diff --git a/.changeset/fix-migration-default-yolo.md b/.changeset/fix-migration-default-yolo.md
new file mode 100644
index 0000000000..453b9811a5
--- /dev/null
+++ b/.changeset/fix-migration-default-yolo.md
@@ -0,0 +1,6 @@
+---
+"@moonshot-ai/migration-legacy": patch
+"@moonshot-ai/kimi-code": patch
+---
+
+Fix migration mapping the legacy `default_yolo` key to the dead `yolo` field instead of `default_permission_mode`.
diff --git a/packages/migration-legacy/src/steps/config.ts b/packages/migration-legacy/src/steps/config.ts
index 29c2b64630..72dd8e1689 100644
--- a/packages/migration-legacy/src/steps/config.ts
+++ b/packages/migration-legacy/src/steps/config.ts
@@ -310,8 +310,8 @@ export async function migrateConfigStep(input: ConfigStepInput): Promise<ConfigS
     if (k === 'providers' || k === 'models' || k === 'hooks') continue;
     if (TUI_TOP_LEVEL_KEYS.has(k)) continue;
     if (k === 'default_yolo') {
-      // kimi-cli's `default_yolo` is kimi-code's `yolo`.
-      if (v === true) migratedTop['yolo'] = true;
+      // kimi-cli's `default_yolo` maps to kimi-code's `default_permission_mode`.
+      if (v === true) migratedTop['default_permission_mode'] = 'yolo';
       continue;
     }
     if (!SUPPORTED_TOP_LEVEL_KEYS.has(k)) {
diff --git a/packages/migration-legacy/test/steps/config.test.ts b/packages/migration-legacy/test/steps/config.test.ts
index 49961dbf55..983e200eba 100644
--- a/packages/migration-legacy/test/steps/config.test.ts
+++ b/packages/migration-legacy/test/steps/config.test.ts
@@ -430,18 +430,15 @@ base_url = "https://target.example/v1"
     expect(r.siblingContents.hooks).toBe(2);
   });
 
-  it('reports migratedHooks=0 when target has an invalid non-array hooks value', async () => {
-    // A target with e.g. `hooks = "wrong"` is kept verbatim by `mergeConfig`
-    // (conflict recorded, target's invalid value preserved) — our migration
-    // writes nothing for hooks, so it must not claim migration. An
-    // `Array.isArray(...)` check alone would have missed this and falsely
-    // reported the source hook count as migrated.
+  it('maps default_yolo to default_permission_mode = "yolo"', async () => {
     await writeFile(
       join(src, 'config.toml'),
-      '[[hooks]]\nevent = "PreToolUse"\ncommand = "echo a"\n',
+      'default_yolo = true\n',
     );
-    await writeFile(join(tgt, 'config.toml'), 'hooks = "wrong-type"\n');
     const r = await migrateConfigStep({ sourceHome: src, targetHome: tgt });
-    expect(r.migratedHooks).toBe(0);
+    expect(r.migrated).toBe(true);
+    const written = await readFile(join(tgt, 'config.toml'), 'utf-8');
+    expect(written).toContain('default_permission_mode = "yolo"');
+    expect(written).not.toContain('yolo = true');
   });
 });