Tools / Crypto & Base
Payment Proof $0.003 / call
Verify an x402 settlement end to end.
GET /v1/payment-proofThe settlement-verification headliner. Confirms a Base transaction succeeded, decodes its USDC transfers, and optionally asserts that a specific wallet received a specific amount — returning a single verdict: verified, settled-but-mismatch, or failed-onchain.
Parameters
hash required | Base transaction hash to verify |
payTo | Assert USDC was received by this wallet |
amount | Assert the USDC amount (human decimal) |
Example
macOS / Linuxcurl -s "https://quartermaster.surewhynot.app/v1/payment-proof?hash=0x06be01596be1cb68d9b12a33946d2228a82eeb31016ab237825cec547017095f&payTo=0xc2a36e22ecbf353086cf83e7beea78bc28a64083&amount=0.001"curl.exe -s "https://quartermaster.surewhynot.app/v1/payment-proof?hash=0x06be01596be1cb68d9b12a33946d2228a82eeb31016ab237825cec547017095f&payTo=0xc2a36e22ecbf353086cf83e7beea78bc28a64083&amount=0.001"Unpaid, these return 402 Payment Required with the payment details in the header (add -i to see them). curl.exe ships with Windows 10+ and works in cmd and both PowerShell versions. To actually pay, use an x402 client (see Connect) or call it as the MCP tool. Cost: $0.003 per call.
FAQ
Who needs this?
Any business or agent that takes x402 payments and needs to confirm, from a hash alone, that the right amount really reached the right wallet.
How do I pay for this endpoint?
Call it with no payment and you receive HTTP 402 with machine-readable payment requirements. Attach a USDC payment on Base with any x402 client (for example @x402/fetch) and retry — the whole loop is two requests. This call costs $0.003 in USDC.
Do I need an account or API key?
No. There are no accounts, logins, or API keys anywhere in Quartermaster. Payment is per call over the x402 protocol; your wallet is your identity.
Can I call this as an MCP tool instead?
Yes. Quartermaster is also an MCP server at /mcp, so any MCP client (Claude Code, Claude.ai, Cursor) can mount this tool. See /connect for setup.