GET /api/cycle/feed/<hlf_token>[.ics] answers any calendar app with the
record's forecast as RFC 5545: all-day events for the next few periods
over their widening windows, optionally past periods, and for a
conception goal that asks for it the next fertile window. Dates and a
title only; discreet titles and the calendar name "HealthLog" by default.
The body is built live on every fetch in the record's own zone and
language, never the request's. ETag is the content hash and a matching
If-None-Match answers 304; DTSTAMP moves only when the content does.
The feed is anonymous, so every gate is read per fetch: the auth-surface
limit before any lookup, the token's shape, the HMAC lookup of a live
feed, a per-token bucket, then the record and carrier not pending
deletion, the operator's external-access switch, cycle tracking for the
record, and for a feed a delegate minted, a live MANAGE grant covering
cycle. Every miss is the same 404.
/api/cycle/feed-subscription (status, turn on, options, turn off) and
its rotate are cookie-only through requireRecordAuth("manage", "cycle"),
with a fresh proof on turning on and rotating and a per-actor mint
bucket. The URL is returned once; the status carries the prefix, the
options, the fetch statistics as a calendar-app family and the
projection state.
The hlf_ family is registered with the path and token redactors, the
secret-shape refusal, the proxy's public paths and edge headers, the
URL-credential, sharing, recent-proof, step-up and module-gate guards,
the error-code catalogue, the activity feed and the destructive-control
registry. The cycle settings tab gains the subscription card and the
predictions panel lists the later cycles.
HealthLog API Spec
openapi.yaml is the OpenAPI 3.1 description for the HealthLog
Next.js API and the source of truth for the native iOS client's DTO
codegen. The file is generated: pnpm openapi:generate emits it
from the Zod registry under src/lib/openapi/ (registry.ts plus the
route modules in src/lib/openapi/routes/). Do not edit the YAML by
hand; the next generation overwrites it, and CI (openapi:check)
fails the build when the committed YAML drifts from the registry.
The MCP server is documented separately — it is a distinct contract over JSON-RPC, not part of the REST OpenAPI spec:
mcp-capabilities.md— the tool, resource, and prompt catalogue, the grounding contract, and the write model.mcp-skills.md— building a connector or skill on top of it.../self-hosting/mcp.md— enabling and connecting the surface (operator guide).
Preview locally
Open an interactive Redoc preview in your browser:
npx @redocly/cli preview docs/api/openapi.yaml
Generate static HTML for sharing:
npx @redocly/cli build-docs docs/api/openapi.yaml --output docs/api/index.html
Validate
npx @redocly/cli lint docs/api/openapi.yaml
The spec is expected to be lint-clean (errors = 0). Warnings such as
no-server-example.com for the localhost dev server are tolerated;
re-run the lint to see what it produces against the current file
before treating a warning as a regression.
Layout
info— title, description, andversionmirrored automatically frompackage.jsonat generation time. Never bump it by hand.servers—https://healthlog.example.comas the self-hosted placeholder plushttp://localhost:3000for local development.tags— domain groupings; the current set lives at the top of the generated file (Auth,Measurements,Medications,Mood,Analytics,Insights,Consent,Dashboard,Notifications,Devices,Export,Sync,Cycle,MeasurementReminders,Labs,Illness,Documents,Records,Admin,Meta,Retired).securitySchemes:-
bearerAuth—hlk_*API tokens. A scope grants what it names and nothing adjacent, so where a token comes from decides what it reaches:- a completed password / passkey / refresh exchange mints the
cookie-equivalent
["*"]token the native client carries; - a medication's own API-endpoint toggle mints
medication:ingestplusmedication:<id>:ingest, the pair/api/ingest/medicationgates on; POST /api/mcp/tokensmintshealth:read(optionally plushealth:write), audience-bound to/mcpand refused on REST writes;POST /api/tokens/measurementsmintsmeasurements:write, accepted byPOST /api/measurementsandPOST /api/measurements/batchonly, on the holder's own record only. The readings it writes carrysource: EXTERNALand are linked to the token; whether the HealthLog app writes them into Apple Health is the token'smirrorToAppleHealthsetting (off by default, changed withPATCH /api/tokens/{id}), resolved onto every measurement row asappleHealthMirror;POST /api/tokens/workoutsmintsworkouts:write, accepted byPOST /api/workouts/batchonly, on the holder's own record only; the workouts it writes carrysource: EXTERNAL;POST /api/tokens/documentsmintsdocuments:write, accepted byPOST /api/documents/inboundandGET /api/documents/inbound/sourceonly.
POST /api/tokensis not among them — that generic mint was removed in v1.30.17. The path still lists (GET) and revokes (DELETE /api/tokens/{id}) every token above, whichever surface issued it. - a completed password / passkey / refresh exchange mints the
cookie-equivalent
-
sessionCookie— HttpOnly session cookie set by the password and passkey login flows. Used by the web app and any iOS client running inside a web view. It is named__Host-healthlog_sessionwherever it isSecure(every HTTPS install), so no other host under the same domain can set it; a plain-HTTP install keepshealthlog_session. A cookie under the old name is still read and is re-issued under the new one.
-
components.schemas— DTOs for the documented routes plus the underlying Prisma models (e.g.Measurement,Medication,MedicationIntakeEvent,MoodEntry,User,DashboardLayout,ApiEnvelope,ApiError).paths— the client-facing REST surface. Not everysrc/app/api/**/route.tsis in the contract: most/api/admin/*routes, the OAuth connect/callback legs, and the webhook surfaces are not documented here. TheRetiredtag lists removed paths that answer410 Gone.
Conventions
- Successful responses use the envelope
{ data, error: null }. - Error responses use the envelope
{ data: null, error: '<message>' }. - Pagination uses
limit+offsetquery parameters and ameta: { total, limit, offset }block on the response. - All timestamps are ISO 8601 / RFC 3339 (
format: date-time) in UTC. - IDs are CUIDs (opaque strings).
Updating the spec
When adding or changing routes:
- Update the relevant route handler under
src/app/api/**/route.ts. - Change the Zod schemas and their
.meta()registrations undersrc/lib/openapi/(registry entry plus the matching module insrc/lib/openapi/routes/). KeepoperationIdcamelCase and stable; the iOS codegen keys off it. - Run
pnpm openapi:generateand commit the regeneratedopenapi.yamlalongside the schema change. CI'sopenapi:checkfails on drift. - Never edit the YAML directly and never bump
info.versionby hand; the version followspackage.jsonat generation time.