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

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

Catalog › io.usefulapi/billy

Is Billy MCP by usefulapi reliable?

Reliable (measured) Yes. Faceabot measured Billy MCP by usefulapi 25 times: 100% of checks succeeded, including the last 25 in a row (last check 2026-10-19 08:05 UTC).

Last check: 2026-10-19 08:05 UTC · answered in 6591 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 Billy invoices, bills, contacts, products and postings; create contacts and draft invoices.

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

Connect your agent

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

Or ask Faceabot first: MCP tool check_reliability {"id":"io.usefulapi/billy"} 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 08:05 UTC	✅ ok	❌ auth_required	6591 ms
2026-10-18 15:25 UTC	✅ ok	❌ auth_required	5598 ms
2026-10-18 04:40 UTC	✅ ok	❌ auth_required	3945 ms
2026-10-17 20:40 UTC	✅ ok	❌ auth_required	6497 ms
2026-10-17 12:15 UTC	✅ ok	❌ auth_required	6859 ms
2026-10-17 04:35 UTC	✅ ok	❌ auth_required	9170 ms
2026-10-16 20:55 UTC	✅ ok	❌ auth_required	5050 ms
2026-10-16 13:46 UTC	✅ ok	❌ auth_required	5641 ms
2026-10-16 06:45 UTC	✅ ok	❌ auth_required	5497 ms
2026-10-15 23:50 UTC	✅ ok	❌ auth_required	4188 ms
2026-10-15 16:51 UTC	✅ ok	❌ auth_required	6589 ms
2026-10-15 10:11 UTC	✅ ok	❌ auth_required	4728 ms
2026-10-15 03:40 UTC	✅ ok	❌ auth_required	3252 ms
2026-10-14 21:15 UTC	✅ ok	❌ auth_required	4835 ms
2026-10-14 14:45 UTC	✅ ok	❌ auth_required	4151 ms
2026-10-14 08:20 UTC	✅ ok	❌ auth_required	2057 ms
2026-10-14 01:31 UTC	✅ ok	❌ auth_required	6009 ms
2026-10-13 19:20 UTC	✅ ok	❌ auth_required	9179 ms
2026-10-13 13:15 UTC	✅ ok	❌ auth_required	7441 ms
2026-10-13 07:11 UTC	✅ ok	❌ auth_required	6899 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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Read Accredible credentials, groups, designs, analytics, skills; issue one credential as a draft.

MCP endpoint : https://accredible.usefulapi.io/mcp · website · measurements and details

Publisher of Billy MCP by usefulapi?

Show your measured reliability on your README or website:

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

Data in JSON: /api/catalog?id=io.usefulapi/billy · 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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