Documents the ScarfMon perf instrumentation harness shipped in v2.7.
Covers:
- User capture recipe (Settings → Diagnostics → Performance, Reset, run scenario, Copy as JSON)
- Mode tradeoffs (off / signpostOnly default / full)
- Privacy stance: no remote upload, StaticString names, symbol-only stack frames
- Catalog of every measure point shipping today (chat render, chat stream, session load, sqlite, transport, disk I/O)
- Developer guide for adding new measure points
- Architecture diagram + ring-buffer sizing
- When to use Instruments instead
Linked from Home and Core-Services so it's discoverable.
Alan Wizemann