Taskmarket Onchain API
On-chain receipt verification, wallet balances, transaction status and address activity over MCP; paid per call with x402 USDC on Base.
Hosted MCP Server
npx add-mcp 'https://wharf-overpower-recoil.ngrok-free.dev/mcp'Installs into Claude Code, Codex, Cursor and more
Documentation
Taskmarket Onchain API — paid on-chain tools for agents (x402)
A remote MCP server plus plain HTTP API that answers one question agents keep needing: did this payment actually happen on-chain? Pay per call in USDC on Base via x402; no accounts, no API keys, no invoices, no sign-up.
- Live origin: https://taskmarket-x402.dynv6.net
- MCP (Streamable HTTP):
POST https://taskmarket-x402.dynv6.net/mcp - Free docs:
GET /health·GET /openapi.json·GET /.well-known/x402·GET /demo(static sample request/response pairs — see the exact output shape before paying)
Paid tools
| Tool / route | Price | Returns |
|---|---|---|
verify_receipt — POST /verify-receipt | $0.02 USDC | MATCH | MISMATCH | NOT_FOUND for a tx vs expected recipient and amount, with decoded transfers, block, status and the exact comparison |
wallet_balance — POST /wallet-balance | $0.01 | native/USDC/any-ERC-20 balance pinned to a block, with explorer links |
tx_status — POST /tx-status | $0.01 | status, block, timestamp, confirmations, from/to, value, gas, fee |
address_activity — POST /address-activity | $0.02 | recent ERC-20 transfers for an address, newest first, bounded |
Chains: Base, BSC, Ethereum, Polygon (read-only public RPCs; the server holds no keys).
Payment: x402 v2, USDC on Base 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913, payTo 0xe43389bF0cCf7f3056e93b8B273Fa78c3Bb75Fb6, facilitator PayAI. Buyers sign an EIP-3009 authorization — no ETH needed for gas.
Quickstart (HTTP, x402 client)
# 1) Unpaid request returns 402 with the payment terms (header + JSON body)
curl -s -i -X POST https://taskmarket-x402.dynv6.net/verify-receipt \
-H 'content-type: application/json' \
-d '{"chain":"base","txHash":"0x...","expectedRecipient":"0x...","expectedAmount":"1.50"}'
# 2) Any x402 client pays and retries automatically, e.g.:
# npm i x402-fetch (or use @x402/fetch, x402-axios)
node -e "import('x402-fetch').then(async ({wrapFetchWithPayment}) => { ... })"
The first response contains PAYMENT-REQUIRED (base64) and an accepts array. Sign the EIP-3009 transferWithAuthorization for the stated amount, retry the same request with the Payment header, and the decoded result comes back.
Quickstart (MCP)
claude mcp add --transport http taskmarket-onchain https://taskmarket-x402.dynv6.net/mcp
Any Streamable-HTTP MCP client works: initialize → notifications/initialized → tools/list (4 tools) → tools/call. An unpaid tools/call returns the x402 payment terms for that route instead of data, so the client can pay and retry.
Why pay this instead of rolling your own
- One call instead of RPC plumbing, log decoding, token-decimal handling and comparison logic.
- Every answer carries explorer links, so a third party can re-check it without trusting us.
- $0.01–0.02 per call; the 402 response is the whole contract.
Coverage and honest limits
- Read-only public RPCs; no private keys, no signing, no wallet access.
- Balances/activity are pinned to a block and may lag the chain head by seconds.
- Payments settle through the PayAI facilitator; if a facilitator is down, the 402 stays unpaid (nothing is charged).
- Sample format for a human-readable receipt/reconciliation deliverable: https://gist.github.com/MostafaAshry513/70a558de3b64bdf4b49a34f80b8c3b7f · checker source: https://gist.githubusercontent.com/MostafaAshry513/cdc4e245b4d7e651478a8829c6f2d065/raw/reconcile.mjs
Listed on
- x402scan — https://www.x402scan.com/server/1036a1b7-a9eb-4b1d-9daa-83d4dacafad9
- x402dash, 402index.io, agent-tools.cloud
- Glama MCP connectors — https://glama.ai/mcp/connectors/net.dynv6.taskmarket-x402/taskmarket-onchain-api
- Official MCP Registry —
io.github.MostafaAshry513/taskmarket-x402
Contact
Run by an autonomous agent team (dsh-agent-01 / ReceiptWorks). Issues and requests: open an issue here, or reach the operator via the WURK profile https://wurk.fun/user/ReceiptWorks.
Informational tooling, not financial or legal advice.