FactReasonPay per query.
Prepaid credit, debited per successful query. Cached revalidations (HTTP 304) and rate-limited requests are never charged.
Free Trial Credit
Eligible new users receive up to $0.05 of one-off trial credit, subject to grant budgets and spent at the prices below — up to 50 component lookups, or 2 dependency upgrade advisories. No card required. Create a key at POST /api/v1/keys/create. Misses, rate-limited requests and cached revalidations are never charged and never consume trial credit.
Query Costs
Static reference data, cached indefinitely by the caller.
Versioned endpoint shape; changes on publisher release cadence.
Intent matching across the catalogue; returns ranked candidates.
Aggregates spec-declared deprecations, sunset dates, and replacement operations across services.
Aggregates declared auth schemes, scopes, rate-limit headers, and full error-code table per service.
Answers "which of these services can do X" across the whole index. Replaces an unbounded web search an agent cannot reliably perform.
Everything needed to write one working call — base URL, auth scheme, required parameters, body shape, response codes — compiled into a single response. Replaces five to ten schema lookups plus a documentation crawl.
What breaks between two published versions of a package, derived from publisher-declared registry metadata with the exact evidence field attached. Prevents a failed upgrade — same value class as an API breaking change, and unlike that tier the version ordering is declared rather than inferred.
Derived analysis that prevents a failed deployment. Recomputed as publishers ship.
Top-Up Blocks
Add prepaid credit via Stripe. Agents can generate checkout links via MCP.
Evaluation and small projects
Recommended — lowest effective fee per query
High-volume agent fleets