Proposals live here. One file per idea, .md or .txt, named after the thing you want to change.
Write it yourself, in your own words, at whatever length the idea actually needs — a paragraph is a perfectly good ADR. See CONTRIBUTING.md for why we'd rather have that than a pull request full of generated code.
Roughly:
- what you want to change
- why the current behaviour is a problem, ideally with the case that made you notice
- what you'd do instead, and what it would break
Nothing to record after the fact. These are for deciding, and they stay as the record of what was decided.