{
  "$schema": "http://json-schema.org/draft-07/schema#",
  "$id": "https://paxiom.org/standards/receipts/v0/paxiom.receipt.v0.schema.json",
  "title": "Paxiom Receipt v0",
  "description": "Developer-preview (v0 draft) schema for a proof-bound receipt for x402-paid APIs. x402 proves a payment; a Paxiom receipt binds payment, request, output, settlement metadata, and optional evidence into a single signed, machine-verifiable object. This schema validates STRUCTURE only; it does not assert that a receipt was settled onchain or that any proof is valid. Those are the verifier's job and are reported as trust states.",
  "type": "object",
  "additionalProperties": false,
  "required": ["receiptVersion", "payload", "signature"],
  "properties": {
    "receiptVersion": {
      "type": "string",
      "const": "paxiom.receipt.v0"
    },
    "payload": {
      "type": "object",
      "additionalProperties": false,
      "required": ["receiptId", "issuedAt", "issuer", "service", "request", "payment", "delivery", "evidence"],
      "properties": {
        "receiptId": { "type": "string", "minLength": 1 },
        "issuedAt": { "type": "string", "format": "date-time" },
        "expiresAt": { "type": "string", "format": "date-time" },
        "issuer": {
          "type": "object",
          "additionalProperties": false,
          "required": ["name", "keyId"],
          "properties": {
            "name": { "type": "string", "minLength": 1 },
            "uri": { "type": "string" },
            "keyId": { "type": "string", "minLength": 1 }
          }
        },
        "service": {
          "type": "object",
          "additionalProperties": false,
          "required": ["name", "resource", "method"],
          "properties": {
            "name": { "type": "string", "minLength": 1 },
            "resource": { "type": "string", "minLength": 1 },
            "method": { "type": "string", "minLength": 1 }
          }
        },
        "request": {
          "type": "object",
          "additionalProperties": false,
          "required": ["requestHash", "resourceHash", "bodyHash"],
          "properties": {
            "requestHash": { "$ref": "#/$defs/sha256Hex" },
            "resourceHash": { "$ref": "#/$defs/sha256Hex" },
            "bodyHash": { "$ref": "#/$defs/sha256Hex" }
          }
        },
        "payment": {
          "type": "object",
          "additionalProperties": false,
          "required": ["scheme", "network", "asset", "amountAtomic", "amountDisplay", "paymentRequirementsHash", "paymentPayloadHash", "settlement"],
          "properties": {
            "scheme": { "type": "string", "minLength": 1 },
            "network": { "type": "string", "minLength": 1 },
            "asset": { "type": "string", "minLength": 1 },
            "amountAtomic": { "type": "string", "pattern": "^[0-9]+$" },
            "amountDisplay": { "type": "string", "minLength": 1 },
            "paymentRequirementsHash": { "$ref": "#/$defs/sha256Hex" },
            "paymentPayloadHash": { "$ref": "#/$defs/sha256Hex" },
            "settlement": {
              "type": "object",
              "additionalProperties": false,
              "required": ["status", "transactionHash", "checkedByPaxiom"],
              "properties": {
                "status": {
                  "type": "string",
                  "enum": ["not_required", "disabled", "verify_only", "claimed_not_checked", "verified_settled", "failed", "unknown"]
                },
                "transactionHash": {
                  "oneOf": [{ "$ref": "#/$defs/sha256Hex" }, { "type": "null" }]
                },
                "checkedByPaxiom": { "type": "boolean" }
              }
            }
          }
        },
        "delivery": {
          "type": "object",
          "additionalProperties": false,
          "required": ["outputHash", "mimeType"],
          "properties": {
            "outputHash": { "$ref": "#/$defs/sha256Hex" },
            "mimeType": { "type": "string", "minLength": 1 }
          }
        },
        "evidence": {
          "type": "array",
          "items": {
            "type": "object",
            "additionalProperties": false,
            "required": ["type", "status", "hash", "uri"],
            "properties": {
              "type": { "type": "string", "enum": ["none", "zk", "attestation", "tee", "archive", "other"] },
              "status": { "type": "string", "enum": ["not_provided", "provided", "unavailable", "invalid", "verified"] },
              "hash": { "oneOf": [{ "$ref": "#/$defs/sha256Hex" }, { "type": "null" }] },
              "uri": { "oneOf": [{ "type": "string" }, { "type": "null" }] }
            }
          }
        }
      }
    },
    "signature": {
      "type": "object",
      "additionalProperties": false,
      "required": ["algorithm", "keyId", "publicKey", "value"],
      "properties": {
        "algorithm": { "type": "string", "const": "ed25519" },
        "keyId": { "type": "string", "minLength": 1 },
        "publicKey": { "type": "string", "minLength": 1 },
        "value": { "type": "string", "minLength": 1 }
      }
    }
  },
  "$defs": {
    "sha256Hex": {
      "type": "string",
      "pattern": "^0x[0-9a-f]{64}$",
      "description": "SHA-256 digest, lowercase hex, 0x-prefixed."
    }
  }
}