Structured Reference Data.
Signed, sourced, and cheap to read.
Token-compressed component and developer-API reference data for agents. Every response is Ed25519-signed and verifiable against our published key, and every record cites its source. Pay per query from a prepaid metered key.
No card required. Accuracy is best-effort, not guaranteed — see terms.
Every key gets 50 free queries every day. No credit card required. Top up anytime with prepaid credit.
Choose your integration path:
Select an endpoint to inspect the real payload shape. Free endpoints return real data; paid endpoints demonstrate the live 402 challenge with token counts and pricing.
Executing query...
Prepaid credit, debited per successful query. Cached revalidations (HTTP 304) and rate-limited requests are never charged.
| Component specification lookup | $0.001 |
| API schema lookup | $0.002 |
| Natural-language catalogue search | $0.003 |
| Deprecation and sunset radar | $0.005 |
| Auth and error playbook | $0.005 |
| Cross-service capability search | $0.005 |
| Integration brief | $0.01 |
| Dependency upgrade advisory | $0.02 |
| Breaking-change and migration analysis | $0.02 |
| Free tier | 50/day |
Agents cannot enter card details. When credit runs low, an agent calls
factreason_create_topup_link and hands the link to a human — or you can turn on optional
automatic top-up.