Noticed the real bug next door and told no one
发现了旁边的真 bug，却谁也没告诉
The agent sees a genuine problem near its task and neither fixes it nor reports it. Scope rules without a reporting channel make this worse.
Applies to: Claude Code · Cursor · Codex · Copilot agent
Symptom
Weeks later you hit a bug in a file the agent read during an earlier task, and the transcript shows it noticed.
Why it happens
Staying in scope is right, but silence loses the information. agent-failure-modes lists AFM-3 Swallowed Finding (Replicated). The dev.to diff-budget author hit the same side effect, where blocked observations "simply vanished", and fixed it with a parking-lot file.
Example
From the dev.to diff-budget post (parking lot entry).
markdown## Parking lot: task-0412
- src/search/cursor.py has the same off-by-one pattern as the pagination helper.
Likely the same bug. Suggested task: bug fix, tight budget.
Copy-paste fixes
Pick the files for the agents you use. Snippets are in English so they work in any repo.
Claude Code: add to CLAUDE.md
CLAUDE.md## Report what you notice, don't silently fix or ignore it
- If you notice a bug, security issue or risky code outside your task, don't fix it in this change,
and don't stay silent: add it to FOLLOWUPS.md and mention it in your final summary under "Noticed, not fixed".
- Include file, line, what's wrong, how sure you are, and a suggested task.
Codex, Copilot coding agent and others: add to AGENTS.md
AGENTS.md## Report what you notice, don't silently fix or ignore it
- If you notice a bug, security issue or risky code outside your task, don't fix it in this change,
and don't stay silent: add it to FOLLOWUPS.md and mention it in your final summary under "Noticed, not fixed".
- Include file, line, what's wrong, how sure you are, and a suggested task.
Cursor: project rule
.cursor/rules/swallowed-finding.mdc---
description: "AgentFails: Noticed the real bug next door and told no one"
alwaysApply: true
---
## Report what you notice, don't silently fix or ignore it
- If you notice a bug, security issue or risky code outside your task, don't fix it in this change,
and don't stay silent: add it to FOLLOWUPS.md and mention it in your final summary under "Noticed, not fixed".
- Include file, line, what's wrong, how sure you are, and a suggested task.
FOLLOWUPS.md parking lot
FOLLOWUPS.md## Noticed, not fixed
- <file:line>: <what is wrong>. Confidence: <high|medium|low>. Suggested task: <type, priority>.
Shared /verify skill for Claude Code
Commit it to the repo so the whole team (and every agent session) runs the same checks. Replace the commands with your project's real ones.
.claude/skills/verify/SKILL.md---
name: verify
description: Verify the current change before calling it done. Use before every commit, PR, or "done" message.
---
# Verify
Run every step and paste the real output. Never summarize a step you did not run.
1. **Scope**: run `git diff --stat` and `git status --short`. For every changed file, say which part
of the request needs it. Any file you cannot justify gets reverted, or listed under
"Unrequested changes" for the user to decide.
2. **Build and types**: `npm run build` (or the project's build command).
3. **Tests**: `npm test`. Report pass/fail counts. If a test was edited, skipped or deleted,
say so explicitly with the reason.
4. **Behavior**: exercise the changed behavior once for real (a curl, a CLI run, a screenshot)
and show what happened.
5. **Report** in this format:
- Requested: <one line>
- Changed files: <list, each with its reason>
- Checks run: <command -> result>
- Not done / unsure: <list, or "none">