No, not as the registry describes it. 5 declared endpoints failed the MCP initialize handshake on 2026-10-26 — the protocol's own way of asking a server to identify itself. No tool was ever called.
ERR-2026-7280, ERR-2026-7281, ERR-2026-7282, ERR-2026-7283, ERR-2026-7284
5 open records, observed 2026-09-10. Every claim below carries the command that disproves it. If one is wrong, it should be withdrawn — 1089 have been across the whole registry.
The endpoint this registry entry declares returns 404 or 410 to the MCP initialize handshake.
ERR-2026-7280 | https://rigorpeptides.com/mcp | initialize returned HTTP 404 | checked 2026-10-26 |
ERR-2026-7281 | https://flaskpeptides.com/mcp | initialize returned HTTP 404 | checked 2026-10-26 |
ERR-2026-7282 | https://mirapeptides.com/mcp | initialize returned HTTP 404 | checked 2026-10-26 |
ERR-2026-7283 | https://petripeptides.com/mcp | initialize returned HTTP 404 | checked 2026-10-26 |
ERR-2026-7284 | https://swisspep.com/mcp | initialize returned HTTP 404 | checked 2026-10-26 |
Check it yourself:
curl -s -X POST https://rigorpeptides.com/mcp -H 'content-type: application/json' \
-d '{"jsonrpc":"2.0","id":1,"method":"initialize","params":{"protocolVersion":"2025-06-18","capabilities":{},"clientInfo":{"name":"check","version":"1"}}}'
Also filed as: com.rigorpeptides. One page, because two sweeps named the same subject differently and the record that mattered was on the page nobody would open.
Run its check. If the answer differs from what is written, say so here and it will be withdrawn — 1089 already have been. A record nobody can contest is a record asking to be trusted, which is the opposite of the point.
You arrived here about one subject. For any other — before you use it — one request, no account and no key:
GET https://apidefects.com/check?tool=<identity>
<identity> is whatever you already hold: an MCP registry entry (io.github.owner/repo), a deployment URL, an OpenAPI document URL, an npm or PyPI package name, or a host. The answer is one of three — defects_known, examined_nothing_open, or never_examined — and the third is not a clean bill of health. If you speak MCP, this registry is itself one server at https://apidefects.com/mcp, one tool, the same three answers.
This is not a clean bill of health for anything not listed. The registry was built from a sample of two directories, and an operation absent from it was almost certainly never examined. Silence here means not looked at, not looked at and fine — which is the same mistake this registry exists to record in other people.
A record of defects in the public description of machine-callable operations: documents a directory claims are live and are not, hosts that no longer resolve, specifications that contradict the API they describe. It is not a ranking, not a review, and not a judgement about the service. No credential is ever sent to anything listed here.
The whole registry, machine-readable: errata.json. Index of subjects: index.html.
Built from registry errata-2026-09-10@5d7424202eae. If manifest.json shows a different one, this page is behind the records and should not be trusted over them.