docs(loops): record the 2026-07-25 api-drift run against spec 1.37

[drakulavich]

Updates docs/loops/api-drift-watcher-state.md for this week's api-drift-watcher run — the first one that had a spec to diff against.

Result: no drift

cloud.ouraring.com is reachable again, so the egress blocker from the 2026-07-17 baseline is closed (noted in the file, kept one cycle before deletion).

Current spec is 1.37 (1.38+ 404s; the baseline guessed 1.35). Every field in the dependency table is present in 1.37 with no removals, renames, or type changes.

Full 1.35 → 1.37 diff: 0 paths added/removed, 0 schemas added/removed, 1 schema changed — ValidationError gained ctx and input (Pydantic v2 error shape). Response payloads untouched.

Three findings, filed separately

Diffing code against a real spec for the first time surfaced three fields declared string that the spec marks nullable — daily_stress.day_summary, workout.label, sleep.type. Not a break (nullable columns, and importDaily already wrote w.label ?? ''). Fixed in #23.

The field-hash column was broken

Worth calling out, since it is the file's whole drift signal.

The hashes recorded on 2026-07-17 (63c05075bfc2, c5b01cb3b7fe, …) cannot be reproduced by the recipe the file documents — sha256(sorted, comma-joined field paths). I tried the current code's field names sorted/declaration-order/with-types/with-spaces, and this file's own "Fields read" cells verbatim and re-tokenised. Nothing matches any row.

The field lists were correct — they still match src/api/types.ts exactly, field for field. Only the hashes were wrong, which means the column could never have flagged a change.

Repaired by:

• recomputing every hash,
• printing the hashed string verbatim in the Fields read cell (already sorted, comma-joined, no spaces), so the input is not left to prose interpretation,
• pinning the recipe to a copy-pasteable command.

Every row now self-verifies from the file alone:

$ printf '%s' 'bpm,source,timestamp' | shasum -a 256 | cut -c1-12
f612441464e4

I checked all 9 rows this way — hash matches and field list is sorted.

Also added for the next run

• The unread-but-available surface per endpoint (12 fields on daily_activity, 13 on sleep, plus heartrate.timestamp_unix and daily_cardiovascular_age.pulse_wave_velocity), so a future feature does not have to re-derive it.
• The spec URL pattern and the probe-upward-until-404 trick for finding the current version.
• That the vo2max endpoint is served as vO2_max (capital O), not daily_vo2_max — relevant whenever that dormant surface gets wired up.

Docs only; no CHANGELOG entry since nothing user-visible changes.

[greptile-apps]

Greptile Summary

Updates the API drift watcher state for the 2026-07-25 run.

• Records successful comparison against OpenAPI spec 1.37 with no consumed-surface drift.
• Documents three open nullability mismatches filed in fix(api): type day_summary, label and sleep type as nullable #23.
• Recomputes field hashes with reproducible inputs and adds reference information for future runs.

Confidence Score: 5/5

The PR appears safe to merge.

No blocking failure remains.

Important Files Changed

Filename	Overview
docs/loops/api-drift-watcher-state.md	Records the latest drift run and now accurately states that #23 remains open and the corresponding type declarations are unchanged.

_{Reviews (2): Last reviewed commit: "docs(loops): say the mismatches are file..." | Re-trigger Greptile}