feat(tui): add stats display mode for live thinking

.changeset/thinking-live-stats.md

@@ -0,0 +1,5 @@
+---
+"@moonshot-ai/kimi-code": patch
+---
+
+Add a `thinking_live_display` TUI preference. Set it to `"stats"` in `tui.toml` to replace the scrolling thinking preview with an approximate token count and elapsed thinking time, leaving a one-line "Thought for …" summary when thinking finishes.

apps/kimi-code/src/tui/commands/reload.ts

@@ -70,6 +70,7 @@ export async function applyReloadedTuiConfig(
     disablePasteBurst: config.disablePasteBurst,
     renderLatex: config.renderLatex,
     cacheExpiryHint: config.cacheExpiryHint,
+    thinkingLiveDisplay: config.thinkingLiveDisplay,
     notifications: config.notifications,
     upgrade: config.upgrade,
     statusLine: config.statusLine,

apps/kimi-code/src/tui/components/messages/thinking.ts

@@ -3,10 +3,16 @@
  * Supports live in-place updates while thinking streams, then finalizes
  * without replacing the component.
  * Supports expand/collapse via Ctrl+O (shared with tool output).
+ *
+ * The live display has two modes (tui.toml `thinking_live_display`):
+ * 'preview' scrolls the last few streamed lines; 'stats' hides the text and
+ * shows an approximate token count plus the elapsed thinking time instead,
+ * leaving a one-line "Thought for …" summary once thinking finishes.
  */
 
 import { Text, truncateToWidth, type Component, type TUI } from '@moonshot-ai/pi-tui';
 
+import type { ThinkingLiveDisplay } from '#/tui/config';
 import {
   BRAILLE_SPINNER_FRAMES,
   BRAILLE_SPINNER_INTERVAL_MS,
@@ -16,13 +22,17 @@ import {
 import { STATUS_BULLET } from '#/tui/constant/symbols';
 import { currentTheme } from '#/tui/theme';
 import { isRenderCacheEnabled } from '#/tui/utils/render-cache';
+import { formatTokenCount } from '#/utils/usage/usage-format';
 
 export type ThinkingRenderMode = 'live' | 'finalized';
 
 export class ThinkingComponent implements Component {
   private text: string;
   private showMarker: boolean;
   private mode: ThinkingRenderMode;
+  private readonly liveDisplay: ThinkingLiveDisplay;
+  private readonly startedAt: number;
+  private finalizedElapsedSeconds: number | undefined;
   private expanded = false;
   private readonly ui: TUI | undefined;
   private spinnerFrame = 0;
@@ -40,11 +50,14 @@ export class ThinkingComponent implements Component {
     showMarker: boolean = true,
     mode: ThinkingRenderMode = 'finalized',
     ui?: TUI,
+    liveDisplay: ThinkingLiveDisplay = 'preview',
   ) {
     this.text = text;
     this.showMarker = showMarker;
     this.mode = mode;
     this.ui = ui;
+    this.liveDisplay = liveDisplay;
+    this.startedAt = Date.now();
     this.textComponent = new Text(this.styled(text), 0, 0);
     if (mode === 'live') {
       this.startSpinner();
@@ -73,6 +86,7 @@ export class ThinkingComponent implements Component {
 
   finalize(): void {
     this.mode = 'finalized';
+    this.finalizedElapsedSeconds = Math.floor((Date.now() - this.startedAt) / 1000);
     this.markRenderDirty();
     this.stopSpinner();
   }
@@ -97,22 +111,46 @@ export class ThinkingComponent implements Component {
     }
 
     const contentWidth = Math.max(1, width - MESSAGE_INDENT.length);
-    const contentLines = this.text.length > 0 ? this.textComponent.render(contentWidth) : [''];
+    // Stats mode hides the text unless explicitly expanded, so skip the re-wrap.
+    const showContent = this.liveDisplay === 'preview' || this.expanded;
+    const contentLines =
+      showContent && this.text.length > 0 ? this.textComponent.render(contentWidth) : [''];
 
     let rendered: string[];
     if (this.mode === 'live') {
-      const visibleLines =
-        contentLines.length > THINKING_PREVIEW_LINES
-          ? contentLines.slice(contentLines.length - THINKING_PREVIEW_LINES)
-          : contentLines;
       const spinner = currentTheme.fg(
         'textDim',
         `${BRAILLE_SPINNER_FRAMES[this.spinnerFrame] ?? BRAILLE_SPINNER_FRAMES[0]} `,
       );
+      if (this.liveDisplay === 'stats') {
+        // No tokenizer is available to the client, and reasoning-token usage
+        // only arrives at step end — so the live count is a chars/4 estimate.
+        const approxTokens = Math.ceil(this.text.length / 4);
+        const elapsedSeconds = Math.floor((Date.now() - this.startedAt) / 1000);
+        const stats = `(~${formatTokenCount(approxTokens)} tokens · ${formatThinkingDuration(elapsedSeconds)})`;
+        rendered = ['', spinner + currentTheme.fg('textDim', `thinking... ${stats}`)];
+      } else {
+        const visibleLines =
+          contentLines.length > THINKING_PREVIEW_LINES
+            ? contentLines.slice(contentLines.length - THINKING_PREVIEW_LINES)
+            : contentLines;
+        rendered = [
+          '',
+          spinner + currentTheme.fg('textDim', 'thinking...'),
+          ...visibleLines.map((line) => MESSAGE_INDENT + line),
+        ];
+      }
+    } else if (this.liveDisplay === 'stats' && !this.expanded) {
+      // Stats mode leaves a one-line summary instead of the content preview;
+      // ctrl+o expands into the full text.
+      const p = this.showMarker ? currentTheme.fg('textDim', STATUS_BULLET) : MESSAGE_INDENT;
+      const hint = this.text.length > 0 ? ' (ctrl+o to expand)' : '';
+      const summary = `Thought for ${formatThinkingDuration(this.finalizedElapsedSeconds ?? 0)}${hint}`;
+      // Both prefixes occupy two cells (STATUS_BULLET is '● ').
+      const summaryWidth = Math.max(0, width - MESSAGE_INDENT.length);
       rendered = [
         '',
-        spinner + currentTheme.fg('textDim', 'thinking...'),
-        ...visibleLines.map((line) => MESSAGE_INDENT + line),
+        p + currentTheme.fg('textDim', truncateToWidth(summary, summaryWidth, '…')),
       ];
     } else {
       const lines: string[] = [''];
@@ -158,3 +196,13 @@ export class ThinkingComponent implements Component {
     this.spinnerInterval = undefined;
   }
 }
+
+/** Compact elapsed time for the live stats line: 10s, 1m12s, 5h3m33s. */
+function formatThinkingDuration(totalSeconds: number): string {
+  const seconds = totalSeconds % 60;
+  const minutes = Math.floor(totalSeconds / 60) % 60;
+  const hours = Math.floor(totalSeconds / 3600);
+  if (hours > 0) return `${String(hours)}h${String(minutes)}m${String(seconds)}s`;
+  if (minutes > 0) return `${String(minutes)}m${String(seconds)}s`;
+  return `${String(seconds)}s`;
+}

apps/kimi-code/src/tui/config.ts

@@ -33,6 +33,9 @@ export const UpgradePreferencesSchema = z.object({
 export const STATUS_LINE_ITEMS = ['mode', 'goal', 'model', 'tasks', 'cwd', 'git', 'tips'] as const;
 export type StatusLineItem = (typeof STATUS_LINE_ITEMS)[number];
 
+export const ThinkingLiveDisplaySchema = z.enum(['preview', 'stats']);
+export type ThinkingLiveDisplay = z.infer<typeof ThinkingLiveDisplaySchema>;
+
 export const StatusLineFileConfigSchema = z.object({
   items: z.array(z.string()).optional(),
   command: z.string().optional(),
@@ -56,6 +59,7 @@ export const TuiConfigFileSchema = z.object({
   render_latex: z.boolean().optional(),
   disable_paste_burst: z.boolean().optional(),
   cache_expiry_hint: z.boolean().optional(),
+  thinking_live_display: ThinkingLiveDisplaySchema.optional(),
   editor: z
     .object({
       command: z.string().optional(),
@@ -84,6 +88,9 @@ export const TuiConfigSchema = z.object({
   /** Present in every normalized config; optional only so hand-built test
    * fixtures from before this field existed still typecheck. */
   cacheExpiryHint: z.boolean().optional(),
+  /** Present in every normalized config; optional only so hand-built test
+   * fixtures from before this field existed still typecheck. */
+  thinkingLiveDisplay: ThinkingLiveDisplaySchema.optional(),
   editorCommand: z.string().nullable(),
   notifications: NotificationsConfigSchema,
   upgrade: UpgradePreferencesSchema,
@@ -111,6 +118,7 @@ export const DEFAULT_TUI_CONFIG: TuiConfig = TuiConfigSchema.parse({
   renderLatex: true,
   disablePasteBurst: false,
   cacheExpiryHint: true,
+  thinkingLiveDisplay: 'preview',
   editorCommand: null,
   notifications: DEFAULT_NOTIFICATIONS_CONFIG,
   upgrade: DEFAULT_UPGRADE_PREFERENCES,
@@ -198,6 +206,8 @@ export function normalizeTuiConfig(
     renderLatex: config.render_latex ?? DEFAULT_TUI_CONFIG.renderLatex,
     disablePasteBurst: config.disable_paste_burst ?? DEFAULT_TUI_CONFIG.disablePasteBurst,
     cacheExpiryHint: config.cache_expiry_hint ?? DEFAULT_TUI_CONFIG.cacheExpiryHint,
+    thinkingLiveDisplay:
+      config.thinking_live_display ?? DEFAULT_TUI_CONFIG.thinkingLiveDisplay,
     editorCommand: command === undefined || command.length === 0 ? null : command,
     notifications: {
       enabled: config.notifications?.enabled ?? DEFAULT_NOTIFICATIONS_CONFIG.enabled,
@@ -248,6 +258,7 @@ theme = "${escapeTomlBasicString(config.theme)}" # "auto" | "dark" | "light" | c
 render_latex = ${String(config.renderLatex !== false)} # false keeps LaTeX math in assistant messages as raw source
 disable_paste_burst = ${String(config.disablePasteBurst)} # true disables non-bracketed paste-burst fallback
 cache_expiry_hint = ${String(config.cacheExpiryHint !== false)} # false disables the "cache expired" dialog on resume / idle submit
+thinking_live_display = "${config.thinkingLiveDisplay ?? 'preview'}" # "preview" scrolls the last lines while thinking streams; "stats" shows ~tokens and elapsed time
 
 [editor]
 command = "${escapeTomlBasicString(config.editorCommand ?? '')}" # Empty uses $VISUAL / $EDITOR

apps/kimi-code/src/tui/controllers/streaming-ui.ts

@@ -641,6 +641,7 @@ export class StreamingUIController {
         true,
         'live',
         state.ui,
+        state.appState.thinkingLiveDisplay ?? 'preview',
       );
       if (state.toolOutputExpanded) this._activeThinkingComponent.setExpanded(true);
       state.transcriptContainer.addChild(this._activeThinkingComponent);

apps/kimi-code/src/tui/kimi-tui.ts

@@ -258,6 +258,7 @@ function createInitialAppState(input: KimiTUIStartupInput): AppState {
     disablePasteBurst: input.tuiConfig.disablePasteBurst,
     renderLatex: input.tuiConfig.renderLatex,
     cacheExpiryHint: input.tuiConfig.cacheExpiryHint,
+    thinkingLiveDisplay: input.tuiConfig.thinkingLiveDisplay,
     notifications: input.tuiConfig.notifications,
     upgrade: input.tuiConfig.upgrade,
     statusLine: input.tuiConfig.statusLine,

apps/kimi-code/src/tui/types.ts

@@ -9,7 +9,12 @@ import type {
   ToolInputDisplay,
 } from '@moonshot-ai/kimi-code-sdk';
 
-import type { NotificationsConfig, StatusLineConfig, UpgradePreferences } from './config';
+import type {
+  NotificationsConfig,
+  StatusLineConfig,
+  ThinkingLiveDisplay,
+  UpgradePreferences,
+} from './config';
 import type { PendingApproval, PendingQuestion } from './reverse-rpc/types';
 import type { ColorToken, ThemeName } from './theme';
 
@@ -75,6 +80,8 @@ export interface AppState {
   renderLatex?: boolean;
   /** Mirrors the TUI config toggle; defaults to true when absent from older fixtures. */
   cacheExpiryHint?: boolean;
+  /** Live thinking display mode; defaults to 'preview' when absent from older fixtures. */
+  thinkingLiveDisplay?: ThinkingLiveDisplay;
   notifications: NotificationsConfig;
   upgrade: UpgradePreferences;
   /** Footer status line customization from tui.toml; absent means the default layout. */

apps/kimi-code/test/tui/components/messages/thinking.test.ts

@@ -89,4 +89,73 @@ describe('ThinkingComponent', () => {
       expect(visibleWidth(line)).toBeLessThanOrEqual(37);
     }
   });
+
+  it('shows approx tokens and elapsed time instead of content in live stats mode', () => {
+    const component = new ThinkingComponent(longThinking, true, 'live', undefined, 'stats');
+    const out = strip(component.render(80).join('\n'));
+
+    expect(out).toContain('⠋ thinking...');
+    // longThinking is 41 chars → ceil(41 / 4) = 11 approximate tokens.
+    expect(out).toContain('~11 tokens');
+    expect(out).toContain('0s');
+    expect(out).not.toContain('line6');
+    expect(out).not.toContain('line7');
+  });
+
+  it('ticks the elapsed time in live stats mode', () => {
+    vi.useFakeTimers();
+    const component = new ThinkingComponent('working it out', true, 'live', undefined, 'stats');
+
+    vi.advanceTimersByTime(72_000);
+    component.invalidate();
+    expect(strip(component.render(80).join('\n'))).toContain('1m12s');
+
+    vi.advanceTimersByTime(18_213_000 - 72_000);
+    component.invalidate();
+    expect(strip(component.render(80).join('\n'))).toContain('5h3m33s');
+
+    vi.useRealTimers();
+  });
+
+  it('finalizes stats mode into a "Thought for" summary line', () => {
+    const component = new ThinkingComponent(longThinking, true, 'live', undefined, 'stats');
+
+    component.finalize();
+
+    const out = strip(component.render(80).join('\n'));
+    expect(out).toContain(`${STATUS_BULLET}Thought for 0s`);
+    expect(out).toContain('(ctrl+o to expand)');
+    expect(out).not.toContain('line1');
+    expect(out).not.toContain('line7');
+  });
+
+  it('freezes the elapsed time in the stats summary on finalize', () => {
+    vi.useFakeTimers();
+    const component = new ThinkingComponent('working it out', true, 'live', undefined, 'stats');
+
+    vi.advanceTimersByTime(72_000);
+    component.finalize();
+    expect(strip(component.render(80).join('\n'))).toContain('Thought for 1m12s');
+
+    vi.advanceTimersByTime(60_000);
+    component.invalidate();
+    expect(strip(component.render(80).join('\n'))).toContain('Thought for 1m12s');
+
+    vi.useRealTimers();
+  });
+
+  it('expands a finalized stats summary into the full thinking text', () => {
+    const component = new ThinkingComponent(longThinking, true, 'live', undefined, 'stats');
+    component.finalize();
+
+    component.setExpanded(true);
+    const expanded = strip(component.render(80).join('\n'));
+    expect(expanded).toContain('line7');
+    expect(expanded).not.toContain('Thought for');
+
+    component.setExpanded(false);
+    const collapsed = strip(component.render(80).join('\n'));
+    expect(collapsed).toContain('Thought for 0s');
+    expect(collapsed).not.toContain('line7');
+  });
 });

apps/kimi-code/test/tui/config.test.ts

@@ -35,6 +35,7 @@ describe('TUI config', () => {
     expect(text).toContain('Client preferences for kimi-code.');
     expect(text).toContain('theme = "auto"');
     expect(text).toContain('cache_expiry_hint = true');
+    expect(text).toContain('thinking_live_display = "preview"');
     expect(text).toContain('command = ""');
     expect(text).toContain('[upgrade]');
     expect(text).toContain('auto_install = true');
@@ -63,6 +64,7 @@ auto_install = false
       renderLatex: true,
       disablePasteBurst: false,
       cacheExpiryHint: true,
+      thinkingLiveDisplay: 'preview',
       editorCommand: 'code --wait',
       notifications: { enabled: false, condition: 'always' },
       upgrade: { autoInstall: false },
@@ -98,6 +100,16 @@ cache_expiry_hint = false
     expect(config.cacheExpiryHint).toBe(false);
   });
 
+  it('defaults thinking_live_display to preview and parses stats', () => {
+    expect(parseTuiConfig('').thinkingLiveDisplay).toBe('preview');
+
+    const config = parseTuiConfig(`
+thinking_live_display = "stats"
+`);
+
+    expect(config.thinkingLiveDisplay).toBe('stats');
+  });
+
   it('normalizes an empty editor command to auto-detect', () => {
     const config = parseTuiConfig(`
 [editor]
@@ -109,6 +121,7 @@ command = "   "
       renderLatex: true,
       disablePasteBurst: false,
       cacheExpiryHint: true,
+      thinkingLiveDisplay: 'preview',
       editorCommand: null,
       notifications: { enabled: true, condition: 'unfocused' },
       upgrade: { autoInstall: true },
@@ -156,6 +169,7 @@ command = "   "
       renderLatex: true,
       disablePasteBurst: false,
       cacheExpiryHint: true,
+      thinkingLiveDisplay: 'preview',
       editorCommand: 'vim',
       notifications: { enabled: false, condition: 'always' },
       upgrade: { autoInstall: false },

docs/en/configuration/config-files.md

@@ -472,6 +472,7 @@ Alongside `config.toml`, the CLI keeps terminal-UI and client preferences in a c
 | `render_latex` | `boolean` | `true` | Render LaTeX math expressions (`$…$`, `$$…$$`) in Markdown messages as Unicode text; `false` keeps the raw source |
 | `disable_paste_burst` | `boolean` | `false` | Disable the non-bracketed paste-burst fallback that keeps rapid multi-line pastes from submitting line by line |
 | `cache_expiry_hint` | `boolean` | `true` | Show a dialog when resuming a long-idle session or submitting after a long idle stretch, warning that the context cache has likely expired and offering to compact or start a new session (v2 engine only) |
+| `thinking_live_display` | `string` | `preview` | What to show while thinking streams: `preview` scrolls the last lines of the thinking text; `stats` hides the text and shows an approximate token count plus the elapsed thinking time instead, leaving a one-line "Thought for …" summary when thinking finishes (Ctrl-O expands the full text) |
 | `[editor].command` | `string` | `""` | External editor command for composing long input; empty falls back to `$VISUAL` / `$EDITOR` |
 | `[notifications].enabled` | `boolean` | `true` | Whether desktop notifications are sent |
 | `[notifications].notification_condition` | `string` | `unfocused` | When to notify: `unfocused` (only when the terminal is not focused) or `always` |
@@ -485,6 +486,7 @@ theme = "auto" # "auto" | "dark" | "light" | custom theme name
 render_latex = true # false keeps LaTeX math in messages as raw source
 disable_paste_burst = false # true disables non-bracketed paste-burst fallback
 cache_expiry_hint = true # false disables the "cache expired" dialog on resume / idle submit
+thinking_live_display = "preview" # "preview" scrolls the last lines while thinking streams; "stats" shows ~tokens and elapsed time
 
 [editor]
 command = "" # empty uses $VISUAL / $EDITOR

docs/zh/configuration/config-files.md

@@ -471,6 +471,7 @@ MCP server 的声明配置写在 `~/.kimi-code/mcp.json` 或项目内 `.kimi-cod
 | `render_latex` | `boolean` | `true` | 将 Markdown 消息中的 LaTeX 公式（`$…$`、`$$…$$`）渲染为 Unicode 文本；`false` 则保留原始源码 |
 | `disable_paste_burst` | `boolean` | `false` | 禁用非 bracketed paste 的粘贴突发兜底；默认开启，避免快速多行粘贴被逐行提交 |
 | `cache_expiry_hint` | `boolean` | `true` | resume 长时间未活动的会话、或长时间空闲后发送消息时，若上下文缓存可能已过期则弹出提醒，可选择先压缩或新建会话（仅 v2 引擎） |
+| `thinking_live_display` | `string` | `preview` | Thinking 流式输出时的实时显示方式：`preview` 滚动展示思考内容的末尾几行；`stats` 隐藏正文，改为显示估算的 token 数和已用时间，思考结束后保留一行 "Thought for …" 摘要（Ctrl-O 可展开全文） |
 | `[editor].command` | `string` | `""` | 编写长输入用的外部编辑器命令；留空则回退到 `$VISUAL` / `$EDITOR` |
 | `[notifications].enabled` | `boolean` | `true` | 是否发送桌面通知 |
 | `[notifications].notification_condition` | `string` | `unfocused` | 何时通知：`unfocused`（仅终端失去焦点时）或 `always`（总是） |
@@ -484,6 +485,7 @@ theme = "auto" # "auto" | "dark" | "light" | 自定义主题名
 render_latex = true # false 表示消息中的 LaTeX 公式保留原始源码
 disable_paste_burst = false # true 表示禁用非 bracketed paste 的粘贴突发兜底
 cache_expiry_hint = true # false 表示关闭 resume / 空闲提交时的"缓存已过期"提醒弹窗
+thinking_live_display = "preview" # "preview" 滚动展示思考内容末尾几行；"stats" 显示估算 token 数和已用时间
 
 [editor]
 command = "" # 留空则使用 $VISUAL / $EDITOR