MCP subregistry with liveness data

The official MCP Registry authenticates who published a server. It does not check whether the server still answers. FastDrop probes every endpoint it carries and republishes the result through the interface the official Registry defines.

What FastDrop's subregistry returns

The same server shape the official Registry defines, with one extra key under server._meta. A client that already parses the official registry response can read FastDrop's without changes and ignore the extra block if it does not need it.

{
  "servers": [
    {
      "server": {
        "name": "io.github.example/weather",
        "version": "1.2.0",
        "remotes": [
          { "type": "streamable-http", "url": "https://example.com/mcp" }
        ]
      },
      "_meta": {
        "io.modelcontextprotocol.registry/official": { "status": "active" },
        "dev.fastdrop/verification": {
          "last_probed": "2026-07-28T09:00:00.000Z",
          "answered": true,
          "keyed": false,
          "tools_count": 12,
          "consecutive_failures": 0,
          "package_only": false,
          "product_slug": "weather",
          "product_url": "https://fastdrop.dev/p/weather"
        }
      }
    }
  ],
  "metadata": { "count": 1, "nextCursor": null }
}

How the liveness block is structured

Every field under dev.fastdrop/verification comes from a probe, not from maker-supplied metadata.

Field	Type	Meaning
`last_probed`	string \| null	ISO timestamp of the last probe attempt
`answered`	boolean	True when the endpoint completed initialize + tools/list
`keyed`	boolean	True when the probe used a maker-supplied read-only credential
`tools_count`	number	Number of tools the endpoint returned
`consecutive_failures`	number	Misses in a row. At 15 the endpoint drops out of rotation
`package_only`	boolean	Package server (stdio) - no remote URL to probe
`product_slug`	string \| null	FastDrop listing slug, when one exists
`product_url`	string \| null	Canonical FastDrop listing URL

How often the data is refreshed

FastDrop syncs the official MCP Registry hourly and probes the endpoints it carries. A healthy endpoint is re-probed every 30 days. After 15 consecutive misses an endpoint drops out of the probe rotation until someone requests a manual re-check, so a URL that died two years ago stops costing a request every day.

The current state across everything checked is published on the verification report.

How to point a client at it

# list servers (cursor paginated)
curl "https://fastdrop.dev/v0.1/servers?limit=100"

# next page
curl "https://fastdrop.dev/v0.1/servers?limit=100&cursor=<nextCursor>"

# one server's versions
curl "https://fastdrop.dev/v0.1/servers/<url-encoded-name>/versions"

# health
curl "https://fastdrop.dev/v0.1/health"

Reads are unauthenticated. Server names are reverse-DNS and must be URL-encoded in path parameters.

How this relates to the official MCP Registry

The official registry verifies who published a server. It does not check whether the server still answers. We do. Its metadata is deliberately unopinionated and it invites downstream aggregators to add curation and additional metadata - the liveness block is exactly that.

FastDrop is not a replacement for the official MCP Registry. Publish there first; FastDrop picks it up and probes it. For how registries, aggregators and a launch fit together, see the discoverability guide.

Questions

How often is the liveness data refreshed?

FastDrop syncs the official MCP Registry hourly. A healthy endpoint is re-probed every 30 days. After 15 consecutive misses an endpoint drops out of the probe rotation until someone requests a manual re-check.

How does this relate to the official MCP Registry?

The official registry verifies who published a server. It does not check whether the server still answers. FastDrop does. The subregistry re-exports registry metadata in the shape the official Registry defines and adds a verification block under _meta.

Does the subregistry require authentication?

No. GET /v0.1/servers, the version endpoints, and /v0.1/health are unauthenticated reads.

What happens to servers the official registry will not carry?

The official registry excludes private servers by policy. FastDrop can probe an authentication-gated endpoint when the maker supplies a read-only credential, and marks the result keyed so callers know a credential of their own is required.