why

Use for 'why does X work this way', 'why does this kernel use this tile size', 'why does this dispatch threshold exist', 'why was this perf guard added', design rationale, regressions, or postmortems. Discovers available MCPs and queries each evidence category (code history, source control and PRs, issue tracker, long-form docs, chat) in parallel, with an incident lens for defensive code, then returns a cited read on decisions and tradeoffs. Use how for runtime behavior.