PubFi’s executable capability authority is the currently installed Registry v2 generation. The public catalog is:
It returns the paginated pubfi.gateway.registry.capability-page.v5 schema. Each compact summary identifies the capability, public provider key, exact route matcher, allowed methods, credential requirement, method-specific billing, and readiness. Follow each opaque next_cursor to enumerate the complete installed generation. Use Runtime OpenAPI for the ready operation request and response schemas. Each operations[] entry pairs one HTTP method with one billing state: Do not read credit_cost from the capability root. For a priced operation, read it from the operations[] entry that matches the selected method. A new price uses a new price_version.

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Free Variants

A capability can also expose an optional top-level free_rate_limit with these effective account-level limits:
  • requests_per_window and window_seconds define one fixed request window;
  • max_concurrency bounds simultaneous upstream attempts; and
  • permit_ttl_seconds recovers an in-flight permit after an interrupted request;
  • optional quota defines an independent longer fixed window;
  • optional total_request_limit defines a cumulative admitted-request cap; and
  • optional bucket_scope identifies whether eligible routes share one provider allowance.
When this object is present, append :free to the final path segment of the advertised exact GET or POST route. Use the same PubFi API key and billing-account identity. A free route can require a server-side provider credential and can have a request body; the current route schema remains authoritative for its input. The free lane charges no Credits. A route-specific policy can replace the API default; the two policies are not cumulative. This is separate from free_health, which uses its advertised exact path without a suffix or API key. The checked-in Subscan Free Plan policy uses 2 requests per second, 2 concurrent attempts, a 120-second permit TTL, and a provider-scoped quota of 20,000 requests per 86,400 seconds. Eligible exact Subscan routes share this allowance for one billing account. This applies to the default Polkadot routes and bounded {network} routes, including XCM, multi-chain, Pro, and /api/v2/scan/accounts/net_assets operations. A network value must be an exact alias in the installed source-declared origin set; it does not create an arbitrary upstream hostname. The policy does not prove that any route is installed or ready. Clients must require the current catalog free_rate_limit or matching OpenAPI x-pubfi-free-variant before they use the suffix.

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Current Readiness

Registry v2 exposes two execution readiness states: Terms such as requestable, contract_ready, and research_spike belong to Discovery editorial context. They do not make a Registry operation executable.

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OpenAPI

https://api.pubfi.ai/openapi.json is generated from the installed Registry snapshot. It includes only current ready gateway routes. PubFi does not publish separate static provider OpenAPI files as execution authority. OpenAPI query parameters and body schemas describe the source-declared contract for discovery, examples, and client construction. At execution time, PubFi preserves and forwards the caller’s query exactly. It does not reject duplicate or undeclared query fields or enforce declared query-value relationships. The query must still be a valid RFC 3986 query component and must not exceed 65,536 encoded bytes. A non-empty POST body is bounded by the selected route and forwarded byte-for-byte with the route-selected media type. The source schema does not admit those bytes online. Empty bodies are omitted, and GET bodies are rejected. Every generated gateway operation includes x-pubfi-billing. For quantro_priced, the same method price is also available as x-pubfi-credit-cost, x-pubfi-price-policy-key, x-pubfi-price-version, and x-pubfi-x402. The x402 object contains network, asset, atomic_amount, and offer_id. The four top-level price extensions are absent for free_health and pricing_unavailable. An operation with an effective free policy includes x-pubfi-free-variant. That extension carries suffix: ":free" and the effective rate_limit object.

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Operation Pricing Inventory

GET https://api.pubfi.ai/v1/operation-pricing-inventory projects every typed operation in the installed Registry snapshot into one public-safe quantro.operation-pricing-inventory.v2 document. It identifies canonical operation keys, route revisions and closures, request bounds, and whether each operation is free_health or merchant_priced. It contains no selected Credit or x402 price and is not route-execution authority. The response uses Cache-Control: no-store. The complete projection fails with 503 when the snapshot is unavailable or includes an unapproved provider, unsupported matcher, duplicate route coordinate, or invalid plan. It does not silently omit an operation.

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Execution Response

A successful Registry gateway request returns the exact bounded provider body for that operation. The response also identifies the PubFi request and Registry generation through response headers. PubFi preserves bounded 2xx, 4xx, and 5xx status/body pairs and does not use a success envelope.

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Execution Boundary

A catalog entry is necessary but not sufficient for execution. Request-time checks still enforce:
  • the exact path and HTTP method;
  • the platform query syntax and byte bounds, plus the route-selected body byte limit and media type;
  • provider and credential readiness;
  • response byte bounds and relayable status classes;
  • caller authentication and allocation for the API-key lane; or
  • route-specific payment eligibility and valid authorization for the x402 lane.
Clients must refresh the catalog or Runtime OpenAPI instead of caching a route from an older generation as permanent authority. Continue with Provider Readiness for gate evidence and Route Planning for exact path-and-method selection.