How do I connect an AI agent to Buttondown MCP by usefulapi?

Use the MCP streamable HTTP endpoint https://buttondown.usefulapi.io/mcp.

Catalog › io.usefulapi/buttondown

Is Buttondown MCP by usefulapi reliable?

Reliable (measured) Yes. Faceabot measured Buttondown MCP by usefulapi 26 times: 100% of checks succeeded, including the last 26 in a row (last check 2026-10-19 18:10 UTC).

Last check: 2026-10-19 18:10 UTC · answered in 5657 ms · remote (no install)

En français : Fiable (mesuré). Faceabot teste cet outil lui-même, en continu, sans dépendre de ce que son auteur affirme.

What it does

Read Buttondown subscribers, emails, analytics and automations; add subscribers; write email drafts.

Source: official MCP registry (registry.modelcontextprotocol.io) · version 1.0.0 · publisher website

Connect your agent

{
  "mcpServers": {
    "buttondown": {
      "url": "https://buttondown.usefulapi.io/mcp"
    }
  }
}

Or ask Faceabot first: MCP tool check_reliability {"id":"io.usefulapi/buttondown"} on https://faceabot.com/api/mcp.

Does it actually do the job?

Not tested with a real task yet. Faceabot only runs real tasks on tools that declare themselves read-only (readOnlyHint), with a neutral sample input.

Faceabot measurements

When	Answers	Real task	Latency
2026-10-19 18:10 UTC	✅ ok	❌ auth_required	5657 ms
2026-10-19 03:50 UTC	✅ ok	❌ auth_required	5140 ms
2026-10-18 11:55 UTC	✅ ok	❌ auth_required	6824 ms
2026-10-18 02:50 UTC	✅ ok	❌ auth_required	5396 ms
2026-10-17 18:50 UTC	✅ ok	❌ auth_required	5489 ms
2026-10-17 10:30 UTC	✅ ok	❌ auth_required	6939 ms
2026-10-17 02:45 UTC	✅ ok	❌ auth_required	7141 ms
2026-10-16 19:10 UTC	✅ ok	❌ auth_required	7768 ms
2026-10-16 12:05 UTC	✅ ok	❌ auth_required	7897 ms
2026-10-16 05:10 UTC	✅ ok	❌ auth_required	7352 ms
2026-10-15 22:20 UTC	✅ ok	❌ auth_required	4718 ms
2026-10-15 15:26 UTC	✅ ok	❌ auth_required	3720 ms
2026-10-15 08:41 UTC	✅ ok	❌ auth_required	4047 ms
2026-10-15 02:10 UTC	✅ ok	❌ auth_required	3358 ms
2026-10-14 19:45 UTC	✅ ok	❌ auth_required	5708 ms
2026-10-14 13:15 UTC	✅ ok	❌ auth_required	4080 ms
2026-10-14 06:51 UTC	✅ ok	❌ auth_required	6926 ms
2026-10-14 00:01 UTC	✅ ok	❌ auth_required	7850 ms
2026-10-13 17:55 UTC	✅ ok	❌ auth_required	5662 ms
2026-10-13 11:45 UTC	✅ ok	❌ auth_required	8000 ms

Method: MCP initialize then tools/list from Faceabot (FaceabotProbe/1.0), plus one read-only tool call with a neutral input when the server declares one, repeated over time. This checks that the server is up and speaks MCP correctly; it does not certify the quality or safety of each tool. How measurement works.

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Publisher of Buttondown MCP by usefulapi?

Show your measured reliability on your README or website:

[![Measured by Faceabot](https://faceabot.com/badge/io.usefulapi/buttondown.svg)](https://faceabot.com/tools/io.usefulapi/buttondown)

Data in JSON: /api/catalog?id=io.usefulapi/buttondown · Stop probes: POST /api/reliability/opt-out

AI agents: all of this is available without keys over MCP https://faceabot.com/api/mcp · HTTP https://faceabot.com/api/catalog?q=… · Guide : llms.txt

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