write-code-eval
Write code evaluators for known failure modes with objective rules. Use when code can check the rule from a trace, with or without a reference answer. Use write-judge-prompt when the rule requires interpretation.
- Installs
- 363
- Last 24h
- +10
- Trending rank
- #8662
- Security
- Not audited
Install
Works with every agent the skills CLI supports.
npx skills add https://github.com/ai-evals-course/evals-skills --skill write-code-eval- 01
Install
Run the command in your project. The CLI asks which agents to install for.
- 02
Describe the task
Ask your agent for something this skill covers. It loads write-code-eval automatically when relevant.
- 03
Review the result
The agent follows the SKILL.md steps, scripts and references bundled with the skill.
SKILL.md
The instructions your agent reads when the skill is triggered.
Write a code evaluator
Start with a failure mode found through error analysis. Write one check for that failure mode, much like a unit test that asserts what should hold for each trace.
- State the rule and identify the trace fields or reference data the check needs. If the rule requires interpretation, use
write-judge-prompt. - Implement the check in the project's language and eval framework. Return a result and a reason in the format that framework expects.
- Test known passes and failures, including borderline cases. Run the check on available traces and inspect mistakes. If the rule uses a proxy for human judgment, compare its results with human labels.
Examples
| Failure mode | Possible check |
|---|---|
| Invalid output structure | Parse the output and check required fields |
| Missing or forbidden text | Match a string or pattern |
| Citation not in retrieved documents | Compare cited IDs with retrieved IDs |
| Bad tool call | Check arguments against the tool schema or run the call in a safe test environment |
| Wrong value | Compare the output with a reference value |
Choose the check from the failure rule. For a failure with both objective and interpretive parts, check the objective part with code and use a judge for the rest.
FAQ
What does the write-code-eval skill do?
Write code evaluators for known failure modes with objective rules. Use when code can check the rule from a trace, with or without a reference answer. Use write-judge-prompt when the rule requires interpretation.
How do I install write-code-eval?
Run npx skills add https://github.com/ai-evals-course/evals-skills --skill write-code-eval in your project. The skills CLI detects the agents you use and copies the skill into the right folder. For Claude Code you can also place the skill folder at ~/.claude/skills/write-code-eval/ (personal) or .claude/skills/write-code-eval/ (project).
Which AI agents can use write-code-eval?
Any agent that supports the open Agent Skills format (a folder with a SKILL.md file), including Claude Code, Codex, Cursor, GitHub Copilot, Gemini CLI, Windsurf, Cline, OpenCode and more.
Is write-code-eval safe to install?
No partner security audit is available yet. Skills can run commands and scripts, so read the SKILL.md and any bundled files before installing.
Who maintains write-code-eval?
It is published by ai-evals-course in ai-evals-course/evals-skills. It has 363 recorded installs.
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