Umpire
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§ · fee schedule · effective September 2026

Priced per document. Nothing recurring.

Six instruments, each one purchase, priced in USD and settled in USDC over x402 on Base or Solana. No account, no key, no subscription. The same table as JSON lives at /pricing.json, which is what an agent reads, and every 402 response quotes the exact amount before any money moves.

currency USDC (or native SOL, quoted per request) protocol x402, exact scheme refunds none once a document is issued; refusals cost nothing

01Schedule of fees

One line per instrument; the route is what an agent calls
routewhat it buysfee
GET /v1/reputationThe signed reputation report for any merchant wallet: outcome counts, fulfillment rate, unique payers, attested volume, and payer concentration. Read it before paying a stranger.$0.01
POST /v1/verdicts/witnessOne live probe of a public URL against your expectation, answered with a signed observation of what was seen: final URL, peer address, TLS certificate, headers, raw body hash, time.$0.25
POST /v1/verdicts/basicDeterministic checks on a submitted deliverable: JSON Schema conformance, JSON path assertions, content hash, regex, and length bounds. Synchronous, signed.$1.00
POST /v1/verdicts/probeEverything in basic, plus up to three live probes of public URLs: HTTP status, keyword, CSS selector, and JSON path on the response.$2.00
POST /v1/verdicts/swornEvery check runs twice, spaced about 60 seconds apart, and must pass both times. Signed final document by webhook or free polling.$5.00
POST /v1/feedbackRecording feedback about a merchant you provably paid. Requires the settled transaction hash and a signature from the paying wallet. One feedback per payment.free
How the fee is charged

Send the request with no payment and read the 402: it carries every accepted payment option (network, asset, amount, payTo). Pay one and retry the identical request. A request that cannot run is refused before settlement with a corrective error, so a malformed spec, an unreachable probe target, or a bad address costs nothing. The Idempotency-Key header is honored on paid requests, so a network retry never buys the same verdict twice.

02Reading the table

A verdict is a signed opinion about a deliverable against a spec you wrote; the tier sets how much is checked and how carefully. The reputation read is the cheapest thing here and the one to buy first: what payers who provably paid a merchant said afterwards, aggregated. Feedback is free because it is the raw material of reputation, and it is gated by a settled payment and a wallet signature so it cannot be farmed.

Every paid response is an Ed25519 signed document that anyone can verify offline against the key at /.well-known/umpire-key.json. Prices are fixed in USD; native SOL amounts are quoted per request from a cached spot rate plus a small buffer, rounded up.

03The same figures, elsewhere