Numbers Online

Numbers Online A2A Agent

An Agent-to-Agent (A2A protocolVersion 0.3.0, JSONRPC) endpoint at POST https://numbers.online/api/v1/a2a exposing four read-only skills — phone_lookup, line_type, caller_risk and dnc_check — the same capabilities as the MCP tools. Discovered via the provider-served agent card at /.well-known/agent-card.json (also /.well-known/agent.json and /api/agent-card). Bearer API key with the mcp use case; anonymous message/send returns 401 missing_key and GET returns 405. This endpoint is not described in the OpenAPI.

GitHub

Documentation

📖
Documentation
https://numbers.online/docs

Other Resources

🔗
AgentCard
https://raw.githubusercontent.com/api-evangelist/numbers-online/refs/heads/main/a2a/numbers-online-a2a.yml
🔗
AgentCard
https://numbers.online/.well-known/agent-card.json
🔗
ToolCrosswalk
https://raw.githubusercontent.com/api-evangelist/numbers-online/refs/heads/main/mcp/numbers-online-tool-crosswalk.yml

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API entry from apis.yml

apis.yml Raw ↑ 
aid: numbers-online:numbers-online-a2a-agent
name: Numbers Online A2A Agent
description: An Agent-to-Agent (A2A protocolVersion 0.3.0, JSONRPC) endpoint at POST https://numbers.online/api/v1/a2a
  exposing four read-only skills — phone_lookup, line_type, caller_risk and dnc_check — the same capabilities
  as the MCP tools. Discovered via the provider-served agent card at /.well-known/agent-card.json (also
  /.well-known/agent.json and /api/agent-card). Bearer API key with the mcp use case; anonymous message/send
  returns 401 missing_key and GET returns 405. This endpoint is not described in the OpenAPI.
image: https://numbers.online/android-chrome-512x512.png
humanURL: https://numbers.online/docs
baseURL: https://numbers.online/api/v1/a2a
tags:
- A2A
- agent-native
- Phone Intelligence
properties:
- type: AgentCard
  url: a2a/numbers-online-a2a.yml
- type: AgentCard
  url: https://numbers.online/.well-known/agent-card.json
- type: Documentation
  url: https://numbers.online/docs
- type: ToolCrosswalk
  url: mcp/numbers-online-tool-crosswalk.yml