fix(cli): preserve custom tool-progress payloads and honor final-only for goal summaries

- `tool_progress` JSON now carries `custom_kind`/`custom_data`, so stream-json
  clients keep structured `kind: "custom"` payloads (e.g. the MCP OAuth
  authorization URL) instead of an opaque `{"kind":"custom"}`.
- The headless `/goal` summary is suppressed on stdout under
  `--final-message-only`, matching the single-final-assistant-message contract
  (the goal status is still conveyed by the exit code).

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

@@ -287,8 +287,13 @@ async function runHeadlessGoal(
   } finally {
     unsubscribeGoalEvents();
     const snapshot = completedSnapshot ?? (await session.getGoal()).goal;
+    // The goal status is conveyed by the exit code; `--final-message-only` keeps
+    // stdout to the single final assistant message, so the JSON summary is
+    // suppressed in that mode (the text summary stays on stderr).
     if (outputFormat === 'stream-json') {
-      stdout.write(`${JSON.stringify(goalSummaryJson(snapshot))}\n`);
+      if (!finalOnly) {
+        stdout.write(`${JSON.stringify(goalSummaryJson(snapshot))}\n`);
+      }
     } else {
       stderr.write(`${formatGoalSummaryText(snapshot)}\n`);
     }
@@ -1284,6 +1289,10 @@ function toolProgressMessage(event: Extract<Event, { type: 'tool.progress' }>):
   };
   if (event.update.text !== undefined) message['text'] = event.update.text;
   if (event.update.percent !== undefined) message['percent'] = event.update.percent;
+  // `kind: 'custom'` updates (e.g. the MCP OAuth authorization URL) carry their
+  // payload here; keep it so stream-json clients get the structured signal.
+  if (event.update.customKind !== undefined) message['custom_kind'] = event.update.customKind;
+  if (event.update.customData !== undefined) message['custom_data'] = event.update.customData;
   return message;
 }
 

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

@@ -189,6 +189,27 @@ describe('runPrompt headless goal mode', () => {
     expect(stdout.text()).toContain('"status":"complete"');
   });
 
+  it('suppresses the JSON goal summary in final-message-only mode', async () => {
+    mocks.session.prompt.mockImplementationOnce(async () => {
+      for (const handler of mocks.eventHandlers) {
+        handler(mocks.mainEvent({ type: 'turn.started', turnId: 1, origin: { kind: 'user' } }));
+        handler(mocks.mainEvent({ type: 'assistant.delta', turnId: 1, delta: 'shipped' }));
+        handler(mocks.mainEvent({ type: 'turn.ended', turnId: 1, reason: 'completed' }));
+      }
+    });
+    const stdout = writer();
+    const stderr = writer();
+
+    await runPrompt(opts({ outputFormat: 'stream-json', finalMessageOnly: true }), 'test', {
+      stdout,
+      stderr,
+      process: { once: () => {}, off: () => {}, exit: () => undefined as never },
+    });
+
+    expect(stdout.text()).toBe('{"role":"assistant","content":"shipped"}\n');
+    expect(stdout.text()).not.toContain('goal.summary');
+  });
+
   it('sets a distinct exit code for a non-complete final status', async () => {
     mocks.session.getGoal.mockResolvedValue({ goal: snapshot({ status: 'blocked' }) } as never);
     const stdout = writer();

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

@@ -1523,6 +1523,37 @@ describe('runPrompt', () => {
     expect(stderr.text()).toBe('');
   });
 
+  it('preserves custom tool.progress payloads (e.g. MCP OAuth URL) in stream-json', async () => {
+    mocks.session.prompt.mockImplementationOnce(async () => {
+      for (const handler of mocks.eventHandlers) {
+        handler(mocks.mainEvent({ type: 'turn.started', turnId: 75, origin: { kind: 'user' } }));
+        handler(
+          mocks.mainEvent({
+            type: 'tool.progress',
+            turnId: 75,
+            toolCallId: 'tc_1',
+            update: {
+              kind: 'custom',
+              customKind: 'mcp.oauth.authorization_url',
+              customData: { serverName: 'fs', authorizationUrl: 'https://auth.example/x' },
+            },
+          }),
+        );
+        handler(mocks.mainEvent({ type: 'turn.ended', turnId: 75, reason: 'completed' }));
+      }
+    });
+    const stdout = writer();
+
+    await runPrompt(opts({ outputFormat: 'stream-json' }), '1.2.3-test', {
+      stdout,
+      stderr: writer(),
+    });
+
+    expect(stdout.text()).toContain(
+      '{"type":"tool_progress","tool_call_id":"tc_1","kind":"custom","custom_kind":"mcp.oauth.authorization_url","custom_data":{"serverName":"fs","authorizationUrl":"https://auth.example/x"}}',
+    );
+  });
+
   it('keeps tool.progress on stderr (not JSON) in text mode', async () => {
     mocks.session.prompt.mockImplementationOnce(async () => {
       for (const handler of mocks.eventHandlers) {