# Open Sit — changelog

## 1.0 (2026-09-10) — initial

- Document envelope: `opensit`, `exported_at`, `generator`, `sessions`, optional `$schema` and `extra`.
- Session: `id`, `started_at` (with offset), `timezone?`, `duration_seconds` (total), `segments?`, `title?`, `note?`, `method?`, `mood?` (`label`, `intensity`, derived `valence`/`arousal`), `health?`, `source` (`name`, `id?`, `via?`), `extra?`.
- Normative duplicate detection (id → source pair → minute + total duration) and read validation.
- Compatibility projections documented for Timefully CSV, Insight Timer export, Apple Health / Health Connect.
- Fixtures: valid, invalid (with manifest), Insight Timer and Timefully CSV with expected outputs, 5,000-row performance file.
- License: CC0 1.0.