Keep explicitly reopened archived agent tabs open

packages/app/src/stores/workspace-layout-store.test.ts

@@ -218,7 +218,11 @@ describe("workspace-layout-store tree transforms", () => {
 
 describe("workspace-layout-store actions", () => {
   beforeEach(() => {
-    useWorkspaceLayoutStore.setState({ layoutByWorkspace: {} });
+    useWorkspaceLayoutStore.setState({
+      layoutByWorkspace: {},
+      splitSizesByWorkspace: {},
+      pinnedAgentIdsByWorkspace: {},
+    });
     vi.restoreAllMocks();
   });
 
@@ -634,4 +638,40 @@ describe("workspace-layout-store actions", () => {
 
     expect(layout).toEqual(createDefaultLayout());
   });
+
+  it("keeps pinned archived agents in memory per workspace without persisting them", () => {
+    const workspaceKey = createWorkspaceKey();
+    const otherWorkspaceKey = buildWorkspaceTabPersistenceKey({
+      serverId: SERVER_ID,
+      workspaceId: "/repo/other-worktree",
+    });
+
+    expect(otherWorkspaceKey).toBeTruthy();
+
+    const store = useWorkspaceLayoutStore.getState();
+    store.pinAgent(workspaceKey, "agent-1");
+    store.pinAgent(workspaceKey, "agent-1");
+    store.pinAgent(otherWorkspaceKey as string, "agent-2");
+
+    let state = useWorkspaceLayoutStore.getState();
+    expect(Array.from(state.pinnedAgentIdsByWorkspace[workspaceKey] ?? [])).toEqual(["agent-1"]);
+    expect(Array.from(state.pinnedAgentIdsByWorkspace[otherWorkspaceKey as string] ?? [])).toEqual([
+      "agent-2",
+    ]);
+
+    store.unpinAgent(workspaceKey, "agent-1");
+
+    state = useWorkspaceLayoutStore.getState();
+    expect(state.pinnedAgentIdsByWorkspace[workspaceKey]).toBeUndefined();
+    expect(Array.from(state.pinnedAgentIdsByWorkspace[otherWorkspaceKey as string] ?? [])).toEqual([
+      "agent-2",
+    ]);
+
+    const partialize = useWorkspaceLayoutStore.persist.getOptions().partialize;
+    expect(partialize).toBeTypeOf("function");
+    expect(partialize?.(state)).toEqual({
+      layoutByWorkspace: {},
+      splitSizesByWorkspace: {},
+    });
+  });
 });

packages/app/src/stores/workspace-layout-store.ts

@@ -53,6 +53,7 @@ export type { SplitGroup, SplitNode, SplitPane, WorkspaceLayout };
 interface WorkspaceLayoutStore {
   layoutByWorkspace: Record<string, WorkspaceLayout>;
   splitSizesByWorkspace: Record<string, Record<string, number[]>>;
+  pinnedAgentIdsByWorkspace: Record<string, Set<string>>;
   openTab: (workspaceKey: string, target: WorkspaceTabTarget) => string | null;
   closeTab: (workspaceKey: string, tabId: string) => void;
   focusTab: (workspaceKey: string, tabId: string) => void;
@@ -78,6 +79,8 @@ interface WorkspaceLayoutStore {
   focusPane: (workspaceKey: string, paneId: string) => void;
   resizeSplit: (workspaceKey: string, groupId: string, sizes: number[]) => void;
   reorderTabsInPane: (workspaceKey: string, paneId: string, tabIds: string[]) => void;
+  pinAgent: (workspaceKey: string, agentId: string) => void;
+  unpinAgent: (workspaceKey: string, agentId: string) => void;
 }
 
 const MAX_TREE_DEPTH = 4;
@@ -99,6 +102,7 @@ export const useWorkspaceLayoutStore = create<WorkspaceLayoutStore>()(
     (set, get) => ({
       layoutByWorkspace: {},
       splitSizesByWorkspace: {},
+      pinnedAgentIdsByWorkspace: {},
       openTab: (workspaceKey, target) => {
         const normalizedWorkspaceKey = trimNonEmpty(workspaceKey);
         const normalizedTarget = normalizeWorkspaceTabTarget(target);
@@ -385,6 +389,66 @@ export const useWorkspaceLayoutStore = create<WorkspaceLayoutStore>()(
           };
         });
       },
+      pinAgent: (workspaceKey, agentId) => {
+        const normalizedWorkspaceKey = trimNonEmpty(workspaceKey);
+        const normalizedAgentId = trimNonEmpty(agentId);
+        if (!normalizedWorkspaceKey || !normalizedAgentId) {
+          return;
+        }
+
+        set((state) => {
+          const currentPinnedAgentIds =
+            state.pinnedAgentIdsByWorkspace[normalizedWorkspaceKey] ?? null;
+          if (currentPinnedAgentIds?.has(normalizedAgentId)) {
+            return state;
+          }
+
+          const nextPinnedAgentIds = new Set(currentPinnedAgentIds ?? []);
+          nextPinnedAgentIds.add(normalizedAgentId);
+
+          return {
+            pinnedAgentIdsByWorkspace: {
+              ...state.pinnedAgentIdsByWorkspace,
+              [normalizedWorkspaceKey]: nextPinnedAgentIds,
+            },
+          };
+        });
+      },
+      unpinAgent: (workspaceKey, agentId) => {
+        const normalizedWorkspaceKey = trimNonEmpty(workspaceKey);
+        const normalizedAgentId = trimNonEmpty(agentId);
+        if (!normalizedWorkspaceKey || !normalizedAgentId) {
+          return;
+        }
+
+        set((state) => {
+          const currentPinnedAgentIds =
+            state.pinnedAgentIdsByWorkspace[normalizedWorkspaceKey] ?? null;
+          if (!currentPinnedAgentIds?.has(normalizedAgentId)) {
+            return state;
+          }
+
+          if (currentPinnedAgentIds.size === 1) {
+            const nextPinnedAgentIdsByWorkspace = {
+              ...state.pinnedAgentIdsByWorkspace,
+            };
+            delete nextPinnedAgentIdsByWorkspace[normalizedWorkspaceKey];
+            return {
+              pinnedAgentIdsByWorkspace: nextPinnedAgentIdsByWorkspace,
+            };
+          }
+
+          const nextPinnedAgentIds = new Set(currentPinnedAgentIds);
+          nextPinnedAgentIds.delete(normalizedAgentId);
+
+          return {
+            pinnedAgentIdsByWorkspace: {
+              ...state.pinnedAgentIdsByWorkspace,
+              [normalizedWorkspaceKey]: nextPinnedAgentIds,
+            },
+          };
+        });
+      },
     }),
     {
       name: "workspace-layout-state",