Quartermaster

Tools / Crypto & Base

Transaction Decoder $0.003 / call

Decode a Base transaction's calldata into a readable call.

GET /v1/tx-decode

Fetches a Base transaction and decodes its input into the function it called and the arguments it passed — ERC-20 transfer/approve plus the EIP-3009 transferWithAuthorization that x402 settlements use. Point it at a settlement hash and it recognizes it: 'USDC transferWithAuthorization of 0.005 USDC (x402 settlement)'. Unknown selectors return the raw 32-byte words so you can decode them yourself.

Parameters

hash requiredBase transaction hash to decode

Example

macOS / Linux 
curl -s "https://quartermaster.surewhynot.app/v1/tx-decode?hash=0x06be01596be1cb68d9b12a33946d2228a82eeb31016ab237825cec547017095f"
Windows (cmd or PowerShell) 
curl.exe -s "https://quartermaster.surewhynot.app/v1/tx-decode?hash=0x06be01596be1cb68d9b12a33946d2228a82eeb31016ab237825cec547017095f"

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

How is this different from Transaction Status?
Status tells you whether a transaction succeeded and how many confirmations it has. Decode tells you what it actually did — which function, which arguments, how much USDC moved.
Which calls does it recognize by name?
ERC-20 transfer, transferFrom, and approve, plus EIP-3009 transferWithAuthorization / receiveWithAuthorization and permit — the calls that matter for payments and x402 settlement. Any other selector still returns the decoded raw words.
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.

← All tools · Connect to an agent · OpenAPI