How we check

We copy the registry every 30 minutes and keep only the latest version of each server. We don't take listings from other directories. A few spam farms (thousands of near-identical entries from one publisher) are excluded by name; everything else in the registry is listed.

1. Connect to the server's remote URL over HTTPS with the transport the registry declares (streamable HTTP or the older SSE). If the server rejects that transport outright, we try the other one, as the MCP spec suggests for clients.
2. Send initialize and time the round trip. That is the latency we show.
3. Send tools/list and record the tools and their input schemas. A hash of the list tells us when it changes.
4. Close the session.

We never call a tool during a check. Each check has a 10 second limit, sends no credentials, and identifies itself with the user agent mcptry.com indexer. Checks run from a server in a single location, so latency is measured from there and will differ from yours.

We don't check URLs that can't work from the internet: localhost, private network addresses, raw IP addresses and temporary tunnels. URLs with placeholders (like your account name) can't be checked either, because we don't know your values.

Working

Our last check connected, initialized and listed its tools without credentials.

Needs sign-in

The server is up but asks for credentials before it will talk.

Paid per call

The server is up but asks for payment per request (HTTP 402).

Local install

Runs on your machine from a package. We don't run packages, so it isn't checked.

Not checked

Remote server we haven't checked yet, or one whose URL needs your own values filled in.

Down

Recent checks failed. It stays listed for 7 days of failures, then drops out of search.

Unreachable

Every check has failed for 7 days or more. It comes back as soon as a check passes.

A 401, 403 or 402 answer means the server is up and wants credentials or payment, so it counts as up, not as a failure. A server goes from down to unreachable after 7 days of failed checks and comes back the moment a check passes. Nobody has to claim a listing to keep it.

Every server gets a score out of 100 from things we can check ourselves. Each server page shows its own breakdown under “How it ranks”.

Results are ordered by score, with two adjustments. In a search, servers whose name or title matches come before servers that only mention the term in their description, and a brand's own server comes first. And no publisher gets more than 3 spots before everyone else has had a turn, so one catalog of hundreds of near-identical servers can't fill a page.

That is the whole formula. Nobody can pay to rank higher. If we list a tool we built ourselves, it follows the same rules and says so on its page.

Some pages show up to two servers above the results. A server labelled “Sponsored” is a paid placement. A server labelled “Featured” is our own unpaid pick, usually one of the top-scoring working servers in that category. Either kind must pass our health checks to appear: if it goes down, the placement pauses until it works again. Neither changes a server's score or its place in the ranking below.

To sponsor a category or a search, email [email protected].

Servers named after a domain (like com.example/server) were published by someone who proved control of that domain to the MCP Registry. We show that as “domain verified”. It confirms who published the entry, not that the server is good.

The playground connects to a server through mcptry, because browsers can't call most MCP servers directly. It only talks to remote servers and never runs packages. Headers you type in, such as API keys, are sent to that server for that one request and are never stored or logged. Tools that aren't marked read-only need an extra confirmation before they run.