APIs.io has always been about making APIs findable — 8,900+ providers, 32,000+ APIs, and 119,000+ schemas you can search from a browser or hit through the REST API. But more and more of the traffic coming to the catalog isn’t a person typing a query — it’s an agent trying to ground itself in real API metadata before it acts. So we run an MCP server for exactly that, and as of last week it’s registered in the official MCP Registry.
One server, pointed straight at the catalog
The APIs.io MCP server lives at https://apis.io/mcp. It’s a remote, streamable-HTTP server — no install, no local process, no npm package to pull down. Point any MCP client at that URL and it gets read-only discovery over the whole APIs.io catalog:
apis_io_search— the one to start with. Full-text search across every provider, API, and artifact in the catalog.find_apis,find_providers,find_artifacts— list and filter the core records.find_tags,find_industries,find_regions,find_ratings— browse the catalog along the dimensions we organize it by.get_api,get_provider,get_tag,get_industry,get_region— pull the full detail record for anything the search or find calls surface.get_provider_rating,get_rating_rubric— read a provider’s quality score and the exact rubric behind it.
Every one of these is read-only. The server hands an agent structured, current facts about APIs — who publishes them, what artifacts they ship, how they rate — instead of leaving the model to guess from stale training data.
Why the registry matters
The official MCP Registry (registry.modelcontextprotocol.io) is the canonical, machine-readable index of MCP servers — the place a client, a directory, or an agent looks to answer “what MCP servers exist, and where do I connect to them?” Getting listed there means the APIs.io server is discoverable the same way we ask every provider in our own catalog to be discoverable: from one authoritative source, in a format a machine can resolve without a human in the loop.
We’re published under the name:
io.apis/apis-io
That name isn’t arbitrary. It’s a reverse-DNS namespace — io.apis/* is the domain-verified namespace for apis.io. To claim it we proved control of the domain with a TXT record on the apis.io apex, so no one else can publish a server under that namespace. The name is a verifiable claim, not just a label.
The published record itself is a small server.json describing the server — its name, description, version, website, source repository, and the remote endpoint. It’s versioned in the apis-io-aws repo alongside everything else that runs the platform, and bumping its version is how we ship an update to the listing.
Two discovery surfaces, both correct
If you’ve been following along, you know APIs.io also serves an SEP-2127 server card at its .well-known path. That’s a different surface from the registry listing, and both are intentional: the server card is the self-describing document you find at the server, and the registry entry is the catalog record you find before you get there. Same server, two ways to arrive at it.
Install it in a click
Because we carry a real registry name, installing the APIs.io server in your client is a one-liner. Drop the MCP Install button on any page and point it at the registry name — the chooser resolves the definition from the canonical source and renders the right install path for whatever client the visitor is running:
<script src="https://install.apicommons.org/button.js" async></script>
<mcp-install-button name="io.apis/apis-io"></mcp-install-button>
Or add it straight to a config-file client by hand — it’s just a remote URL:
https://apis.io/mcp
This is the same discipline we ask of every provider we index: publish your definition in one authoritative place, get it into the registries that matter, and let everything else reference it instead of copying it. We’ve now done that for our own MCP server. If you run one too, get it listed on APIs.io so agents can find it — and get it into the official registry so they can connect.
| The apis.io MCP server → | The official MCP Registry → | Add an install button → |