fix(cli): route plugin logs to stderr during --json output

src/cli/program/preaction.test.ts

@@ -1,5 +1,6 @@
 import { Command } from "commander";
 import { afterAll, afterEach, beforeAll, beforeEach, describe, expect, it, vi } from "vitest";
+import { loggingState } from "../../logging/state.js";
 import { setCommandJsonMode } from "./json-mode.js";
 
 const setVerboseMock = vi.fn();
@@ -58,6 +59,7 @@ let originalProcessArgv: string[];
 let originalProcessTitle: string;
 let originalNodeNoWarnings: string | undefined;
 let originalHideBanner: string | undefined;
+let originalForceStderr: boolean;
 
 beforeAll(async () => {
   ({ registerPreActionHooks } = await import("./preaction.js"));
@@ -76,6 +78,8 @@ beforeEach(() => {
   originalProcessTitle = process.title;
   originalNodeNoWarnings = process.env.NODE_NO_WARNINGS;
   originalHideBanner = process.env.OPENCLAW_HIDE_BANNER;
+  originalForceStderr = loggingState.forceConsoleToStderr;
+  loggingState.forceConsoleToStderr = false;
   delete process.env.NODE_NO_WARNINGS;
   delete process.env.OPENCLAW_HIDE_BANNER;
 });
@@ -83,6 +87,7 @@ beforeEach(() => {
 afterEach(() => {
   process.argv = originalProcessArgv;
   process.title = originalProcessTitle;
+  loggingState.forceConsoleToStderr = originalForceStderr;
   if (originalNodeNoWarnings === undefined) {
     delete process.env.NODE_NO_WARNINGS;
   } else {
@@ -340,6 +345,39 @@ describe("registerPreActionHooks", () => {
     expect(ensureConfigReadyMock).not.toHaveBeenCalled();
   });
 
+  it("routes logs to stderr during plugin loading in --json mode and restores after", async () => {
+    let stderrDuringPluginLoad = false;
+    ensurePluginRegistryLoadedMock.mockImplementation(() => {
+      stderrDuringPluginLoad = loggingState.forceConsoleToStderr;
+    });
+
+    await runPreAction({
+      parseArgv: ["agents"],
+      processArgv: ["node", "openclaw", "agents", "--json"],
+    });
+
+    expect(ensurePluginRegistryLoadedMock).toHaveBeenCalled();
+    expect(stderrDuringPluginLoad).toBe(true);
+    // Flag must be restored after plugin loading completes
+    expect(loggingState.forceConsoleToStderr).toBe(false);
+  });
+
+  it("does not route logs to stderr during plugin loading without --json", async () => {
+    let stderrDuringPluginLoad = false;
+    ensurePluginRegistryLoadedMock.mockImplementation(() => {
+      stderrDuringPluginLoad = loggingState.forceConsoleToStderr;
+    });
+
+    await runPreAction({
+      parseArgv: ["agents"],
+      processArgv: ["node", "openclaw", "agents"],
+    });
+
+    expect(ensurePluginRegistryLoadedMock).toHaveBeenCalled();
+    expect(stderrDuringPluginLoad).toBe(false);
+    expect(loggingState.forceConsoleToStderr).toBe(false);
+  });
+
   beforeAll(() => {
     program = buildProgram();
     const hooks = (

src/cli/program/preaction.ts

@@ -3,6 +3,7 @@ import { setVerbose } from "../../globals.js";
 import { isTruthyEnvValue } from "../../infra/env.js";
 import { routeLogsToStderr } from "../../logging/console.js";
 import type { LogLevel } from "../../logging/levels.js";
+import { loggingState } from "../../logging/state.js";
 import { defaultRuntime } from "../../runtime.js";
 import { getCommandPathWithRootOptions, getVerboseFlag, hasHelpOrVersion } from "../argv.js";
 import { emitCliBanner } from "../banner.js";
@@ -138,10 +139,21 @@ export function registerPreActionHooks(program: Command, programVersion: string)
       commandPath,
       ...(jsonOutputMode ? { suppressDoctorStdout: true } : {}),
     });
-    // Load plugins for commands that need channel access
+<<<<<<< HEAD
+    // Load plugins for commands that need channel access.
+    // When --json output is active, temporarily route logs to stderr so plugin
+    // registration messages don't corrupt the JSON payload on stdout.
     if (shouldLoadPluginsForCommand(commandPath, jsonOutputMode)) {
       const { ensurePluginRegistryLoaded } = await loadPluginRegistryModule();
-      ensurePluginRegistryLoaded({ scope: resolvePluginRegistryScope(commandPath) });
+      const prev = loggingState.forceConsoleToStderr;
+      if (jsonOutputMode) {
+        loggingState.forceConsoleToStderr = true;
+      }
+      try {
+        ensurePluginRegistryLoaded({ scope: resolvePluginRegistryScope(commandPath) });
+      } finally {
+        loggingState.forceConsoleToStderr = prev;
+      }
     }
   });
 }