perf: trim tui startup and refresh work

src/tui/tui-session-actions.test.ts

@@ -190,6 +190,50 @@ describe("tui session actions", () => {
     expect(listSessions).toHaveBeenCalledTimes(2);
   });
 
+  it("skips UI work when session refresh metadata is unchanged", async () => {
+    const listSessions = vi.fn().mockResolvedValue({
+      ts: Date.now(),
+      path: "/tmp/sessions.json",
+      count: 1,
+      defaults: {},
+      sessions: [
+        {
+          key: "agent:main:main",
+          model: "sonnet-4.6",
+          modelProvider: "anthropic",
+          totalTokens: 42,
+          updatedAt: 200,
+        },
+      ],
+    });
+    const state = createBaseState({
+      sessionInfo: {
+        model: "sonnet-4.6",
+        modelProvider: "anthropic",
+        totalTokens: 42,
+        updatedAt: 100,
+      },
+    });
+    const updateFooter = vi.fn();
+    const updateAutocompleteProvider = vi.fn();
+    const requestRender = vi.fn();
+
+    const { refreshSessionInfo } = createTestSessionActions({
+      client: { listSessions } as unknown as TuiBackend,
+      state,
+      updateFooter,
+      updateAutocompleteProvider,
+      tui: { requestRender } as unknown as import("@earendil-works/pi-tui").TUI,
+    });
+
+    await refreshSessionInfo();
+
+    expect(state.sessionInfo.updatedAt).toBe(200);
+    expect(updateAutocompleteProvider).not.toHaveBeenCalled();
+    expect(updateFooter).not.toHaveBeenCalled();
+    expect(requestRender).not.toHaveBeenCalled();
+  });
+
   it("keeps patched model selection when a refresh returns an older snapshot", async () => {
     const listSessions = vi.fn().mockResolvedValue({
       ts: Date.now(),

src/tui/tui-session-actions.ts

@@ -49,6 +49,46 @@ type SessionInfoEntry = SessionInfo & {
   providerOverride?: string;
 };
 
+function thinkingLevelsEqual(
+  left?: Array<{ id: string; label: string }>,
+  right?: Array<{ id: string; label: string }>,
+): boolean {
+  if (left === right) {
+    return true;
+  }
+  if (!left || !right || left.length !== right.length) {
+    return false;
+  }
+  return left.every((level, index) => {
+    const other = right[index];
+    return other?.id === level.id && other.label === level.label;
+  });
+}
+
+function goalEquals(left: SessionInfo["goal"], right: SessionInfo["goal"]): boolean {
+  return left === right || JSON.stringify(left ?? null) === JSON.stringify(right ?? null);
+}
+
+function sessionInfoUiEquals(left: SessionInfo, right: SessionInfo): boolean {
+  return (
+    left.thinkingLevel === right.thinkingLevel &&
+    thinkingLevelsEqual(left.thinkingLevels, right.thinkingLevels) &&
+    left.fastMode === right.fastMode &&
+    left.verboseLevel === right.verboseLevel &&
+    left.traceLevel === right.traceLevel &&
+    left.reasoningLevel === right.reasoningLevel &&
+    left.model === right.model &&
+    left.modelProvider === right.modelProvider &&
+    left.contextTokens === right.contextTokens &&
+    left.inputTokens === right.inputTokens &&
+    left.outputTokens === right.outputTokens &&
+    left.totalTokens === right.totalTokens &&
+    left.responseUsage === right.responseUsage &&
+    left.displayName === right.displayName &&
+    goalEquals(left.goal, right.goal)
+  );
+}
+
 export function createSessionActions(context: SessionActionContext) {
   const {
     client,
@@ -225,10 +265,17 @@ export function createSessionActions(context: SessionActionContext) {
       next.model = selection.model;
     }
 
+    const previous = state.sessionInfo;
+    const uiChanged = !sessionInfoUiEquals(previous, next);
+    if (!uiChanged && previous.updatedAt === next.updatedAt) {
+      return;
+    }
     state.sessionInfo = next;
-    updateAutocompleteProvider();
-    updateFooter();
-    tui.requestRender();
+    if (uiChanged) {
+      updateAutocompleteProvider();
+      updateFooter();
+      tui.requestRender();
+    }
   };
 
   const runRefreshSessionInfo = async () => {

src/tui/tui.ts

@@ -29,7 +29,6 @@ import {
 import { getSlashCommands } from "./commands.js";
 import { ChatLog } from "./components/chat-log.js";
 import { CustomEditor } from "./components/custom-editor.js";
-import { GatewayChatClient } from "./gateway-chat.js";
 import { resolveLocalRunShutdownGraceMs } from "./local-run-shutdown.js";
 import { editorTheme, theme } from "./theme/theme.js";
 import type { TuiBackend } from "./tui-backend.js";
@@ -522,6 +521,8 @@ export async function runTui(opts: RunTuiOptions): Promise<TuiResult> {
   let dynamicSlashCommandsKey: string | null = null;
   let dynamicSlashCommandsInFlightKey: string | null = null;
   let dynamicSlashCommandsRequestId = 0;
+  let dynamicSlashCommandsReady = false;
+  let dynamicSlashCommandsRefreshTimer: ReturnType<typeof setTimeout> | null = null;
   let lastCtrlCAt = 0;
   let exitRequested = false;
   let exitResult: TuiResult = { exitReason: "exit" };
@@ -714,6 +715,7 @@ export async function runTui(opts: RunTuiOptions): Promise<TuiResult> {
     const { EmbeddedTuiBackend } = await import("./embedded-backend.js");
     client = new EmbeddedTuiBackend();
   } else {
+    const { GatewayChatClient } = await import("./gateway-chat.js");
     client = await GatewayChatClient.connect({
       url: opts.url,
       token: opts.token,
@@ -769,9 +771,19 @@ export async function runTui(opts: RunTuiOptions): Promise<TuiResult> {
     );
   };
 
+  const clearDynamicSlashCommandsRefreshTimer = () => {
+    if (!dynamicSlashCommandsRefreshTimer) {
+      return;
+    }
+    clearTimeout(dynamicSlashCommandsRefreshTimer);
+    dynamicSlashCommandsRefreshTimer = null;
+  };
+
   const refreshDynamicSlashCommands = () => {
+    clearDynamicSlashCommandsRefreshTimer();
     const key = resolveDynamicSlashCommandsKey();
     if (
+      !dynamicSlashCommandsReady ||
       !isConnected ||
       !client.listCommands ||
       dynamicSlashCommandsKey === key ||
@@ -807,9 +819,21 @@ export async function runTui(opts: RunTuiOptions): Promise<TuiResult> {
       });
   };
 
+  const scheduleDynamicSlashCommandsRefresh = () => {
+    if (
+      !dynamicSlashCommandsReady ||
+      dynamicSlashCommandsRefreshTimer ||
+      dynamicSlashCommandsKey === resolveDynamicSlashCommandsKey()
+    ) {
+      return;
+    }
+    dynamicSlashCommandsRefreshTimer = setTimeout(refreshDynamicSlashCommands, 0);
+    dynamicSlashCommandsRefreshTimer.unref?.();
+  };
+
   const updateAutocompleteProvider = () => {
     applyAutocompleteProvider();
-    refreshDynamicSlashCommands();
+    scheduleDynamicSlashCommandsRefresh();
   };
 
   tui.addChild(root);
@@ -1474,6 +1498,8 @@ export async function runTui(opts: RunTuiOptions): Promise<TuiResult> {
         4000,
       );
       tui.requestRender();
+      dynamicSlashCommandsReady = true;
+      scheduleDynamicSlashCommandsRefresh();
       if (!autoMessageSent && autoMessage) {
         autoMessageSent = true;
         await sendMessage(autoMessage);
@@ -1494,6 +1520,8 @@ export async function runTui(opts: RunTuiOptions): Promise<TuiResult> {
     dynamicSlashCommands = [];
     dynamicSlashCommandsKey = null;
     dynamicSlashCommandsInFlightKey = null;
+    dynamicSlashCommandsReady = false;
+    clearDynamicSlashCommandsRefreshTimer();
     dynamicSlashCommandsRequestId += 1;
     updateAutocompleteProvider();
     pauseStreamingWatchdog();