send21.io
Raw data · 2 server URLs from the Official MCP Registry · simple view
Login-free handshake (initialize → tools/list; unpaid tools/call only on priced tools, to read the payment request; never paid, no credentials): automatic unauthenticated MCP handshake (initialize + tools/list), aiming for about once a day per listed server while we are still working through the registry; priority tier (host looked up via BotsRated preflight/check/report, or also a covered x402 seller, in the last 7 days) about every 6 hours; servers with no MCP answer for 7 days about every 4 days. States are factual: ok (initialize and tools/list answered), auth_required (HTTP 401/403: the server wants a login), handshake_failed (HTTP answer without a valid MCP result), unreachable (no HTTP answer), blocked (not contacted: the URL, a redirect or its DNS points to a private, local or otherwise non-public address, or to another host, which our rules don't allow). Names and descriptions are the registry's text; we don't check it.
| URL | Transport | Registry Name | Last State | HTTP | Protocol | Tools | Recent Checks OK | Median ms | TLS | Last Checked |
|---|---|---|---|---|---|---|---|---|---|---|
https://send21.io/mcp | streamable-http | io.github.send21io/mcp | ok | 200 | 2025-06-18 | 14 | – | 203 | ok | 22 h ago |
https://send21.io/mcp/oauth | streamable-http | io.github.send21io/mcp | auth_required | 401 | – | 177 | ok | 24 h ago |
MCP Check Receipts (Newest First, Up To 10 Per Server)
| Receipt | UTC Time | Path | State | HTTP | ms | Tools | Tools sha256 | Signed |
|---|---|---|---|---|---|---|---|---|
| 531bb57222973f94b29c | 2026-10-27T13:27:50Z | /mcp | ok | 200 | 93 | 14 | 8ff641b83a4d | per-receipt |
| 9c67d1a29f37ecf9a0a8 | 2026-10-27T11:51:46Z | /mcp/oauth | auth_required | 401 | 177 | per-receipt | ||
| e580e238b972ce169955 | 2026-10-26T13:27:49Z | /mcp | ok | 200 | 548 | 14 | 8ff641b83a4d | per-receipt |
| b2c9945df252d26a8c47 | 2026-10-26T11:51:44Z | /mcp/oauth | auth_required | 401 | 208 | per-receipt | ||
| b69f3aa111995faedcae | 2026-10-25T13:27:42Z | /mcp | ok | 200 | 190 | 14 | 8ff641b83a4d | per-receipt |
| 31ebb3040cbe0fb7f901 | 2026-10-25T11:51:45Z | /mcp/oauth | auth_required | 401 | 81 | per-receipt | ||
| 3303d5005df786d25833 | 2026-10-24T13:27:47Z | /mcp | ok | 200 | 203 | 14 | 8ff641b83a4d | per-receipt |
| fa9c713cc63ff2fb87bc | 2026-10-24T11:51:46Z | /mcp/oauth | auth_required | 401 | 75 | per-receipt |
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