fix(cli): clarify prompt mode login guidance

.changeset/friendly-prompt-login.md

@@ -0,0 +1,5 @@
+---
+"@moonshot-ai/kimi-code": patch
+---
+
+Clarify the prompt-mode error when no model is configured by pointing users to the login flow.

apps/kimi-code/src/cli/run-prompt.ts

@@ -233,7 +233,9 @@ async function forcePromptPermission(
 function requireConfiguredModel(...models: readonly (string | undefined)[]): string {
   const model = configuredModel(...models);
   if (model === undefined) {
-    throw new Error('No model configured. Set default_model in config.toml.');
+    throw new Error(
+      'No model configured. Run `kimi` and use /login to sign in, then retry; or set default_model in config.toml.',
+    );
   }
   return model;
 }

apps/kimi-code/test/cli/run-prompt.test.ts

@@ -634,7 +634,9 @@ describe('runPrompt', () => {
         stdout: { write: vi.fn(() => true) },
         stderr: { write: vi.fn(() => true) },
       }),
-    ).rejects.toThrow('No model configured. Set default_model in config.toml.');
+    ).rejects.toThrow(
+      'No model configured. Run `kimi` and use /login to sign in, then retry; or set default_model in config.toml.',
+    );
 
     expect(mocks.harnessClose).toHaveBeenCalled();
   });