Getting Started

Authentication

All API requests must include your key in the X-API-Key header. Keys are issued per user and tied to a specific tier. See Tiers & Limits for what each one unlocks.

clg_core_*Core tier: 10,000 req/day, 1,000 rows/req, 542 fields, 4 hours sampling

clg_pro_*Pro tier: 50,000 req/day, 5,000 rows/req, 660 fields, 1 hour sampling

clg_alpha_*Alpha tier: Unlimited (fair use) req/day, 10,000 rows/req, 1,086 fields, 10 minutes sampling

Missing or invalid key → 401 Unauthorized

Example

HTTP header

X-API-Key: clg_pro_YOUR_KEY_HERE

Key prefixes

Keys carry the tier they were issued under: clg_core_, clg_pro_, clg_alpha_.

The prefix records what your plan was when the key was created, not what it is now. Entitlement is resolved from your account on every request, so if you change tier your existing key keeps working and immediately reflects the new plan, while its prefix still reads the old one. Ask us for a fresh key if the mismatch is confusing in your logs. The tier field in every response is the authoritative answer.