API · x402

Pre-flight a Base payment destination before you send

by payee.schemasure.com · discovered, not yet claimed by its owner · updated 2026-10-11

Mirrored from Coinbase's public x402 Bazaar. The description is the provider's own text and has not been reviewed here; the payment requirements are copied as published.

What it does

Pre-flight a Base payment destination before you send. Verifies the EIP-55 checksum, measures distance from an address you expect — catching a mistyped digit and the shared prefix-and-suffix shape of a ground look-alike — flags the zero address, burn sinks and precompiles, refuses a token offered as its own payee, and reports whether the destination can receive the asset. Returns unknown rather than guessing when bytecode does not decide it. Not a judgement of the counterparty.

Tags: base · payments · address · checksum · eip55 · bazaar

Use with an agent

Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
Inspect. Fetch /resources/36258.json for the price and payment options.
Pay. Call GET https://payee.schemasure.com/v1/guard/payee. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
Execute. The provider returns 200 with the data. Agent Bazaar is not in the request path and never sees your payment.

For humans

You don't need an account or an API key; you need a wallet holding a small amount of USDC on Base, and an x402-capable client (see the examples below). Call the endpoint unpaid first to see exactly what it asks for.

Pricing & payment

Price: $0.02 / request
Protocol: x402 v2
Auth: No account or API key. Pay per request.
Networks: Base
Calls (30d): 28 · 3 unique payers (third-party data from the public x402 Bazaar)

x402 payment requirements

Scheme	Network	Asset	Amount	Pay to	Timeout
exact	Base eip155:8453	USDC	$0.02	0x9876af0F6D8Ed5155Cd02d1ca56D128601612690	60s

accepts[] (raw JSON)

[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x9876af0F6D8Ed5155Cd02d1ca56D128601612690",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "20000",
    "amountUsd": 0.02,
    "maxTimeoutSeconds": 60
  }
]

Schemas

Output schema (JSON Schema)

{
  "properties": {
    "example": {
      "$schema": "https://json-schema.org/draft/2020-12/schema",
      "properties": {
        "data_versions": {
          "type": "object"
        },
        "evidence": {
          "items": {
            "type": "object"
          },
          "type": "array"
        },
        "ok": {
          "type": "boolean"
        },
        "policy_version": {
          "type": "string"
        },
        "request_hash": {
          "type": "string"
        },
        "result": {
          "properties": {
            "address": {
              "type": "object"
            },
            "asset": {
              "type": "object"
            },
            "can_receive": {
              "description": "value is true, false, or null when the bytecode does not decide it.",
              "type": "object"
            },
            "checksum": {
              "type": "object"
            },
            "denylist_hits": {
              "items": {
                "type": "object"
              },
              "type": "array"
            },
            "destination": {
              "type": "object"
            },
            "expected_comparison": {
              "type": [
                "object",
                "null"
              ]
            },
            "self_send": {
              "type": "object"
            },
            "sinks": {
              "type": "object"
            },
            "unresolved": {
              "items": {
                "type": "string"
              },
              "type": "array"
            }
          },
          "type": "object"
        },
        "risk_codes": {
          "items": {
            "type": "string"
          },
          "type": "array"
        },
        "verdict": {
          "description": "Precedence: block, then unknown, then warn, then allow.",
          "enum": [
            "allow",
            "warn",
            "block",
            "unknown"
          ],
          "type": "string"
        },
        "warnings": {
          "items": {
            "type": "string"
          },
          "type": "array"
        }
      },
      "required": [
        "ok",
        "verdict",
        "result",
        "request_hash",
        "data_versions"
      ],
      "type": "object"
    },
    "type": {
      "type": "string"
    }
  },
  "required": [
    "type"
  ],
  "type": "object"
}

Example shape — generated from the schema, not a captured live response

{
  "example": {
    "data_versions": {},
    "evidence": [
      {}
    ],
    "ok": true,
    "policy_version": "string",
    "request_hash": "string",
    "result": {
      "address": {},
      "asset": {},
      "can_receive": {},
      "checksum": {},
      "denylist_hits": [
        {}
      ],
      "destination": {},
      "expected_comparison": {},
      "self_send": {},
      "sinks": {},
      "unresolved": [
        "string"
      ]
    },
    "risk_codes": [
      "string"
    ],
    "verdict": "allow",
    "warnings": [
      "string"
    ]
  },
  "type": "string"
}

Examples

curl

curl "https://payee.schemasure.com/v1/guard/payee"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid

JavaScript

const res = await fetch("https://payee.schemasure.com/v1/guard/payee");
if (res.status === 402) {
  const { accepts } = await res.json();
  // pay one of accepts[] via an x402 client, then retry with the payment header
}

Python

import httpx
res = httpx.get("https://payee.schemasure.com/v1/guard/payee")
if res.status_code == 402:
    accepts = res.json()["accepts"]
    # pay one of accepts[] via an x402 client, then retry with the payment header

Details

Provider: payee.schemasure.com
Endpoint: https://payee.schemasure.com/v1/guard/payee
Machine-readable: /resources/36258.json