GET /api/topics answers one entry per topic the record holds data for:
a headline value, a rule-based sentence and a 30-day sparkline.
GET /api/topics/{topic} answers a topic's signals with their usual
ranges, side-by-side series for a chosen window, the relationships
between its signals, 90-day trends, what it holds nothing for yet, and
its blocks (training load, lab markers with their trend, screener
trends, the cycle day).
Every figure comes from reads the metric pages already make: the local
daily values, the reconstructed nights, the mood score, computeLabTrend,
the training load and the screener trends. No model is involved. A
relationship says nothing below 14 paired days and is only called a
pattern at p < 0.05; a lab trend needs three readings spanning a year.
The preview is the viewer's own opt-in: with it off both routes answer
404 topics.preview_off. Topics, signals and blocks follow the record's
module switches and the sections the viewer's grant opens; the routes
read across sections, so a scoped grant is refused like the timeline.
/api/auth/me publishes the caller's opt-ins as previewFeatures.
src/app/
The Next.js App Router tree: the page surfaces a logged-in user sees and the REST API under api/. Server components are the default; "use client" is added only where a hook, state, or browser API needs it. Routing is file-based — a page.tsx is a page, a route.ts is an API endpoint.
API routes (api/)
Every endpoint wraps its handler in apiHandler (@/lib/api-handler), parses any body with Zod safeParse, narrows userId from the session or Bearer token (never from the body), and returns the { data, error, meta? } envelope. requireAdmin() is cookie-only, so api/admin/ is unreachable by Bearer token. Notable groups:
auth/— login, register, password, passkey (WebAuthn), refresh, Codex device-OAuth.measurements/,mood-entries/,medications/,sleep/— the core health-data CRUD + batch/bulk ingest.ingest/— external Bearer-token ingest surfaces.insights/,analytics/,dashboard/— AI insights, the Coach SSE stream, trend summaries, the first-paint dashboard snapshot.withings/,whoop/,fitbit/,integrations/,sync/— OAuth connect/sync/webhook surfaces and the offline delta feed.fhir/,share-links/,doctor-report/,export/,import/— clinician-facing FHIR R4 read API, shareable records, report + data export.notifications/,devices/,send/,telegram/— channel registration, device tokens, dispatch, webhook intake.admin/— operator panel APIs (cookie-only).health/,version/,meta/,internal/— health check, build-version probe, runtime metadata, worker-internal routes.
Page surfaces
measurements/, medications/, mood/, insights/, achievements/, notifications/, settings/, onboarding/, admin/, plus the public about/, privacy/, bugreport/, the share-record route c/, and the root dashboard (page.tsx). Shared shell + chrome lives in layout.tsx; error.tsx / global-error.tsx / not-found.tsx / loading.tsx cover the framework boundaries. layout.tsx holds the one nonce-bound dangerouslySetInnerHTML (theme bootstrap).
Conventions
See ../../CLAUDE.md. The request-flow walk in .planning/codebase/arch.md annotates each layer with file:line citations. Related dirs: handlers compose ../lib/; pages render ../components/.