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Payments · x402 · early usage

Verify EVM signatures offline: EIP-191 personal messages, EIP-712 typed data, and x402/…

Verify EVM signatures offline: EIP-191 personal messages, EIP-712 typed data, and x402/EIP-3009 payment authorizations (paste a raw Payment-Signature header) — recovers the signing wallet, checks it against an expected address, and reports the authorization's…

by workbot1.oddsys.org · discovered, not yet claimed by its owner · updated 2026-10-08

30d calls3
30d payers3
MethodPOST
Outputjson schema

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

Verify EVM signatures offline: EIP-191 personal messages, EIP-712 typed data, and x402/EIP-3009 payment authorizations (paste a raw Payment-Signature header) — recovers the signing wallet, checks it against an expected address, and reports the authorization's amount, payee and validity window. No chain reads.

Tags: signature · eip191 · eip712 · eip3009 · x402 · bazaar

Call contract

Method
POST
Input
json
Output
json schema
Last paid call
2026-10-08
Input example from Bazaar metadata
{
  "address": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
  "message": "Busker x402 verify-sig example",
  "signature": "0x8f83ce1348bb56eb6d7ede8f6c6787adc3897839e686a0b305fb87e7cd248d5555c7405f0e776b995be1971d6ed71a95541d19635e354f807d94c9326c22a1cb1c"
}
Output example
{
  "address": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
  "matches": true,
  "messageHash": "0x0c9b1f4d5f2b6e7a4d3c2b1a0f9e8d7c6b5a4f3e2d1c0b9a8f7e6d5c4b3a2f1e",
  "mode": "eip191",
  "signer": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
  "valid": true
}

Use with an agent

  1. Discover. Agents find this listing with GET https://bazaar.saylorinnovations.com/discovery/search?query=…, the MCP tool search_resources, or /discovery/resources.
  2. Inspect. Fetch /resources/32276.json for the price and payment options.
  3. Pay. Call GET https://workbot1.oddsys.org/verify-sig. The provider answers 402 with its payment requirements. An x402 client signs one of the options below and retries with PAYMENT-SIGNATURE.
  4. 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
$0.002 / request
Protocol
x402 v2
Auth
No account or API key. Pay per request.
Networks
Base
Demand
3 calls · 3 unique payers in 30d (public x402 Bazaar data)

x402 payment requirements

SchemeNetworkAssetAmountPay toTimeout
exactBase
eip155:8453
USDC$0.0020x15459498e1191d8787c83177809bd54022fA18c4300s
accepts[] (raw JSON)
[
  {
    "scheme": "exact",
    "network": "eip155:8453",
    "payTo": "0x15459498e1191d8787c83177809bd54022fA18c4",
    "asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "2000",
    "amountUsd": 0.002,
    "maxTimeoutSeconds": 300
  }
]

Schemas

Output schema (JSON Schema)
{
  "body": {
    "amount": "object — { usdc } for known USDC contracts",
    "authorization": "object (authorization modes) — from, to, value, validAfter, validBefore, nonce",
    "checks": "object (x402-header) — payToMatches, amountMatches, network, scheme",
    "matches": "boolean (when address given) / matchesFrom (authorization modes)",
    "messageHash": "string (eip191) / digest (typed modes)",
    "mode": "string (eip191|eip712|eip3009|x402-header)",
    "signer": "string|null — recovered EOA",
    "valid": "boolean — signature recovered to an address",
    "window": "object — { validAfter, validBefore, validNow }"
  },
  "bodyType": "json",
  "example": {
    "address": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
    "matches": true,
    "messageHash": "0x0c9b1f4d5f2b6e7a4d3c2b1a0f9e8d7c6b5a4f3e2d1c0b9a8f7e6d5c4b3a2f1e",
    "mode": "eip191",
    "signer": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
    "valid": true
  }
}
Example shape — generated from the schema, not a captured live response
{
  "address": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
  "matches": true,
  "messageHash": "0x0c9b1f4d5f2b6e7a4d3c2b1a0f9e8d7c6b5a4f3e2d1c0b9a8f7e6d5c4b3a2f1e",
  "mode": "eip191",
  "signer": "0x7E5F4552091A69125d5DfCb7b8C2659029395Bdf",
  "valid": true
}

Examples

curl
curl "https://workbot1.oddsys.org/verify-sig"
# -> 402 Payment Required, accepts[] lists how to pay
# retry with a PAYMENT-SIGNATURE (or PAYMENT header) once paid
JavaScript
const res = await fetch("https://workbot1.oddsys.org/verify-sig");
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://workbot1.oddsys.org/verify-sig")
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
workbot1.oddsys.org
Endpoint
https://workbot1.oddsys.org/verify-sig
Machine-readable
/resources/32276.json