diff --git a/.changeset/fix-session-picker-narrow-terminal.md b/.changeset/fix-session-picker-narrow-terminal.md
new file mode 100644
index 00000000..8376138e
--- /dev/null
+++ b/.changeset/fix-session-picker-narrow-terminal.md
@@ -0,0 +1,5 @@
+---
+"@moonshot-ai/kimi-code": patch
+---
+
+Fix a crash in the `/sessions` picker on very narrow terminals (`Rendered line exceeds terminal width`). Long session ids, the inline time / `(current)` badge, and long prompts could be drawn past the terminal edge; every rendered line is now clamped to the terminal width so the picker degrades gracefully instead of crashing.
diff --git a/apps/kimi-code/src/tui/components/dialogs/session-picker.ts b/apps/kimi-code/src/tui/components/dialogs/session-picker.ts
index da1a139e..29053e64 100644
--- a/apps/kimi-code/src/tui/components/dialogs/session-picker.ts
+++ b/apps/kimi-code/src/tui/components/dialogs/session-picker.ts
@@ -126,6 +126,16 @@ export class SessionPickerComponent extends Container implements Focusable {
   }
 
   override render(width: number): string[] {
+    return this.renderLines(width).map((line) => truncateToWidth(line, width, ELLIPSIS));
+  }
+
+  // Builds the raw lines; `render()` applies a final width clamp so no line
+  // can ever exceed the terminal width. The per-line budgets below keep the
+  // layout tidy at normal widths, but on a very narrow terminal those budgets
+  // floor at a minimum and the trailing time/badge are appended in full, so
+  // the clamp in `render()` is what guarantees the renderer's invariant and
+  // prevents the "Rendered line exceeds terminal width" crash (issue #240).
+  private renderLines(width: number): string[] {
     const colors = this.colors;
     const lines: string[] = [chalk.hex(colors.primary)('─'.repeat(width))];
 
@@ -222,8 +232,9 @@ export class SessionPickerComponent extends Container implements Focusable {
     if (badge.length > 0) header += '  ' + chalk.hex(colors.success)(badge);
     const card: string[] = [header];
 
-    // Session id is rendered in full (no truncation). The directory wraps to
-    // its own line if it would push past the terminal edge.
+    // Session id is rendered in full at normal widths (the final clamp in
+    // `render()` truncates it only when the terminal is narrower than the id).
+    // The directory wraps to its own line if it would push past the edge.
     const fullId = session.id;
     const idWidth = visibleWidth(fullId);
     const metaGap = '   ';
diff --git a/apps/kimi-code/test/tui/components/dialogs/session-picker.test.ts b/apps/kimi-code/test/tui/components/dialogs/session-picker.test.ts
index c8e91963..c2608d5c 100644
--- a/apps/kimi-code/test/tui/components/dialogs/session-picker.test.ts
+++ b/apps/kimi-code/test/tui/components/dialogs/session-picker.test.ts
@@ -261,4 +261,41 @@ describe('SessionPickerComponent', () => {
       }
     }
   });
+
+  // Regression for #240: a long session id, the inline time + "(current)"
+  // badge, and a long prompt all used to be appended past the terminal edge,
+  // which crashed the renderer with "Rendered line exceeds terminal width" on
+  // very narrow terminals.
+  it('never renders a line wider than the terminal, even on tiny widths (#240)', () => {
+    const now = new Date('2026-05-11T12:00:00.000Z').getTime();
+    vi.spyOn(Date, 'now').mockReturnValue(now);
+
+    const id = 'ses_fbe574f3-572d-487f-9fa0-d09694f599d4';
+    const component = new SessionPickerComponent({
+      sessions: [
+        {
+          id,
+          title: '现在要重构一下 sessions 列表，让 UI 更好看一些',
+          last_prompt: 'please redesign the picker UI to be much nicer than before',
+          work_dir: '/Users/getlong/Development/cesiumdb',
+          updated_at: now - 5 * 60 * 1000,
+          metadata: { imported_from_kimi_cli: true },
+        },
+      ],
+      loading: false,
+      currentSessionId: id,
+      colors: getColorPalette('dark'),
+      onSelect: vi.fn(),
+      onCancel: vi.fn(),
+    });
+
+    for (let width = 10; width <= 60; width++) {
+      const lines = component.render(width);
+      for (const [idx, line] of lines.entries()) {
+        expect(visibleWidth(line), `width=${String(width)} line#${String(idx)}`).toBeLessThanOrEqual(
+          width,
+        );
+      }
+    }
+  });
 });