Overview

The APIs.io API is a discovery API over the APIs.io catalog — thousands of API providers and their published APIs, plus tags, industries, regions, ratings, and machine-readable artifacts (OpenAPI, AsyncAPI, Postman, Arazzo, JSON Schema, JSON-LD, GraphQL, rules, and more).

The same OpenAPI contract powers three surfaces:

• REST API — https://apis.io/api/v1 (API Reference)
• MCP server — https://apis.io/mcp for AI agents (MCP Server)
• Agent skills — apis.io/skills

Base URL

Code
https://apis.io/api/v1

Most endpoints are GET. The catalog itself — search, providers, APIs, tags, the place and topic taxonomies, the artifact collections, and everything about one provider — is open to a keyless caller on the Explore plan. Ranked, cross-catalog and own-your-listing resources need a plan — see Authentication and Plans.

Nothing published in the catalog is mutated by an API call. The 17 POST/DELETE operations write only to your own workspace (saved searches, lists, watches) or open a request that a person works — claim, dispute, correct, re-check, submit — and those answer 202 (a re-check request, POST /checks, answers 201 with the queued check).

Core resources

The plan column is the lowest plan that returns the resource; every operation in the reference carries the same thing as x-tier, using the wire names (free, pro, business) rather than the plan names.

Identifiers: providers are slugs (twilio); APIs are provider:api-slug (twilio:twilio-accounts-api).

Start with Getting Started for runnable examples, or jump to the API Reference.