fix: finish exec tool failure landing (#52508) (thanks @martingarramon)

CHANGELOG.md

@@ -106,6 +106,7 @@ Docs: https://docs.openclaw.ai
 - Mattermost/threading: honor `replyToMode: "off"` for already-threaded inbound posts so threaded follow-ups can fall back to top-level replies when configured. (#52543) Thanks @RichardCao.
 - Telegram/replies: set `allow_sending_without_reply` on reply-targeted sends and media-error notices so deleted parent messages no longer drop otherwise valid replies. (#52524) Thanks @moltbot886.
 - Gateway/status: resolve env-backed `gateway.auth.*` SecretRefs before read-only probe auth checks so status no longer reports false probe failures when auth is configured through SecretRef. (#52513) Thanks @CodeForgeNet.
+- Agents/exec: return plain-text failed tool output for timeouts and other non-success exec outcomes so models no longer parrot raw JSON error payloads back to users. (#52508) Thanks @martingarramon.
 - CLI/startup: lazy-load channel add and root help startup paths to trim avoidable RSS and help latency on constrained hosts. (#46784) Thanks @vincentkoc.
 - CLI/onboarding: import static provider definitions directly for onboarding model/config helpers so those paths no longer pull provider discovery just for built-in defaults. (#47467) Thanks @vincentkoc.
 - CLI/configure: clarify fresh-setup memory-search warnings so they say semantic recall needs at least one embedding provider, and scope the initial model allowlist picker to the provider selected in configure. Thanks @vincentkoc.

src/agents/bash-tools.test.ts

@@ -462,11 +462,21 @@ describe("exec tool backgrounding", () => {
       allowBackground: false,
     });
     const result = await executeExecCommand(customBash, longDelayCmd);
-    const text = (result as { content: { text: string }[] }).content[0].text;
+    const text = readTextContent(result.content);
     expect(text).toMatch(/timed out/i);
     expect(text).toMatch(/re-run with a higher timeout/i);
-    const details = (result as { details: { status: string } }).details;
-    expect(details.status).toBe("failed");
+    const details = result.details as {
+      status?: string;
+      exitCode?: number | null;
+      durationMs?: number;
+      aggregated?: string;
+    };
+    expect(details).toMatchObject({
+      status: "failed",
+      exitCode: null,
+      aggregated: "",
+    });
+    expect(details.durationMs).toEqual(expect.any(Number));
   });
 
   it.each<DisallowedElevationCase>(DISALLOWED_ELEVATION_CASES)(