntegrationStatus } from './settings/tabs/ai/types';
 import {
   useAIChatStreaming,
@@ -102,7 +108,6 @@ interface AIChatSidePanelProps {
   deleteSession: (sessionId: string, scopeKey?: string) => void;
   updateSessionTitle: (sessionId: string, title: string) => void;
   updateSessionExternalSessionId: (sessionId: string, externalSessionId: string | undefined) => void;
-  retargetSessionScope: (sessionId: string, scope: AISessionScope) => void;
   addMessageToSession: (sessionId: string, message: ChatMessage) => void;
   updateLastMessage: (
     sessionId: string,
@@ -201,27 +206,6 @@ function buildAcpHistoryMessages(messages: ChatMessage[]): Array<{ role: 'user'
   });
 }
 
-function getSessionScopeMatchRank(
-  session: AISession,
-  scopeType: 'terminal' | 'workspace',
-  scopeTargetId?: string,
-  scopeHostIds?: string[],
-  activeTerminalTargetIds?: Set<string>,
-): number {
-  if (session.scope.type !== scopeType) return 0;
-  if (session.scope.targetId === scopeTargetId) return 2;
-
-  if (scopeType !== 'terminal' || !scopeHostIds?.length || !session.scope.hostIds?.length) {
-    return 0;
-  }
-
-  if (session.scope.targetId && activeTerminalTargetIds?.has(session.scope.targetId)) {
-    return 0;
-  }
-
-  return session.scope.hostIds.some((hostId) => scopeHostIds.includes(hostId)) ? 1 : 0;
-}
-
 // -------------------------------------------------------------------
 // Component
 // -------------------------------------------------------------------
@@ -243,7 +227,6 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
   deleteSession,
   updateSessionTitle,
   updateSessionExternalSessionId,
-  retargetSessionScope,
   addMessageToSession,
   updateLastMessage,
   updateMessageById,
@@ -302,36 +285,42 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
     setActiveSessionIdForScope(scopeKey, id);
   }, [scopeKey, setActiveSessionIdForScope]);
 
-  const activeTerminalTargetIds = useMemo(() => {
-    const targetIds = new Set<string>();
-    for (const [sessionScopeKey, sessionId] of Object.entries(activeSessionIdMap)) {
+  const activeTerminalSessionIds = useMemo(() => {
+    const sessionIds = new Set<string>();
+    const entries = Object.entries(activeSessionIdMap) as Array<[string, string | null]>;
+    for (const [sessionScopeKey, sessionId] of entries) {
       if (!sessionScopeKey.startsWith('terminal:') || !sessionId) continue;
-      const targetId = sessionScopeKey.slice('terminal:'.length);
-      if (!targetId || targetId === scopeTargetId) continue;
-      targetIds.add(targetId);
+      if (sessionScopeKey === scopeKey) continue;
+      sessionIds.add(sessionId);
     }
-    return targetIds;
-  }, [activeSessionIdMap, scopeTargetId]);
+    return sessionIds;
+  }, [activeSessionIdMap, scopeKey]);
 
   const historySessions = useMemo(
     () =>
       sessions
         .map((session) => ({
           session,
-          matchRank: getSessionScopeMatchRank(session, scopeType, scopeTargetId, scopeHostIds, activeTerminalTargetIds),
+          matchRank: getSessionScopeMatchRank(
+            session,
+            scopeType,
+            scopeTargetId,
+            scopeHostIds,
+            activeTerminalSessionIds,
+          ),
         }))
         .filter(({ matchRank }) => matchRank > 0)
         .sort((a, b) => b.matchRank - a.matchRank || b.session.updatedAt - a.session.updatedAt)
         .map(({ session }) => session),
-    [sessions, scopeType, scopeTargetId, scopeHostIds, activeTerminalTargetIds],
+    [sessions, scopeType, scopeTargetId, scopeHostIds, activeTerminalSessionIds],
   );
 
   const explicitPanelView = panelViewByScope[scopeKey];
   const currentDraft = draftsByScope[scopeKey] ?? null;
   const persistedSessionId = activeSessionIdMap[scopeKey] ?? null;
   const normalizedPanelView = useMemo<AIPanelView>(
-    () => resolveDisplayedPanelView(explicitPanelView, currentDraft != null, historySessions, persistedSessionId),
-    [explicitPanelView, currentDraft, historySessions, persistedSessionId],
+    () => resolveDisplayedPanelView(explicitPanelView, currentDraft != null, historySessions, persistedSessionId, scopeType),
+    [explicitPanelView, currentDraft, historySessions, persistedSessionId, scopeType],
   );
   const activeSession = useMemo(
     () => resolveDisplayedSession(normalizedPanelView, historySessions),
@@ -348,6 +337,7 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
   currentDraftRef.current = currentDraft;
   const activeSessionRef = useRef(activeSession);
   activeSessionRef.current = activeSession;
+  const draftSendInFlightRef = useRef(false);
 
   const defaultTargetSession = useMemo<DefaultTargetSessionHint | undefined>(() => {
     const connectedSessions = terminalSessions.filter((session) => session.connected !== false);
@@ -385,40 +375,9 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
     showDraftView(scopeKey);
   }, [normalizedPanelView, explicitPanelView, scopeKey, showDraftView]);
 
-  const shouldRetargetActiveSession = useMemo(() => {
-    return shouldRetargetSessionForScope(
-      activeSession,
-      scopeType,
-      scopeTargetId,
-      scopeHostIds,
-      activeTerminalTargetIds,
-    );
-  }, [activeSession, scopeType, scopeTargetId, scopeHostIds, activeTerminalTargetIds]);
-
   useEffect(() => {
     if (!activeSession) return;
 
-    if (shouldRetargetActiveSession && isVisible) {
-      if (streamingSessionIds.has(activeSession.id)) {
-        const controller = abortControllersRef.current.get(activeSession.id);
-        if (controller) {
-          controller.abort();
-          abortControllersRef.current.delete(activeSession.id);
-        }
-        setStreamingForScope(activeSession.id, false);
-        clearAllPendingApprovals(activeSession.id);
-        const bridge = getNetcattyBridge();
-        bridge?.aiCattyCancelExec?.(activeSession.id);
-        bridge?.aiAcpCancel?.('', activeSession.id);
-      }
-      retargetSessionScope(activeSession.id, {
-        type: scopeType,
-        targetId: scopeTargetId,
-        hostIds: scopeHostIds,
-      });
-      return;
-    }
-
     if (isVisible && activeSessionIdMap[scopeKey] !== activeSession.id) {
       setActiveSessionId(activeSession.id);
     }
@@ -426,18 +385,22 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
     activeSession,
     activeSessionIdMap,
     scopeKey,
-    retargetSessionScope,
     isVisible,
-    scopeHostIds,
-    scopeTargetId,
-    scopeType,
     setActiveSessionId,
-    setStreamingForScope,
-    shouldRetargetActiveSession,
-    streamingSessionIds,
-    abortControllersRef,
   ]);
 
+  // When the resolved view is draft but activeSessionIdMap still points at a
+  // previously-shown session, clear that stale entry. Otherwise
+  // activeTerminalTargetIds keeps claiming ownership of the old session's
+  // target and getSessionScopeMatchRank suppresses matching history from
+  // other terminals until another action rewrites the map.
+  useEffect(() => {
+    if (!isVisible) return;
+    if (normalizedPanelView.mode !== 'draft') return;
+    if (persistedSessionId == null) return;
+    setActiveSessionId(null);
+  }, [isVisible, normalizedPanelView.mode, persistedSessionId, setActiveSessionId]);
+
   const ensureScopeDraft = useCallback((agentId: string) => {
     ensureDraftForScope(scopeKey, agentId);
   }, [ensureDraftForScope, scopeKey]);
@@ -461,16 +424,26 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
     clearDraftForScope(scopeKey);
   }, [clearDraftForScope, scopeKey]);
 
+  const enterScopeDraftMode = useCallback((agentId: string, preserveSessionView = false) => {
+    applyDraftEntrySelection({
+      ensureDraft: () => ensureScopeDraft(agentId),
+      showDraftView: showScopeDraftView,
+      preserveSessionView,
+    });
+  }, [ensureScopeDraft, showScopeDraftView]);
+
   const setInputValue = useCallback((value: string) => {
+    enterScopeDraftMode(currentAgentId, panelViewRef.current.mode === 'session');
     updateScopeDraft(currentAgentId, (draft) => ({
       ...draft,
       text: value,
     }));
-  }, [currentAgentId, updateScopeDraft]);
+  }, [currentAgentId, enterScopeDraftMode, updateScopeDraft]);
 
   const addFiles = useCallback(async (inputFiles: File[]) => {
+    enterScopeDraftMode(currentAgentId, panelViewRef.current.mode === 'session');
     await addDraftFiles(scopeKey, currentAgentId, inputFiles);
-  }, [addDraftFiles, scopeKey, currentAgentId]);
+  }, [addDraftFiles, currentAgentId, enterScopeDraftMode, scopeKey]);
 
   const removeFile = useCallback((fileId: string) => {
     removeDraftFile(scopeKey, currentAgentId, fileId);
@@ -810,6 +783,7 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
   const addSelectedUserSkill = useCallback((slug: string) => {
     const normalizedSlug = String(slug || '').trim().toLowerCase();
     if (!normalizedSlug) return;
+    enterScopeDraftMode(currentAgentId, panelViewRef.current.mode === 'session');
     updateScopeDraft(currentAgentId, (draft) => {
       if (draft.selectedUserSkillSlugs.includes(normalizedSlug)) {
         return draft;
@@ -819,11 +793,12 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
         selectedUserSkillSlugs: [...draft.selectedUserSkillSlugs, normalizedSlug],
       };
     });
-  }, [currentAgentId, updateScopeDraft]);
+  }, [currentAgentId, enterScopeDraftMode, updateScopeDraft]);
 
   const removeSelectedUserSkill = useCallback((slug: string) => {
     const normalizedSlug = String(slug || '').trim().toLowerCase();
     if (!normalizedSlug) return;
+    enterScopeDraftMode(currentAgentId, panelViewRef.current.mode === 'session');
     updateScopeDraft(currentAgentId, (draft) => {
       const nextSelectedUserSkillSlugs = draft.selectedUserSkillSlugs.filter(
         (entry) => entry !== normalizedSlug,
@@ -836,7 +811,7 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
         selectedUserSkillSlugs: nextSelectedUserSkillSlugs,
       };
     });
-  }, [currentAgentId, updateScopeDraft]);
+  }, [currentAgentId, enterScopeDraftMode, updateScopeDraft]);
 
   // -------------------------------------------------------------------
   // Main send handler (thin orchestrator)
@@ -859,110 +834,120 @@ const AIChatSidePanelInner: React.FC<AIChatSidePanelProps> = ({
       filename: file.filename,
       filePath: file.filePath,
     }));
+    const isDraftMode = currentPanelView.mode === 'draft';
 
-    let sessionId = currentSessionView?.id ?? null;
-    let currentSession = currentSessionView ?? null;
-    let sendAgentId = currentSessionView?.agentId ?? draft?.agentId ?? currentAgentId;
-
-    if (currentPanelView.mode === 'draft') {
-      const scope: AISessionScope = { type: scopeType, targetId: scopeTargetId, hostIds: scopeHostIds };
-      const createdSession = createSession(scope, sendAgentId);
-      sessionId = createdSession.id;
-      currentSession = createdSession;
-      clearScopeDraft();
-      showScopeSessionView(createdSession.id);
-      setActiveSessionId(createdSession.id);
-    }
-
-    if (!sessionId) {
+    if (isDraftMode && !tryBeginDraftSend(draftSendInFlightRef)) {
       return;
     }
 
-    const isExternalAgent = sendAgentId !== 'catty';
+    try {
+      let sessionId = currentSessionView?.id ?? null;
+      let currentSession = currentSessionView ?? null;
+      const sendAgentId = currentSessionView?.agentId ?? draft?.agentId ?? currentAgentId;
 
-    // No provider configured for built-in agent
-    if (!isExternalAgent && !activeProvider) {
-      addMessageToSession(sessionId, { id: generateId(), role: 'user', content: trimmed, timestamp: Date.now() });
-      addMessageToSession(sessionId, { id: generateId(), role: 'assistant', content: t('ai.chat.noProvider'), timestamp: Date.now() });
-      if (currentPanelView.mode === 'session') {
+      if (isDraftMode) {
+        const scope: AISessionScope = { type: scopeType, targetId: scopeTargetId, hostIds: scopeHostIds };
+        const createdSession = createSession(scope, sendAgentId);
+        sessionId = createdSession.id;
+        currentSession = createdSession;
         clearScopeDraft();
-        showScopeSessionView(sessionId);
+        showScopeSessionView(createdSession.id);
+        setActiveSessionId(createdSession.id);
       }
-      return;
-    }
 
-    // Add user message
-    addMessageToSession(sessionId, {
-      id: generateId(), role: 'user', content: trimmed,
-      ...(attachments.length > 0 ? { attachments } : {}),
-      timestamp: Date.now(),
-    });
-    clearScopeDraft();
-    showScopeSessionView(sessionId);
-    setActiveSessionId(sessionId);
-    setStreamingForScope(sessionId, true);
-
-    // Create assistant message placeholder with a tracked ID
-    const agentConfig = isExternalAgent ? externalAgents.find((agent) => agent.id === sendAgentId) : undefined;
-    const assistantMsgId = generateId();
-    addMessageToSession(sessionId, {
-      id: assistantMsgId, role: 'assistant', content: '', timestamp: Date.now(),
-      model: isExternalAgent
-        ? (selectedAgentModel || agentConfig?.name || 'external')
-        : (activeModelId || activeProvider?.defaultModel || ''),
-      providerId: isExternalAgent ? undefined : activeProvider?.providerId,
-    });
-
-    const abortController = new AbortController();
-    abortControllersRef.current.set(sessionId, abortController);
-    currentSession = currentSession ?? sessionsRef.current.find((session) => session.id === sessionId) ?? null;
-
-    if (isExternalAgent) {
-      if (!agentConfig) {
-        updateMessageById(sessionId, assistantMsgId, msg => ({ ...msg, content: 'External agent not found. Please check settings.', executionStatus: 'failed' }));
-        setStreamingForScope(sessionId, false);
+      if (!sessionId) {
         return;
       }
-      try {
-        await sendToExternalAgent(sessionId, trimmed, agentConfig, abortController, attachments, {
-          existingSessionId: currentSession?.externalSessionId,
-          updateExternalSessionId: updateSessionExternalSessionId,
-          historyMessages: buildAcpHistoryMessages(currentSession?.messages ?? []),
-          terminalSessions,
-          defaultTargetSession,
-          providers,
-          selectedAgentModel,
-          toolIntegrationMode,
-          selectedUserSkillSlugs: selectedSkillSlugs,
-        });
-      } catch (err) {
-        reportStreamError(sessionId, abortController.signal, err);
+
+      const isExternalAgent = sendAgentId !== 'catty';
+
+      // No provider configured for built-in agent
+      if (!isExternalAgent && !activeProvider) {
+        addMessageToSession(sessionId, { id: generateId(), role: 'user', content: trimmed, timestamp: Date.now() });
+        addMessageToSession(sessionId, { id: generateId(), role: 'assistant', content: t('ai.chat.noProvider'), timestamp: Date.now() });
+        if (currentPanelView.mode === 'session') {
+          clearScopeDraft();
+          showScopeSessionView(sessionId);
+        }
+        return;
+      }
+
+      // Add user message
+      addMessageToSession(sessionId, {
+        id: generateId(), role: 'user', content: trimmed,
+        ...(attachments.length > 0 ? { attachments } : {}),
+        timestamp: Date.now(),
+      });
+      clearScopeDraft();
+      showScopeSessionView(sessionId);
+      setActiveSessionId(sessionId);
+      setStreamingForScope(sessionId, true);
+
+      // Create assistant message placeholder with a tracked ID
+      const agentConfig = isExternalAgent ? externalAgents.find((agent) => agent.id === sendAgentId) : undefined;
+      const assistantMsgId = generateId();
+      addMessageToSession(sessionId, {
+        id: assistantMsgId, role: 'assistant', content: '', timestamp: Date.now(),
+        model: isExternalAgent
+          ? (selectedAgentModel || agentConfig?.name || 'external')
+          : (activeModelId || activeProvider?.defaultModel || ''),
+        providerId: isExternalAgent ? undefined : activeProvider?.providerId,
+      });
+
+      const abortController = new AbortController();
+      abortControllersRef.current.set(sessionId, abortController);
+      currentSession = currentSession ?? sessionsRef.current.find((session) => session.id === sessionId) ?? null;
+
+      if (isExternalAgent) {
+        if (!agentConfig) {
+          updateMessageById(sessionId, assistantMsgId, msg => ({ ...msg, content: 'External agent not found. Please check settings.', executionStatus: 'failed' }));
+          setStreamingForScope(sessionId, false);
+          return;
+        }
+        try {
+          await sendToExternalAgent(sessionId, trimmed, agentConfig, abortController, attachments, {
+            existingSessionId: currentSession?.externalSessionId,
+            updateExternalSessionId: updateSessionExternalSessionId,
+            historyMessages: buildAcpHistoryMessages(currentSession?.messages ?? []),
+            terminalSessions,
+            defaultTargetSession,
+            providers,
+            selectedAgentModel,
+            toolIntegrationMode,
+            selectedUserSkillSlugs: selectedSkillSlugs,
+          });
+        } catch (err) {
+          reportStreamError(sessionId, abortController.signal, err);
+        }
+        updateLastMessage(sessionId, msg => msg.statusText ? { ...msg, statusText: '' } : msg);
+        setStreamingForScope(sessionId, false);
+        abortControllersRef.current.delete(sessionId);
+        autoTitleSession(sessionId, trimmed);
+      } else {
+        const toolScope = {
+          type: scopeType,
+          targetId: scopeTargetId,
+          label: scopeLabel,
+        } as const;
+        await sendToCattyAgent(sessionId, sendScopeKey, trimmed, abortController, currentSession ?? undefined, assistantMsgId, {
+          activeProvider,
+          activeModelId,
+          scopeType,
+          scopeTargetId,
+          scopeLabel,
+          globalPermissionMode,
+          commandBlocklist,
+          terminalSessions,
+          webSearchConfig,
+          getExecutorContext: () => buildExecutorContextForScope(toolScope),
+          autoTitleSession,
+          selectedUserSkillSlugs: selectedSkillSlugs,
+        }, attachments.length > 0 ? attachments : undefined);
+      }
+    } finally {
+      if (isDraftMode) {
+        endDraftSend(draftSendInFlightRef);
       }
-      // Clear any lingering statusText when the external agent stream finishes
-      updateLastMessage(sessionId, msg => msg.statusText ? { ...msg, statusText: '' } : msg);
-      setStreamingForScope(sessionId, false);
-      abortControllersRef.current.delete(sessionId);
-      autoTitleSession(sessionId, trimmed);
-    } else {
-      const toolScope = {
-        type: scopeType,
-        targetId: scopeTargetId,
-        label: scopeLabel,
-      } as const;
-      await sendToCattyAgent(sessionId, sendScopeKey, trimmed, abortController, currentSession ?? undefined, assistantMsgId, {
-        activeProvider,
-        activeModelId,
-        scopeType,
-        scopeTargetId,
-        scopeLabel,
-        globalPermissionMode,
-        commandBlocklist,
-        terminalSessions,
-        webSearchConfig,
-        getExecutorContext: () => buildExecutorContextForScope(toolScope),
-        autoTitleSession,
-        selectedUserSkillSlugs: selectedSkillSlugs,
-      }, attachments.length > 0 ? attachments : undefined);
     }
   }, [
     isStreaming, activeProvider, scopeKey, currentAgentId,
@@ -1203,20 +1188,20 @@ const SessionHistoryDrawer: React.FC<SessionHistoryDrawerProps> = ({
                   onClick={() => onSelect(session.id)}
                   onKeyDown={(e) => { if (e.key === 'Enter' || e.key === ' ') onSelect(session.id); }}
                   className={cn(
-                    'w-full flex items-center justify-between py-2.5 border-b border-border/20 text-left transition-colors cursor-pointer group',
+                    SESSION_HISTORY_ROW_CLASSNAMES.row,
                     isActive ? 'text-foreground' : 'text-foreground/70 hover:text-foreground',
                   )}
                 >
-                  <span className="text-[13px] truncate pr-3 flex-1 min-w-0">
+                  <span className={SESSION_HISTORY_ROW_CLASSNAMES.title}>
                     {session.title || t('ai.chat.untitled')}
                   </span>
-                  <div className="flex items-center gap-2 shrink-0">
-                    <span className="text-[12px] text-muted-foreground/50">
+                  <div className={SESSION_HISTORY_ROW_CLASSNAMES.meta}>
+                    <span className={SESSION_HISTORY_ROW_CLASSNAMES.time}>
                       {timeStr}
                     </span>
                     <button
                       onClick={(e) => onDelete(e, session.id)}
-                      className="opacity-0 group-hover:opacity-100 p-0.5 hover:text-destructive transition-all cursor-pointer"
+                      className={SESSION_HISTORY_ROW_CLASSNAMES.deleteButton}
                       title="Delete"
                     >
                       <Trash2 size={12} />

components/TerminalLayer.tsx

@@ -340,7 +340,6 @@ const AIChatPanelsHostInner: React.FC<AIChatPanelsHostProps> = ({
               deleteSession={aiState.deleteSession}
               updateSessionTitle={aiState.updateSessionTitle}
               updateSessionExternalSessionId={aiState.updateSessionExternalSessionId}
-              retargetSessionScope={aiState.retargetSessionScope}
               addMessageToSession={aiState.addMessageToSession}
               updateLastMessage={aiState.updateLastMessage}
               updateMessageById={aiState.updateMessageById}

components/ai/ChatInput.tsx

@@ -7,7 +7,7 @@
  */
 
 import { AtSign, Check, ChevronDown, ChevronRight, Cpu, Expand, Eye, FileText, ImageIcon, Package, Plus, ShieldCheck, X, Zap } from 'lucide-react';
-import React, { useCallback, useRef, useState } from 'react';
+import React, { useCallback, useEffect, useMemo, useRef, useState } from 'react';
 import { useI18n } from '../../application/i18n/I18nProvider';
 import { createPortal } from 'react-dom';
 import type { FormEvent } from 'react';
@@ -100,6 +100,8 @@ const ChatInput: React.FC<ChatInputProps> = ({
   const [hoveredModelId, setHoveredModelId] = useState<string | null>(null);
   const [slashQuery, setSlashQuery] = useState('');
   const [slashRange, setSlashRange] = useState<{ start: number; end: number } | null>(null);
+  // Active highlight index for @ mention / slash skill keyboard navigation
+  const [activeMenuIndex, setActiveMenuIndex] = useState(0);
 
   // Derived booleans for readability
   const showModelPicker = activeMenu === 'model';
@@ -203,11 +205,11 @@ const ChatInput: React.FC<ChatInputProps> = ({
     setActiveMenu(menu);
   }, [getInputPanelMenuPos]);
 
-  const filteredUserSkills = userSkills.filter((skill) => {
+  const filteredUserSkills = useMemo(() => userSkills.filter((skill) => {
     if (!slashQuery) return true;
     const lowerQuery = slashQuery.toLowerCase();
     return skill.slug.toLowerCase().startsWith(lowerQuery) || skill.name.toLowerCase().includes(lowerQuery);
-  });
+  }), [userSkills, slashQuery]);
 
   const removeSlashQueryFromInput = useCallback(() => {
     if (!slashRange) return value;
@@ -227,6 +229,78 @@ const ChatInput: React.FC<ChatInputProps> = ({
     closeAllMenus();
   }, [closeAllMenus, onAddUserSkill, onChange, removeSlashQueryFromInput, slashRange]);
 
+  // Reset active highlight when a menu opens or when the *identity* of the
+  // visible items changes. Watching only `.length` misses cases where the
+  // filter produces a different set with the same count (e.g. user types
+  // another character into the slash query) — Enter would then commit an
+  // unexpected item. Derive a stable key from the visible ids instead.
+  const atMentionKey = useMemo(
+    () => hosts.map((h) => h.sessionId).join('|'),
+    [hosts],
+  );
+  const slashSkillKey = useMemo(
+    () => filteredUserSkills.map((s) => s.id).join('|'),
+    [filteredUserSkills],
+  );
+  useEffect(() => {
+    if (showAtMention) setActiveMenuIndex(0);
+  }, [showAtMention, atMentionKey]);
+  useEffect(() => {
+    if (showSlashSkillPicker) setActiveMenuIndex(0);
+  }, [showSlashSkillPicker, slashSkillKey]);
+
+  const handleTextareaKeyDown = useCallback((e: React.KeyboardEvent<HTMLTextAreaElement>) => {
+    if (e.nativeEvent.isComposing) return;
+    // @ mention popover keyboard navigation
+    if (showAtMention && hosts.length > 0) {
+      if (e.key === 'ArrowDown') {
+        e.preventDefault();
+        setActiveMenuIndex((i) => (i + 1) % hosts.length);
+        return;
+      }
+      if (e.key === 'ArrowUp') {
+        e.preventDefault();
+        setActiveMenuIndex((i) => (i - 1 + hosts.length) % hosts.length);
+        return;
+      }
+      if (e.key === 'Enter' && !e.shiftKey) {
+        e.preventDefault();
+        const host = hosts[Math.min(activeMenuIndex, hosts.length - 1)];
+        if (host) handleSelectAtMention(host);
+        return;
+      }
+      if (e.key === 'Escape') {
+        e.preventDefault();
+        closeAllMenus();
+        return;
+      }
+    }
+    // / skill popover keyboard navigation
+    if (showSlashSkillPicker && filteredUserSkills.length > 0) {
+      if (e.key === 'ArrowDown') {
+        e.preventDefault();
+        setActiveMenuIndex((i) => (i + 1) % filteredUserSkills.length);
+        return;
+      }
+      if (e.key === 'ArrowUp') {
+        e.preventDefault();
+        setActiveMenuIndex((i) => (i - 1 + filteredUserSkills.length) % filteredUserSkills.length);
+        return;
+      }
+      if (e.key === 'Enter' && !e.shiftKey) {
+        e.preventDefault();
+        const skill = filteredUserSkills[Math.min(activeMenuIndex, filteredUserSkills.length - 1)];
+        if (skill) insertUserSkillToken(skill);
+        return;
+      }
+      if (e.key === 'Escape') {
+        e.preventDefault();
+        closeAllMenus();
+        return;
+      }
+    }
+  }, [showAtMention, hosts, showSlashSkillPicker, filteredUserSkills, activeMenuIndex, handleSelectAtMention, insertUserSkillToken, closeAllMenus]);
+
   const handlePaste = useCallback((e: React.ClipboardEvent) => {
     const pastedFiles = Array.from(e.clipboardData.items)
       .map((item: DataTransferItem) => item.getAsFile())
@@ -367,6 +441,7 @@ const ChatInput: React.FC<ChatInputProps> = ({
             ref={textareaRef}
             value={value}
             onChange={(e) => handleInputChange(e.target.value)}
+            onKeyDown={handleTextareaKeyDown}
             placeholder={placeholder || defaultPlaceholder}
             disabled={disabled}
             className={[
@@ -392,31 +467,40 @@ const ChatInput: React.FC<ChatInputProps> = ({
             <div
               role="listbox"
               aria-label="Mention host"
-              className="fixed z-[1000] overflow-hidden rounded-[20px] border border-border/60 bg-popover shadow-2xl"
-              style={{ left: inputPanelPos.left, bottom: inputPanelPos.bottom, width: inputPanelPos.width }}
+              aria-activedescendant={hosts[activeMenuIndex] ? `at-mention-${hosts[activeMenuIndex].sessionId}` : undefined}
+              className="fixed z-[1000] overflow-hidden rounded-lg border border-border/50 bg-popover shadow-lg"
+              style={{ left: inputPanelPos.left, bottom: inputPanelPos.bottom, width: 'auto', minWidth: Math.min(200, inputPanelPos.width), maxWidth: inputPanelPos.width }}
             >
-              <div className="px-4 pt-3 pb-1.5 text-[10px] font-medium text-muted-foreground/62 tracking-wide">{t('ai.chat.menuHosts')}</div>
-              <ScrollArea className="max-h-[300px]">
-                <div className="px-2.5 pb-2.5">
-                  {hosts.map(host => (
-                    <button
-                      key={host.sessionId}
-                      type="button"
-                      role="option"
-                      onClick={() => handleSelectAtMention(host)}
-                      className="w-full rounded-[16px] px-3 py-1.5 text-left hover:bg-muted/30 transition-colors cursor-pointer"
-                    >
-                      <div className="flex items-center gap-2 text-[12px] text-foreground/90">
-                        <span className={`h-1.5 w-1.5 rounded-full shrink-0 ${host.connected ? 'bg-green-500' : 'bg-muted-foreground/30'}`} />
-                        <span className="truncate">{host.label || host.hostname}</span>
-                      </div>
-                      {host.label && host.hostname !== host.label ? (
-                        <div className="mt-0.5 pl-3.5 text-[10px] text-muted-foreground/60 truncate">
-                          {host.hostname}
+              <ScrollArea className="max-h-[280px]">
+                <div className="p-1">
+                  {hosts.map((host, idx) => {
+                    const isActive = idx === activeMenuIndex;
+                    const showHostnameLine = host.label
+                      && host.hostname !== host.label
+                      && !host.label.includes(host.hostname);
+                    return (
+                      <button
+                        id={`at-mention-${host.sessionId}`}
+                        key={host.sessionId}
+                        type="button"
+                        role="option"
+                        aria-selected={isActive}
+                        onMouseEnter={() => setActiveMenuIndex(idx)}
+                        onClick={() => handleSelectAtMention(host)}
+                        className={`w-full rounded-md px-2 py-1 text-left transition-colors cursor-pointer ${isActive ? 'bg-muted/40' : 'hover:bg-muted/30'}`}
+                      >
+                        <div className="flex items-center gap-2 text-[12px] text-foreground/90">
+                          <span className={`h-1.5 w-1.5 rounded-full shrink-0 ${host.connected ? 'bg-green-500' : 'bg-muted-foreground/30'}`} />
+                          <span className="truncate">{host.label || host.hostname}</span>
                         </div>
-                      ) : null}
-                    </button>
-                  ))}
+                        {showHostnameLine ? (
+                          <div className="pl-3.5 text-[10px] text-muted-foreground/60 truncate">
+                            {host.hostname}
+                          </div>
+                        ) : null}
+                      </button>
+                    );
+                  })}
                 </div>
               </ScrollArea>
             </div>
@@ -431,31 +515,37 @@ const ChatInput: React.FC<ChatInputProps> = ({
             <div
               role="listbox"
               aria-label="Insert user skill"
-              className="fixed z-[1000] overflow-hidden rounded-[20px] border border-border/60 bg-popover shadow-2xl"
-              style={{ left: inputPanelPos.left, bottom: inputPanelPos.bottom, width: inputPanelPos.width }}
+              aria-activedescendant={filteredUserSkills[activeMenuIndex] ? `slash-skill-${filteredUserSkills[activeMenuIndex].id}` : undefined}
+              className="fixed z-[1000] overflow-hidden rounded-lg border border-border/50 bg-popover shadow-lg"
+              style={{ left: inputPanelPos.left, bottom: inputPanelPos.bottom, width: 'auto', minWidth: Math.min(200, inputPanelPos.width), maxWidth: inputPanelPos.width }}
             >
-              <div className="px-4 pt-3 pb-1.5 text-[10px] font-medium text-muted-foreground/62 tracking-wide">{t('ai.chat.menuUserSkills')}</div>
-              <ScrollArea className="max-h-[300px]">
-                <div className="px-2.5 pb-2.5">
-                  {filteredUserSkills.map((skill) => (
-                    <button
-                      key={skill.id}
-                      type="button"
-                      role="option"
-                      onClick={() => insertUserSkillToken(skill)}
-                      className="w-full rounded-[16px] px-3 py-1.5 text-left hover:bg-muted/30 transition-colors cursor-pointer"
-                    >
-                      <div className="flex items-center gap-2 text-[12px]">
-                        <Package size={12} className="text-muted-foreground/55 shrink-0" />
-                        <span className="text-foreground/90">/{skill.slug}</span>
-                      </div>
-                      {skill.description ? (
-                        <div className="mt-0.5 pl-5 text-[10px] leading-4.5 text-muted-foreground/62 line-clamp-2">
-                          {skill.description}
+              <ScrollArea className="max-h-[280px]">
+                <div className="p-1">
+                  {filteredUserSkills.map((skill, idx) => {
+                    const isActive = idx === activeMenuIndex;
+                    return (
+                      <button
+                        id={`slash-skill-${skill.id}`}
+                        key={skill.id}
+                        type="button"
+                        role="option"
+                        aria-selected={isActive}
+                        onMouseEnter={() => setActiveMenuIndex(idx)}
+                        onClick={() => insertUserSkillToken(skill)}
+                        className={`w-full rounded-md px-2 py-1 text-left transition-colors cursor-pointer ${isActive ? 'bg-muted/40' : 'hover:bg-muted/30'}`}
+                      >
+                        <div className="flex items-center gap-2 text-[12px]">
+                          <Package size={12} className="text-muted-foreground/55 shrink-0" />
+                          <span className="text-foreground/90">/{skill.slug}</span>
                         </div>
-                      ) : null}
-                    </button>
-                  ))}
+                        {skill.description ? (
+                          <div className="pl-5 text-[10px] leading-4.5 text-muted-foreground/62 line-clamp-2">
+                            {skill.description}
+                          </div>
+                        ) : null}
+                      </button>
+                    );
+                  })}
                 </div>
               </ScrollArea>
             </div>

components/ai/aiPanelViewState.test.ts

@@ -6,11 +6,11 @@ import type {
   AISession,
 } from "../../infrastructure/ai/types.ts";
 import {
+  applyDraftEntrySelection,
   applyHistorySessionSelection,
   normalizePanelView,
   resolveDisplayedPanelView,
   resolveDisplayedSession,
-  shouldRetargetSessionForScope,
 } from "./aiPanelViewState.ts";
 
 function createSession(id: string): AISession {
@@ -61,7 +61,7 @@ test("missing explicit panel view resumes the most recent matching history when
   const sessions = [createSession("session-2"), createSession("session-1")];
 
   assert.deepEqual(
-    resolveDisplayedPanelView(undefined, false, sessions),
+    resolveDisplayedPanelView(undefined, false, sessions, undefined, "workspace"),
     { mode: "session", sessionId: "session-2" },
   );
 });
@@ -70,7 +70,7 @@ test("missing explicit panel view restores the persisted active session instead
   const sessions = [createSession("session-2"), createSession("session-1")];
 
   assert.deepEqual(
-    resolveDisplayedPanelView(undefined, false, sessions, "session-1"),
+    resolveDisplayedPanelView(undefined, false, sessions, "session-1", "workspace"),
     { mode: "session", sessionId: "session-1" },
   );
 });
@@ -79,7 +79,7 @@ test("persisted session id that no longer exists in history falls back to newest
   const sessions = [createSession("session-2"), createSession("session-1")];
 
   assert.deepEqual(
-    resolveDisplayedPanelView(undefined, false, sessions, "deleted-session"),
+    resolveDisplayedPanelView(undefined, false, sessions, "deleted-session", "workspace"),
     { mode: "session", sessionId: "session-2" },
   );
 });
@@ -88,11 +88,20 @@ test("null persisted session id falls back to newest history entry", () => {
   const sessions = [createSession("session-2"), createSession("session-1")];
 
   assert.deepEqual(
-    resolveDisplayedPanelView(undefined, false, sessions, null),
+    resolveDisplayedPanelView(undefined, false, sessions, null, "workspace"),
     { mode: "session", sessionId: "session-2" },
   );
 });
 
+test("terminal scope without explicit view always starts from draft even when history exists", () => {
+  const sessions = [createSession("session-2"), createSession("session-1")];
+
+  assert.deepEqual(
+    resolveDisplayedPanelView(undefined, false, sessions, "session-1", "terminal"),
+    { mode: "draft" },
+  );
+});
+
 test("missing explicit panel view prefers the draft when unsent input exists", () => {
   const sessions = [createSession("session-2"), createSession("session-1")];
 
@@ -109,50 +118,6 @@ test("draft state is used when there is no implicit history to resume", () => {
   );
 });
 
-test("restorable terminal history should retarget to the current scope", () => {
-  const session: AISession = {
-    ...createSession("session-2"),
-    scope: {
-      type: "terminal",
-      targetId: "old-terminal",
-      hostIds: ["host-1"],
-    },
-  };
-
-  assert.equal(
-    shouldRetargetSessionForScope(
-      session,
-      "terminal",
-      "new-terminal",
-      ["host-1"],
-      new Set<string>(),
-    ),
-    true,
-  );
-});
-
-test("session owned by another active terminal should not retarget", () => {
-  const session: AISession = {
-    ...createSession("session-2"),
-    scope: {
-      type: "terminal",
-      targetId: "other-active-terminal",
-      hostIds: ["host-1"],
-    },
-  };
-
-  assert.equal(
-    shouldRetargetSessionForScope(
-      session,
-      "terminal",
-      "new-terminal",
-      ["host-1"],
-      new Set<string>(["other-active-terminal"]),
-    ),
-    false,
-  );
-});
-
 test("history selection switches to the chosen session without touching draft state", () => {
   const calls: string[] = [];
 
@@ -174,3 +139,39 @@ test("history selection switches to the chosen session without touching draft st
     "close-history",
   ]);
 });
+
+test("draft entry ensures a draft exists before switching the panel to draft mode", () => {
+  const calls: string[] = [];
+
+  applyDraftEntrySelection({
+    ensureDraft: () => {
+      calls.push("ensure-draft");
+    },
+    showDraftView: () => {
+      calls.push("show-draft");
+    },
+  });
+
+  assert.deepEqual(calls, [
+    "ensure-draft",
+    "show-draft",
+  ]);
+});
+
+test("draft entry can preserve the current session view while ensuring draft state", () => {
+  const calls: string[] = [];
+
+  applyDraftEntrySelection({
+    ensureDraft: () => {
+      calls.push("ensure-draft");
+    },
+    showDraftView: () => {
+      calls.push("show-draft");
+    },
+    preserveSessionView: true,
+  });
+
+  assert.deepEqual(calls, [
+    "ensure-draft",
+  ]);
+});

components/ai/aiPanelViewState.ts

@@ -11,11 +11,18 @@ interface HistorySessionSelectionActions {
   closeHistory?: () => void;
 }
 
+interface DraftEntrySelectionActions {
+  ensureDraft: () => void;
+  showDraftView: () => void;
+  preserveSessionView?: boolean;
+}
+
 export function resolveDisplayedPanelView(
   panelView: AIPanelView | undefined,
   hasDraft: boolean,
   sessions: AISession[],
   persistedSessionId?: string | null,
+  scopeType: "terminal" | "workspace" = "workspace",
 ): AIPanelView {
   if (panelView) {
     return normalizePanelView(panelView, sessions);
@@ -25,6 +32,12 @@ export function resolveDisplayedPanelView(
     return DEFAULT_PANEL_VIEW;
   }
 
+  // New terminal sessions should always start from a blank draft. History is
+  // still available in the drawer, but never auto-resumed into a fresh SSH tab.
+  if (scopeType === "terminal") {
+    return DEFAULT_PANEL_VIEW;
+  }
+
   // Honour the persisted active-session selection (survives cold mount)
   // before falling back to the newest history entry.
   if (persistedSessionId && sessions.some((s) => s.id === persistedSessionId)) {
@@ -62,28 +75,6 @@ export function resolveDisplayedSession(
   return sessions.find((session) => session.id === panelView.sessionId) ?? null;
 }
 
-export function shouldRetargetSessionForScope(
-  session: AISession | null,
-  scopeType: "terminal" | "workspace",
-  scopeTargetId?: string,
-  scopeHostIds?: string[],
-  activeTerminalTargetIds?: Set<string>,
-): boolean {
-  if (!session || scopeType !== "terminal" || !scopeTargetId || !scopeHostIds?.length) {
-    return false;
-  }
-
-  if (session.scope.type !== scopeType || session.scope.targetId === scopeTargetId) {
-    return false;
-  }
-
-  if (session.scope.targetId && activeTerminalTargetIds?.has(session.scope.targetId)) {
-    return false;
-  }
-
-  return session.scope.hostIds?.some((hostId) => scopeHostIds.includes(hostId)) ?? false;
-}
-
 export function applyHistorySessionSelection(
   sessionId: string,
   actions: HistorySessionSelectionActions,
@@ -92,3 +83,12 @@ export function applyHistorySessionSelection(
   actions.setActiveSessionId(sessionId);
   actions.closeHistory?.();
 }
+
+export function applyDraftEntrySelection(
+  actions: DraftEntrySelectionActions,
+): void {
+  actions.ensureDraft();
+  if (!actions.preserveSessionView) {
+    actions.showDraftView();
+  }
+}

components/ai/draftSendGate.test.ts

@@ -0,0 +1,18 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import {
+  endDraftSend,
+  tryBeginDraftSend,
+} from "./draftSendGate.ts";
+
+test("draft send gate allows only one in-flight draft send at a time", () => {
+  const gate = { current: false };
+
+  assert.equal(tryBeginDraftSend(gate), true);
+  assert.equal(tryBeginDraftSend(gate), false);
+
+  endDraftSend(gate);
+
+  assert.equal(tryBeginDraftSend(gate), true);
+});

components/ai/draftSendGate.ts

@@ -0,0 +1,12 @@
+export function tryBeginDraftSend(gate: { current: boolean }): boolean {
+  if (gate.current) {
+    return false;
+  }
+
+  gate.current = true;
+  return true;
+}
+
+export function endDraftSend(gate: { current: boolean }): void {
+  gate.current = false;
+}

components/ai/sessionHistoryLayout.test.ts

@@ -0,0 +1,15 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import {
+  SESSION_HISTORY_ROW_CLASSNAMES,
+} from "./sessionHistoryLayout.ts";
+
+test("session history row keeps metadata pinned to the end while title truncates", () => {
+  assert.match(SESSION_HISTORY_ROW_CLASSNAMES.row, /\bgrid\b/);
+  assert.ok(SESSION_HISTORY_ROW_CLASSNAMES.row.includes('grid-cols-[minmax(0,1fr)_auto]'));
+  assert.match(SESSION_HISTORY_ROW_CLASSNAMES.title, /\btruncate\b/);
+  assert.match(SESSION_HISTORY_ROW_CLASSNAMES.title, /\bmin-w-0\b/);
+  assert.match(SESSION_HISTORY_ROW_CLASSNAMES.meta, /\bjustify-self-end\b/);
+  assert.match(SESSION_HISTORY_ROW_CLASSNAMES.meta, /\bshrink-0\b/);
+});

components/ai/sessionHistoryLayout.ts

@@ -0,0 +1,7 @@
+export const SESSION_HISTORY_ROW_CLASSNAMES = {
+  row: 'w-full grid grid-cols-[minmax(0,1fr)_auto] items-center gap-3 py-2.5 border-b border-border/20 text-left transition-colors cursor-pointer group',
+  title: 'text-[13px] truncate min-w-0',
+  meta: 'flex items-center gap-2 justify-self-end shrink-0',
+  time: 'text-[12px] text-muted-foreground/50 whitespace-nowrap',
+  deleteButton: 'opacity-0 group-hover:opacity-100 p-0.5 hover:text-destructive transition-all cursor-pointer shrink-0',
+} as const;

components/ai/sessionScopeMatch.test.ts

@@ -0,0 +1,101 @@
+import assert from "node:assert/strict";
+import test from "node:test";
+
+import type { AISession } from "../../infrastructure/ai/types.ts";
+import { getSessionScopeMatchRank } from "./sessionScopeMatch.ts";
+
+function createSession(id: string, targetId: string, hostIds: string[]): AISession {
+  return {
+    id,
+    title: id,
+    messages: [],
+    createdAt: 1,
+    updatedAt: 1,
+    agentId: "catty",
+    scope: {
+      type: "terminal",
+      targetId,
+      hostIds,
+    },
+  };
+}
+
+test("host-matched terminal session is excluded when another active terminal already displays it", () => {
+  const session = createSession("session-1", "terminal-other", ["host-a"]);
+
+  assert.equal(
+    getSessionScopeMatchRank(
+      session,
+      "terminal",
+      "terminal-current",
+      ["host-a"],
+      new Set(["session-1"]),
+    ),
+    0,
+  );
+});
+
+test("host-matched terminal session remains resumable when no terminal is displaying it", () => {
+  const session = createSession("session-1", "terminal-closed", ["host-a"]);
+
+  assert.equal(
+    getSessionScopeMatchRank(
+      session,
+      "terminal",
+      "terminal-current",
+      ["host-a"],
+      new Set(["session-other"]),
+    ),
+    1,
+  );
+});
+
+test("ownership is tracked by session id, not scope.targetId", () => {
+  // Session was created in terminal-A but a different terminal (B) is now
+  // displaying it after the user resumed it from history. Opening a third
+  // terminal (C) should not see this session as owned, because the new
+  // ownership check is keyed on session id, not the stale targetId.
+  const session = createSession("session-1", "terminal-A", ["host-a"]);
+
+  assert.equal(
+    getSessionScopeMatchRank(
+      session,
+      "terminal",
+      "terminal-C",
+      ["host-a"],
+      // terminal-B is displaying session-1; pass session-1 as an
+      // active-id so C sees it as in-use
+      new Set(["session-1"]),
+    ),
+    0,
+  );
+});
+
+test("session targeting the current scope is an exact match (rank 2)", () => {
+  const session = createSession("session-1", "terminal-current", ["host-a"]);
+
+  assert.equal(
+    getSessionScopeMatchRank(
+      session,
+      "terminal",
+      "terminal-current",
+      ["host-a"],
+      new Set(),
+    ),
+    2,
+  );
+});
+
+test("scope type mismatch returns 0 regardless of target or hosts", () => {
+  const session = createSession("session-1", "terminal-current", ["host-a"]);
+
+  assert.equal(
+    getSessionScopeMatchRank(
+      session,
+      "workspace",
+      "terminal-current",
+      ["host-a"],
+    ),
+    0,
+  );
+});

components/ai/sessionScopeMatch.ts

@@ -0,0 +1,28 @@
+import type { AISession } from "../../infrastructure/ai/types";
+
+export function getSessionScopeMatchRank(
+  session: AISession,
+  scopeType: "terminal" | "workspace",
+  scopeTargetId?: string,
+  scopeHostIds?: string[],
+  /**
+   * Session ids currently displayed by other terminal scopes. Tracked by
+   * session id rather than `scope.targetId` so that a host-matched session
+   * resumed from a different terminal is still recognised as in-use and
+   * not offered (or cleaned) as if it were orphaned.
+   */
+  activeTerminalSessionIds?: Set<string>,
+): number {
+  if (session.scope.type !== scopeType) return 0;
+  if (session.scope.targetId === scopeTargetId) return 2;
+
+  if (scopeType !== "terminal" || !scopeHostIds?.length || !session.scope.hostIds?.length) {
+    return 0;
+  }
+
+  if (activeTerminalSessionIds?.has(session.id)) {
+    return 0;
+  }
+
+  return session.scope.hostIds.some((hostId) => scopeHostIds.includes(hostId)) ? 1 : 0;
+}

electron/bridges/ai/ptyExec.cjs

@@ -88,7 +88,7 @@ function buildWrappedCommand(command, shellKind, marker) {
         `set ${marker} 0; function __ncmcp_int --on-signal INT; printf '%s\\n' '${marker}_E:130'; functions -e __ncmcp_int; end; ` +
         `set -l ${marker}_cmd '${escapeFishSingleQuoted(command)}'; ` +
         `begin; set -gx PAGER cat; set -gx SYSTEMD_PAGER ''; set -gx GIT_PAGER cat; set -gx LESS ''; ` +
-        `printf '%s\\n' '${marker}_S'; eval -- \$${marker}_cmd; set __NCMCP_rc $status; ` +
+        `printf '%s\\n' '${marker}_S'; eval \$${marker}_cmd; set __NCMCP_rc $status; ` +
         `functions -e __ncmcp_int; printf '%s\\n' '${marker}_E:'\$__NCMCP_rc; end\n`
       );