Open exact chats through workspace links

client/features/chat/ChatPanel.tsx

@@ -3,7 +3,7 @@ import { Link } from 'wouter'
 
 import { IconArrowBackUp, IconChevronDown, IconChevronsRight, IconX } from '@tabler/icons-react'
 import { draftSessionId } from '@/lib/session-drafts'
-import { workspaceTabPath } from '@/lib/navigation'
+import { addressPath } from '@/lib/navigation'
 import { useCurrentTabId } from './sessions/useSelectedSession'
 
 import { canSubmitComposerAction, focusComposer } from '@/client/components/shared/Composer'
@@ -205,7 +205,7 @@ export function ChatPanel({
           <div className="mx-auto flex w-full max-w-(--chat-max-container) flex-1 flex-col gap-6">
             {forkedFromSessionId && (
               <Link
-                href={workspaceTabPath(workspaceId, 'overview')}
+                href={addressPath(workspaceId, { sessionId: forkedFromSessionId, search: '' })}
                 className="block text-sm outline-none focus-visible:ring-3 focus-visible:ring-ring/50"
               >
                 <div className="flex items-center gap-3">

client/features/chat/messages/MarkdownContent.test.tsx

@@ -8,12 +8,13 @@ test('chat renders portable links as native workspace hrefs with the deployment
   const html = renderToStaticMarkup(
     <Router base="/prefix">
       <Workspace id="abc">
-        <MarkdownContent content="[Event](moi:/views/events?eventId=123) [Web](https://example.com/)" />
+        <MarkdownContent content="[Event](moi:/views/events?eventId=123) [Chat](moi:/chats/chat-1) [Web](https://example.com/)" />
       </Workspace>
     </Router>
   )
   expect(html).toContain('href="/prefix/workspace/abc/views/events?eventId=123"')
   expect(html).toContain('href="https://example.com/"')
+  expect(html).toContain('href="/prefix/workspace/abc/chats/chat-1"')
 })
 
 test('invalid moi links and executable URLs stay sanitized, including images', () => {

client/features/chat/sessions/api.ts

@@ -14,12 +14,16 @@ import type {
   WorkspaceSessionSelection
 } from '@/lib/types'
 
-export function useWorkspaceSessions(workspaceId: string) {
-  return useQuery<SessionInfo[]>({
+export function workspaceSessionsOptions(workspaceId: string) {
+  return {
     queryKey: workspaceKeys.sessions(workspaceId),
-    queryFn: () => requestJson(`/api/workspaces/${workspaceId}/sessions`),
+    queryFn: () => requestJson<SessionInfo[]>(`/api/workspaces/${workspaceId}/sessions`),
     ...WORKSPACE_RESOURCE_OPTIONS
-  })
+  }
+}
+
+export function useWorkspaceSessions(workspaceId: string) {
+  return useQuery(workspaceSessionsOptions(workspaceId))
 }
 
 export function removeArchivedSession(

client/features/chat/sessions/chat-link.ts

@@ -0,0 +1,37 @@
+import type { QueryClient } from '@tanstack/react-query'
+import { workspaceKeys } from '@/client/api/workspace-keys'
+import { workspaceSessionsOptions } from './api'
+import { tabAvailable } from '@/client/features/workspace/tab-resolution'
+import { isWorkspaceTabId } from '@/lib/workspace-tabs'
+import type { SessionInfo, ViewInfo, WorkspaceTabId } from '@/lib/types'
+
+// Metadata alone does not establish existence: the sessions API combines the
+// harness's live chat list with moi's attribution records.
+export async function resolveChatLink(
+  queryClient: QueryClient,
+  workspaceId: string,
+  sessionId: string,
+  views: ViewInfo[],
+  signal: AbortSignal
+): Promise<WorkspaceTabId | null> {
+  signal.throwIfAborted()
+  let session = queryClient
+    .getQueryData<SessionInfo[]>(workspaceKeys.sessions(workspaceId))
+    ?.find(session => session.sessionId === sessionId)
+  if (!session) {
+    const sessions = await queryClient.fetchQuery(workspaceSessionsOptions(workspaceId))
+    session = sessions.find(session => session.sessionId === sessionId)
+  }
+  signal.throwIfAborted()
+  if (!session) return null
+  const tab = isWorkspaceTabId(session.tabId) ? session.tabId : 'overview'
+  if (!tabAvailable(tab, views)) {
+    await queryClient.refetchQueries(
+      { queryKey: workspaceKeys.views(workspaceId), exact: true },
+      { throwOnError: true }
+    )
+    signal.throwIfAborted()
+    views = queryClient.getQueryData<ViewInfo[]>(workspaceKeys.views(workspaceId)) ?? views
+  }
+  return tabAvailable(tab, views) ? tab : null
+}

client/features/chat/sessions/useSelectedSession.ts

@@ -31,7 +31,8 @@ type SetSelectedSession = (sessionId: string | null) => void
 
 type SelectedSessionResult = readonly [
   sessionId: string | null | undefined,
-  setSessionId: SetSelectedSession
+  setSessionId: SetSelectedSession,
+  selectSessionForTab: (sessionId: string, tabId: WorkspaceTabId) => Promise<void>
 ]
 
 export type SelectedSessionSaveResult = 'applied' | 'conflict' | 'ignored'
@@ -41,6 +42,23 @@ export function selectedSessionKey(workspaceId: string, scope: SelectedSessionSc
   return scope === 'browser-tab' ? ([...key, 'browser-tab'] as const) : key
 }
 
+export function selectedSessionOptions(
+  workspaceId: string,
+  scope: SelectedSessionScope = 'shared'
+) {
+  return {
+    queryKey: selectedSessionKey(workspaceId, scope),
+    queryFn: () =>
+      scope === 'browser-tab'
+        ? Promise.resolve(readSelectedSession(workspaceId))
+        : requestJson<WorkspaceSessionSelection>(`/api/workspaces/${workspaceId}/selected-session`),
+    staleTime: Infinity,
+    gcTime: 0,
+    refetchOnMount: false,
+    refetchOnWindowFocus: false
+  }
+}
+
 function selectedSessionMutationKey(workspaceId: string, scope: SelectedSessionScope) {
   return [...selectedSessionKey(workspaceId, scope), 'save'] as const
 }
@@ -179,21 +197,11 @@ export function useSelectedSession(explicitTabId?: WorkspaceTabId): SelectedSess
   // WorkspaceContent remains an observer for the active workspace. Nested hook
   // users reuse its result without refetching; once the route unmounts, dropping
   // the cache makes the next visit load the server-owned selection again.
-  const query = useQuery<WorkspaceSessionSelection>({
-    queryKey,
-    queryFn: () =>
-      scope === 'browser-tab'
-        ? Promise.resolve(readSelectedSession(workspaceId))
-        : requestJson(`/api/workspaces/${workspaceId}/selected-session`),
-    staleTime: Infinity,
-    gcTime: 0,
-    refetchOnMount: false,
-    refetchOnWindowFocus: false
-  })
+  const query = useQuery(selectedSessionOptions(workspaceId, scope))
   // A pin is shared with CLI creation and applies to every workspace tab.
   const sharedSelection = useWorkspaceSessionSelection().data
 
-  const { mutate: saveSelectedSession } = useMutation<
+  const { mutate: saveSelectedSession, mutateAsync: saveSelectedSessionAsync } = useMutation<
     SelectedSessionState,
     Error,
     SaveSelectedSessionInput
@@ -253,6 +261,27 @@ export function useSelectedSession(explicitTabId?: WorkspaceTabId): SelectedSess
     [queryClient, saveSelectedSession, workspaceId, tabId, scope]
   )
 
+  const selectSessionForTab = useCallback(
+    async (sessionId: string, destination: WorkspaceTabId) => {
+      const input = optimisticallySetSelectedSession(
+        queryClient,
+        workspaceId,
+        sessionId,
+        destination,
+        scope
+      )
+      if (!input) return
+      const saved = await saveSelectedSessionAsync(input)
+      if (
+        saved.sessionId !== sessionId ||
+        queryClient.getQueryData<WorkspaceSessionSelection>(queryKey)?.selected[destination] !==
+          sessionId
+      )
+        throw new Error('Couldn’t save selected chat')
+    },
+    [queryClient, queryKey, saveSelectedSessionAsync, scope, workspaceId]
+  )
+
   useWorkspaceEvent(event => {
     if (event.type !== 'selected-session:updated' || event.workspaceId !== workspaceId) return
     applySelectedSessionEvent(queryClient, workspaceId, scope === 'shared' && pendingSaves > 0)
@@ -266,19 +295,12 @@ export function useSelectedSession(explicitTabId?: WorkspaceTabId): SelectedSess
           tabId,
           scope === 'browser-tab' ? query.data : undefined
         )
-  return [selectedSessionId, setSelectedSessionId]
+  return [selectedSessionId, setSelectedSessionId, selectSessionForTab]
 }
 
 function useWorkspaceSessionSelection() {
   const workspaceId = useWorkspaceId()
-  return useQuery<WorkspaceSessionSelection>({
-    queryKey: appUiKeys.sessionSelection(workspaceId),
-    queryFn: () => requestJson(`/api/workspaces/${workspaceId}/selected-session`),
-    staleTime: Infinity,
-    gcTime: 0,
-    refetchOnMount: false,
-    refetchOnWindowFocus: false
-  })
+  return useQuery(selectedSessionOptions(workspaceId))
 }
 
 export function usePinnedSession() {
@@ -322,6 +344,7 @@ export function usePinnedSession() {
   return {
     pinnedSessionId: data?.pinned ?? null,
     loaded: data !== undefined,
-    pin: mutation.mutate
+    pin: mutation.mutate,
+    pinAsync: mutation.mutateAsync
   }
 }

client/features/workspace/WorkspaceScreen.tsx

@@ -157,6 +157,10 @@
   // Split needs enough row width; the saved mode remains the user's intent.
   const wantsSplit = layout.layoutMode === 'split'
   const mode: LayoutMode = wantsSplit && canUseSplit ? 'split' : 'fullscreen'
+  const revealLinkedChat = useCallback(() => {
+    setFloatingChatOpen(true)
+    setChatFocusRequest(request => request + 1)
+  }, [])
 
   // The tab address: URL in, active tab + applet params out, plus the persisted
   // tab state it keeps in sync. See useWorkspaceNavigation for the invariants.
@@ -169,7 +173,8 @@
     isUnavailable,
     onNavigationClick
   } = useWorkspaceNavigation({
-    views: allViews
+    views: allViews,
+    onOpenChat: revealLinkedChat
   })
 
   // Chat comes after navigation, and takes the address: every message carries
@@ -264,13 +269,13 @@
 
   useEffect(() => {
     if (mode !== 'fullscreen') {
       setFloatingChatOpen(false)
     }
   }, [mode])
 
   useEffect(() => {
     if (!activeDraftViewId) return
     if (mode === 'fullscreen') setFloatingChatOpen(true)
     setChatFocusRequest(request => request + 1)
   }, [activeDraftViewId, mode])