Discovery Spec

Implement AgentCash discovery for this server and make it pass.

Discovery strategy:
Your api should expose an OpenAPI document at /openapi.json, which abides by the OpenAPI specification,
with several additional fields required for MppScan and AgentCash discovery.
You can use the @agentcash/discovery package to validate your OpenAPI document.

Validation commands:
npx -y @agentcash/discovery@latest discover "$TARGET_URL"
npx -y @agentcash/discovery@latest check "$TARGET_URL"


This will yield warnings regarding the discovery document and how it can be improved.

Schema guidance (important):
- Each invocable route should expose an input schema.
- In OpenAPI, define requestBody.content["application/json"].schema.
- This is required for reliable agent invocation and robust listing behavior.
- Add high-level guidance in info.x-guidance for agent-friendly discovery. This document should explain to an agent how to use your API at a high level.

OpenAPI payable operation must include ALL:
- x-payment-info with:
  - protocols: array of protocol objects, e.g. [{ "x402": {} }, { "mpp": { "method": "", "intent": "", "currency": "" } }]
  - price: object with mode + fields:
    - fixed: { "mode": "fixed", "amount": "<amount>", "currency": "<currency>" }
    - dynamic: { "mode": "dynamic", "min": "<min>", "max": "<max>", "currency": "<currency>" }
- responses: { "402": { description: "Payment Required" } }

Authed (identity-only) endpoints:
For endpoints that require identity but no payment, use zero-dollar auth by setting the price amount to "0" — the client signs the Challenge to prove key ownership without any funds transfer. See https://mpp.dev/advanced/identity for full details on identity verification, access control, and multi-step workflow patterns.

Minimal valid example:
{
  "openapi": "3.1.0",
  "info": {
    "title": "My API",
    "version": "1.0.0",
    "description": "example demo server",
    "x-guidance": "Use POST /api/search for neural web search. Accepts a JSON body with a 'query' field."
  },
  "x-discovery": {
    "ownershipProofs": ["<proof-1>"]
  },
  "paths": {
    "/api/search": {
      "post": {
        "operationId": "search",
        "summary": "Search - Neural search across the web",
        "tags": ["Search"],
        "x-payment-info": {
          "price": {
            "mode": "fixed",
            "currency": "USD",
            "amount": "0.010000"
          },
          "protocols": [
            {
              "x402": {}
            },
            {
              "mpp": {
                "method": "",
                "intent": "",
                "currency": ""
              }
            }
          ]
        },
        "requestBody": {
          "required": true,
          "content": {
            "application/json": {
              "schema": {
                "type": "object",
                "properties": {
                  "query": { "type": "string", "minLength": 1, "description": "The query string for the search" }
                },
                "required": ["query"]
              }
            }
          }
        },
        "responses": {
          "200": {
            "description": "Successful response",
            "content": {
              "application/json": {
                "schema": {
                  "type": "object",
                  "properties": {
                    "results": { "type": "array", "items": { "type": "object" } }
                  },
                  "required": ["results"]
                }
              }
            }
          },
          "402": { "description": "Payment Required" }
        }
      }
    }
  }
}


Workflow:
1) Validate your OpenAPI document with the @agentcash/discovery package.
2) Fix your OpenAPI document until it passes validation.
3) Register your server on MPPScan once it passes validation.