Space Frontiers

Machine Library A2A Agent

A2A (protocolVersion 0.3.0) research and commerce agent at https://machinelibrary.ai/a2a over JSON-RPC: grounded research answers with citation artifacts, search-access guidance, and prepaid-credit sales settled through Stripe (ACP checkout sessions and MPP payment challenges), with two AP2 merchant-role extensions declared. The agent card is served at /.well-known/agent-card.json on machinelibrary.ai and spacefrontiers.org. Unauthenticated message/send is answered live with authentication guidance.

GitHub

Documentation

📖
Documentation
https://api.machinelibrary.ai/auth.md

Other Resources

🔗
AgentCard
https://raw.githubusercontent.com/api-evangelist/machinelibrary-ai/refs/heads/main/a2a/machinelibrary-ai-a2a.yml

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API entry from apis.yml

apis.yml Raw ↑ 
name: Machine Library A2A Agent
description: 'A2A (protocolVersion 0.3.0) research and commerce agent at https://machinelibrary.ai/a2a
  over JSON-RPC: grounded research answers with citation artifacts, search-access guidance, and prepaid-credit
  sales settled through Stripe (ACP checkout sessions and MPP payment challenges), with two AP2 merchant-role
  extensions declared. The agent card is served at /.well-known/agent-card.json on machinelibrary.ai and
  spacefrontiers.org. Unauthenticated message/send is answered live with authentication guidance.'
humanURL: https://machinelibrary.ai/.well-known/agent-card.json
baseURL: https://machinelibrary.ai/a2a
x-baseurl-note: JSON-RPC endpoint; answers POST message/send (200) and 404s a plain GET, so the humanURL
  is the served agent card rather than the endpoint.
tags:
- A2A
- Agent-Native
- Research
- Payments
tags_raw:
- a2a
- agent-native
- research
- payments
properties:
- type: AgentCard
  url: a2a/machinelibrary-ai-a2a.yml
- type: Documentation
  url: https://api.machinelibrary.ai/auth.md