Pay-per-call kit / SDK reference

A payment request.
Not yet a receipt.

Trace the headers. Bound the spend. See exactly where chain verification is missing.

Inspect the flow Source and protocol note ↗

Payment execution is blocked. This reference has no verified chain adapter. The flow below replays recorded local headers. It is not a successful devnet payment.

Follow the request

Every step has an evidence boundary.

Recorded flow

The line tracks reading progress, not payment confirmation.

Recorded local evidence

Start with a bound request.

The request ID links retries. The server binds the method, URL, body and application headers to one quote.

Recorded object

{
  "url": "http://127.0.0.1:3350/settlements",
  "method": "GET",
  "headers": {
    "x-flop-request-id": "recorded-request-0001"
  }
}

Download the complete recording ↓

A real read-only payload

Settlement preview, without a payment.

Observed settlement rows from the hosted MCP. The arithmetic check asks whether miner payment, burn and refund add up to escrow. It does not prove chain finality or inference correctness.

Last-known recordingObserved 2026-11-05T16:24:25.688ZHosted FLOP MCP ↗

Refresh is read-only. Server cache TTL: 60 seconds.

Rows in this sample5

Escrow sums agree5 / 5

Paid service responseNot recorded

Miner payment / FLOP

Block 2,964,740Sum agrees

0.065340000000000004 FLOP

Block 2,955,987Sum agrees

0.855359999999999992 FLOP

Block 2,945,246Sum agrees

0.516780000000000021 FLOP

Block 2,893,718Sum agrees

0.302939999999999996 FLOP

Block 2,885,980Sum agrees

11.79683999999999971 FLOP

Bar length = miner payment / largest miner payment in this sample. Values remain readable during motion.

Run the reference

Bring the evidence to your terminal.

From a flop-lab checkout after pnpm install. Node 22. The demo listens on loopback.

pnpm --filter @flop-lab/x402kit build && node packages/x402kit/dist/cli.js serve 3350

Open http://127.0.0.1:3350/preview. The protected route asks for payment but cannot accept a proof without an audited adapter.

What this does not verify

The recording does not verify a merchant payment, runtime finality, TEE appraisal or standard x402 v2 interoperability. The kit checks supplied evidence and request policy. Its chain adapter remains UNVERIFIED.