Judge agent-written libraries with test suites your side did not write

What you end up with

When an agent writes both the code and the tests, passing tests prove little.

What you get

• A plain-language summary of the workflow
• A fill-in prompt template
• What to watch out for
• A link to the original source

Who it is for

Builders who already use AI agents and want a proven workflow they can copy into their own project.

Works with

Solid chips: the agent is named in this listing's own tools list. Dashed chip: Plain Markdown, so it also pastes into other agents such as Grok Bot, Hermes, OpenClaw or Muse. We list those as compatible by format only, not as tested.

Tools needed

Cost to run: Free with the agent plan you already use.
Time to result: One working session

How it works

1. Find the official or most widely used conformance suite for what you a

   Find the official or most widely used conformance suite for what you are building

   Expected: Done before you move to the next step.

2. Wire it in as the only definition of done

   Wire it in as the only definition of done

   Expected: Done before you move to the next step.

3. Let agents read failures, never edit the suite

   Let agents read failures, never edit the suite

   Expected: Done before you move to the next step.

4. Publish the pass rate and the failing cases

   Publish the pass rate and the failing cases

   Expected: Done before you move to the next step.

5. After each release, fix the process before starting the next build

   After each release, fix the process before starting the next build

   Expected: Done before you move to the next step.

Sample prompt from the pack

Apply this workflow to [your project]:
1. Find the official or most widely used conformance suite for what you are building
2. Wire it in as the only definition of done
3. Let agents read failures, never edit the suite
4. Publish the pass rate and the failing cases
5. After each release, fix the process before starting the next build
Stop and ask me before anything irreversible: deploys, payments, sends or deletes.

Free preview of the file

# Judge agent-written libraries with test suites your side did not write

PaperChase agent use case (free feed entry), version 1.0. Source: [u/ai-tacocat-ia on r/vibecoding; Kurtis Welch, Recursive AI](https://www.reddit.com/r/vibecoding/comments/1xgvsu1/ai_code_is_slop_has_a_problem_test262/), 2026-10-27.

## What they did

Recursive AI describes a factory that rewrites an existing kind of library from scratch in a target language, with no dependencies beyond the base library. Specialist agents plan, manage, build and review, following a process written into their shared prompts. Each library is judged by an outside test suite rather than tests the agents wrote: the post cites 99.55% on test262 for a JavaScript engine, 100% on html5lib for an HTML parser, 330 of 330 on a shader compiler suite and byte-identical output on the Opus audio test vectors. After each 1.0 release the owner adjusted the factory before the next run, and owner messages per library fell over time.

## Worth knowing

When an agent writes both the code and the tests, passing tests prove little. A suite written by someone else, ideally the standard's own, is a fair judge, and publishing the misses keeps the claim honest. All scores are the team's own; this is a vendor research write-up.

Worth knowing

• When an agent writes both the code and the tests, passing tests prove little. A suite written by someone else, ideally the standard's own, is a fair judge, and publishing the misses keeps the claim honest. All scores are the team's own; this is a vendor research write-up.
• Figures are as reported by the original author and were not re-measured by us.

Details

Version 1.0 · Updated Oct 27, 2026 · Markdown version of this page
License: Personal and commercial use. Credit the original source when you share the workflow. Download terms

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