fix(cli): write agent exec plain output to stdout (#114043)

src/commands/agent-exec.test.ts

@@ -1,7 +1,9 @@
+import { execFile } from "node:child_process";
 import fs from "node:fs/promises";
 import os from "node:os";
 import path from "node:path";
 import { Readable } from "node:stream";
+import { promisify } from "node:util";
 import { afterEach, describe, expect, it, vi } from "vitest";
 import {
   ensureAuthProfileStore,
@@ -13,6 +15,7 @@ import type { RuntimeEnv } from "../runtime.js";
 import { agentExecCommand, classifyAgentExecResult, resolveAgentExecPrompt } from "./agent-exec.js";
 
 const tempRoots: string[] = [];
+const execFileAsync = promisify(execFile);
 
 async function makeTempRoot(prefix: string): Promise<string> {
   const root = await fs.mkdtemp(path.join(os.tmpdir(), prefix));
@@ -167,6 +170,44 @@ describe("agent exec strict result classification", () => {
 });
 
 describe("agent exec command composition", () => {
+  it("writes plain final text to stdout when diagnostics are routed to stderr", async () => {
+    const source = `
+      import { agentExecCommand } from "./src/commands/agent-exec.ts";
+      import { enableConsoleCapture, routeLogsToStderr } from "./src/logging.ts";
+      import { defaultRuntime } from "./src/runtime.ts";
+
+      routeLogsToStderr();
+      enableConsoleCapture();
+      const result = await agentExecCommand("inspect", {}, defaultRuntime, {
+        runAgent: async () => ({
+          payloads: [{ text: "india" }],
+          meta: {
+            durationMs: 1,
+            agentMeta: {
+              sessionId: "session-result",
+              provider: "openai",
+              model: "gpt-5.6-sol",
+            },
+          },
+        }),
+      });
+      process.exitCode = result.exitCode;
+    `;
+
+    const { stdout, stderr } = await execFileAsync(
+      process.execPath,
+      ["--import", "tsx", "--input-type=module", "--eval", source],
+      {
+        cwd: path.resolve(import.meta.dirname, "../.."),
+        encoding: "utf8",
+        env: { ...process.env, OPENCLAW_TEST_RUNTIME_LOG: "1" },
+      },
+    );
+
+    expect(stdout).toBe("india\n");
+    expect(stderr).not.toContain("india");
+  });
+
   it("treats invalid timeout syntax as an ordinary usage error", async () => {
     const { runtime } = createRuntime();
 

src/commands/agent-exec.ts

@@ -9,7 +9,7 @@ import type { EmbeddedAgentRunMeta } from "../agents/embedded-agent.js";
 import type { OpenClawConfig } from "../config/types.openclaw.js";
 import { formatErrorMessage } from "../infra/errors.js";
 import { parseStrictNonNegativeInteger } from "../infra/parse-finite-number.js";
-import { writeRuntimeJson, type RuntimeEnv } from "../runtime.js";
+import { writeRuntimeJson, writeRuntimeStdout, type RuntimeEnv } from "../runtime.js";
 
 const AGENT_EXEC_MESSAGE_MAX_BYTES = 4 * 1024 * 1024;
 const AGENT_EXEC_DEFAULT_TIMEOUT_SECONDS = 600;
@@ -365,7 +365,7 @@ function writeAgentExecOutput(
   if (json) {
     writeRuntimeJson(runtime, envelope);
   } else if (envelope.final) {
-    runtime.log(envelope.final);
+    writeRuntimeStdout(runtime, envelope.final);
   }
   if (!envelope.ok && envelope.error) {
     runtime.error(envelope.error.message);

src/runtime.test.ts

@@ -10,7 +10,12 @@ vi.mock("../packages/terminal-core/src/restore.js", () => ({
   restoreTerminalState: vi.fn(),
 }));
 
-import { createNonExitingRuntime, ExitError, writeRuntimeJson } from "./runtime.js";
+import {
+  createNonExitingRuntime,
+  ExitError,
+  writeRuntimeJson,
+  writeRuntimeStdout,
+} from "./runtime.js";
 
 describe("createNonExitingRuntime", () => {
   it("returns runtime with exit function", () => {
@@ -85,3 +90,32 @@ describe("writeRuntimeJson", () => {
     expect(runtime.log).toHaveBeenCalledWith('{"key":"value"}');
   });
 });
+
+describe("writeRuntimeStdout", () => {
+  it("uses the direct stdout writer when available", () => {
+    const runtime = {
+      log: vi.fn(),
+      error: vi.fn(),
+      exit: vi.fn(),
+      writeStdout: vi.fn(),
+      writeJson: vi.fn(),
+    };
+
+    writeRuntimeStdout(runtime, "plain output");
+
+    expect(runtime.writeStdout).toHaveBeenCalledWith("plain output");
+    expect(runtime.log).not.toHaveBeenCalled();
+  });
+
+  it("falls back to the runtime logger when no stdout writer is available", () => {
+    const runtime = {
+      log: vi.fn(),
+      error: vi.fn(),
+      exit: vi.fn(),
+    };
+
+    writeRuntimeStdout(runtime, "plain output");
+
+    expect(runtime.log).toHaveBeenCalledWith("plain output");
+  });
+});

src/runtime.ts

@@ -139,3 +139,11 @@ export function writeRuntimeJson(
   }
   runtime.log(JSON.stringify(value, null, space > 0 ? space : undefined));
 }
+
+export function writeRuntimeStdout(runtime: RuntimeEnv | OutputRuntimeEnv, value: string): void {
+  if (hasRuntimeOutputWriter(runtime)) {
+    runtime.writeStdout(value);
+    return;
+  }
+  runtime.log(value);
+}