Experiment · x402 · Live ledger
Has an independent AI agent paid Harpd yet?
Everything else on this site is infrastructure: an endpoint that answers HTTP 402, a facilitator that settles USDC on Base, a manifest an agent can read without an account. None of it proves the one thing that matters — that an agent nobody here controls will find Harpd, pay for something, and then pay again. These two numbers are that proof, or the absence of it.
The scoreboard
Reading the payment ledger…
What counts, and what never will
The rule is published next to the number on purpose: a KPI that can be satisfied by its own operator is not a measurement. A payment counts only when all of this is true.
Counted: A settled USDC payment on Base mainnet (eip155:8453) that is not first-party, recorded in the payment ledger with payment_status = settled.
Not counted:
- Testnet settlements (Base Sepolia) — measured and shown separately, never counted.
- First-party traffic: requests carrying the shared operator marker, i.e. Harpd self-tests and CI runs.
- Unsettled requests: 402 challenges issued, rejections, and replays of an already-used payment (409).
- Free endpoint calls, which never reach the payment rail.
Repeat means the same payer came back and paid a second time — two different agents paying once each is adoption, not a repeat purchase, and is reported as two payers rather than as a repeat.
How to read a zero
A zero here is the expected state, not a failure. It means the ledger has no settled mainnet payment from a wallet that is not ours. It does not mean the payment rail is broken — that is a different signal, published separately at the payment health endpoint. If the ledger itself cannot be read, this page says UNAVAILABLE rather than printing a zero, because "we cannot see" and "nobody paid" are different facts and only one of them is reassuring.
Verify it yourself
The scoreboard is a thin view over one public endpoint. Read it directly:
curl -s https://api.harpd.com/api/agent/v1/experiment