Three documents that keep my AI coding agent honest (free templates + Claude Code skill)

I run a one-person R&D operation that ships industrial sensing products — analogue boards, microcontroller firmware, PC tools. Most of the typing is done by AI coding agents (mainly Claude Code). They are fast, and for a year they failed in the same four ways:

None of this was fixed by a better model. It was fixed by a process the agent cannot skip. I've generalized it into a small kit and put it on GitHub under MIT: ai-rd-process-kit.

Before any implementation, the agent writes three documents, and I accept them:

Then the agent works in small checked pieces, updates the documents in the same change that alters the design, and when it fails, it writes the lesson itself: situation, cause, prevention. It reads that file at the start of every session.

Unverified work stays at 75. Where things can be counted, they are counted: tests passed 38/52 → 73%.

"Not found" is not "does not exist." The agent searched a rulebook for two keywords, found nothing, and reported that no rule applied. The rule existed under different wording. Prevention: questions of the form "is there a rule about X" are answered by reading the relevant chapters, and the report says what was searched and what was not read.

ERC passed, the netlist had three shorts. An auto-generated schematic passed the electrical rules check. The netlist showed a rotated protection diode shorting two supply rails, a pull-up routed onto a data line, and a duplicated reference designator. Prevention: after generating a schematic, export the netlist and script-check supply/ground separation, polarity of oriented parts and duplicate designators before layout.

Five-minute setup: copy the templates into docs/, put the rules in CLAUDE.md, install the skill, and say "plan this". If the agent starts coding before showing you the scope table, the rules aren't loaded.

Not a methodology, not a tool, not a prompt pack. Four Markdown files and a habit. It works with any agent that reads an instruction file; the skill is for Claude Code.

If you try it, I'd like to know which rule your agent broke first. Mine was #4.

Disclosure: this post and the templates were drafted with an AI assistant and rewritten by me from first-hand use.