WorkedCoding
Keep an AGENTS.md 'harness' that encodes every recurring agent mistake
Tools: Coding agents (Claude Code, etc.), AGENTS.md
Setup, access, approval gate, failure notes
- Setup / prompt
- Each time an agent repeats a bad behavior, add an explicit rule or script to AGENTS.md (e.g. use the screenshot script, use test filters).
- Access required
- Repo working tree
- HITL checkpoint
- Developer reviews output and maintains the rules
- Outcome & failure notes
- Adoption came in stages, starting with skepticism. The value came from treating agent errors as harness bugs to fix permanently, not one-off prompt tweaks.
- Evidence type
- Developer first-hand
Source: Mitchell Hashimoto (blog) · 2026-02 · Checked 2026-10-19