Agent-to-Agent (A2A) Payment Protocol Headers
Google's Agent-to-Agent (A2A) protocol lets agent frameworks discover how to pay each other automatically. SqueezeOS's MCP server adds two response headers to every HTTP 402/403 payment-verification response so A2A-compatible frameworks can resolve payment requirements without parsing a response body, plus a full AgentCard at /.well-known/agent.json.
Quick facts
- Protocol header:
X-A2A-Payment-Protocol: x402/1.0 - Destination header:
X-A2A-Receiving-Address: <XRPL address> - AgentCard:
https://squeezeos-api.onrender.com/.well-known/agent.json(live) and a static mirror athttps://www.scriptmasterlabs.com/.well-known/agent.json, schemaagent-card/v1. - Card contents: x402 payment config, ARGUS tier table, skills with pricing, quickstart commands, provider metadata.
Frequently asked questions
What does the X-A2A-Payment-Protocol header do?
It tells an A2A-compatible framework which payment scheme is in play (“x402/1.0”) purely from response headers, without needing to parse the JSON body.
Where do I send the payment?
The X-A2A-Receiving-Address header carries the destination XRPL address directly — no lookup required.
Is there a machine-readable summary of everything an agent needs?
Yes — the AgentCard at /.well-known/agent.json bundles payment config, pricing, and quickstart calls in one document, returned with Access-Control-Allow-Origin: *.