Umpire
Verification PAYMENT-READYpayment-ready until 2026-10-06
A neutral third party for agent commerce. Buy an Ed25519 signed pass or fail verdict on a deliverable against a machine readable acceptance spec (JSON Schema, JSON path, content hash, regex, length, live URL probe), verifiable offline by anyone against a published key. The witness tier ($0.25) fetches one public URL and signs what it saw (final URL, status, resolved address, TLS fingerprint, headers, body sha256) as proof against agent false success. Also sells reputation reads on merchant wallets built only from payment verified feedback. $0.01 to $5.00 per document, USDC on Base or Solana, no account.
Pay from $0.01 to $5.00 in USDC on Base / Solana, settled onchain via the x402 protocol, no signup, no API key needed.
measured since 2026-09-03 (start of our harvest window) · $0 all-time · last settled 2026-09-24
VERDICT
ranking generation 3solid 85/100 #34 of 113 in Verification by measured score
What the score read on this service: status online, 99.9% uptime 30d, 1073ms response p95, x402 compliance 14 of 14, $0.01 price against the category, on-chain traction measured. Each of those is measured, and each is published in full below.
The score comes from our own monitoring, never from reviews, operator claims, or a language model: reliability, x402 compliance, price against the category, a deterministic risk flag, and a small on-chain traction term, weighted by ranking generation 3. It is not placement anyone can buy: the paid verify tier is reported beside it and is not one of its inputs. Every component below stays published and read-only.
It is a score inside Verification, and only there: price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, which here means 113 listings, this one among them. That set is wider than the 113 the position above is counted against, because a listing we have measured too little of to rank still sits in the field the price and the speed are normalized over. The same service in a different field would read differently. The same engine answers GET /api/v1/best, and asked for a different pool (the whole directory, or another filter) it returns a different number for this service under this same ranking generation. Neither is more correct: they answer different questions, and the methodology states which is which.
Bands on the 0 to 100 measured score: strong at 93 and above, solid from 75, mixed from 55, weak below 55. Price and speed are scored against the whole category field, every listing in it that carries no danger flag, the scored service included, so the score places a service in its own field.
ALTERNATIVES IN VERIFICATION
Other Verification services in this directory, ordered by the same measured score. The figures are ours: 30-day uptime from our own probes, 30-day settlement volume read on-chain (a conservative undercount, and null where we cannot measure it, never a zero).
| SERVICE | BAND | SCORE | UPTIME 30D | VOL 30D |
|---|---|---|---|---|
| scvd.store — evidence observatory for the x402 economy | strong | 94 | 100% | $918.33 |
| Rubric Protocol — Post-Quantum AI Attestation | solid | 93 | 99.8% | $33.21 |
| Enclave402 | solid | 89 | 100% | $3.98 |
| LION — Verified Company & Compliance Data | solid | 89 | 100% | $5.80 |
| 767-2676.com - POPCORN | solid | 89 | 100% | $0.11 |
ASSESSMENT
updated 6h agoThe parts the verdict above is computed from, each with its proof. Click any chip. Measured values stay read-only; unknown is honest, and an unknown is never counted as a zero.
reliability 99.9%
- uptime · latest daily rollup
- 100%
- uptime 7d
- 100%
- uptime 30d
- 99.9%
- uptime 90d
- 99.9%
- response p95
- 1073ms
- avg response
- 300ms
- total checks
- 1,271
Measured on the unpaid 402 handshake, not the paid call. A service can 402 correctly and still fail after payment.
compliance A (14/14)
14 of 14 x402 conformance checks pass. Full checklist below.
price $0.01 to $5.00 (p44 in Verification)
- price (min)
- $0.01
- price (max)
- $5.00
- category percentile (min)
- p44 in Verification
- category percentile (max)
- p95 in Verification
- endpoints / prices
- 5 / 5
- model
- tiered
- stability
- 100%
risk clean
No deterministic risk flag. Risk fires only on an exact blocklist match, or a reserved-brand name with a mismatched verified payTo. Never from low uptime, a high price, or a model guess.
- domain age
- 59d
- registrar
- Cloudflare, Inc.
- hosting
- custom
- domain created
- 2026-07-24
Identity facts, not a risk score.
traction $0.00 30d · 0 buyers
- volume 30d
- $0.00
- buyers 30d
- 0
- settlements 30d
- 0
- measured since
- 2026-09-03 (start of our harvest window)
- last settlement
- 2026-09-24
- top buyer share
- -
- trend 7d vs 30d
- -
- networks
- eip155:8453, solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdpKuc147dw2N9d
- volume all-time
- $0
- settlements all-time
- 0
- median settlement 30d
- -
- max settlement 30d
- -
- settled via
- -
Conservative undercount: only USDC settlements via facilitators we measure are counted. A measured floor, not an estimate.
Top buyer share is part of the ranking score: a higher share lowers the traction part of the score, by up to half when one address holds all 30d volume.
CHANGES
5 in 30dPayout, price, and schema changes detected on this service's x402 wire. A payout rotation at an unchanged price shows up here even when nothing else moves. Full feed at /changes.
changes price changed 32h ago (5 in 30d)
price changed · 32h ago
GET /v1/reputation · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 83519 → 82394
GET /v1/verdicts/basic · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 8351848 → 8239306
GET /v1/verdicts/probe · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 16703695 → 16478611
GET /v1/verdicts/sworn · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 41759237 → 41196526
GET /v1/verdicts/witness · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 2087962 → 2059827
price changed · 3d ago
GET /v1/reputation · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 85622 → 83389
GET /v1/verdicts/basic · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 8562150 → 8338811
GET /v1/verdicts/probe · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 17124299 → 16677621
GET /v1/verdicts/sworn · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 42810747 → 41694052
GET /v1/verdicts/witness · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 2140538 → 2084703
price changed · 6d ago
GET /v1/reputation · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 86350 → 85622
GET /v1/verdicts/basic · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 8634991 → 8562150
GET /v1/verdicts/probe · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 17269982 → 17124299
GET /v1/verdicts/sworn · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 43174955 → 42810747
GET /v1/verdicts/witness · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 2158748 → 2140538
price changed · 7d ago
GET /v1/reputation · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 104505 → 86350
GET /v1/verdicts/basic · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 10450451 → 8634991
GET /v1/verdicts/probe · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 20900901 → 17269982
GET /v1/verdicts/sworn · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 52252253 → 43174955
GET /v1/verdicts/witness · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 2612613 → 2158748
price changed · 13d ago
GET /v1/reputation · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 98087 → 104505
GET /v1/verdicts/basic · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 9808659 → 10450451
GET /v1/verdicts/probe · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 19617318 → 20900901
GET /v1/verdicts/sworn · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 49043294 → 52252253
GET /v1/verdicts/witness · solana:5eykt4usfv8p8njdtrepy1vzqkqzkvdp · UNKNOWN: 2452165 → 2612613
Amounts are on-wire atomic units in the named asset.
WHAT IT DOES
ai-derivedNo AI synthesis has been produced for this service yet.
ENDPOINTS
| METHOD | PATH | DESCRIPTION | PRICE | NETWORK | ASSET | 402 CHANNEL |
|---|---|---|---|---|---|---|
| GET | /v1/reputation | $0.01 | Base/Solana | USDC | header | |
| GET | /v1/verdicts/basic | $1.00 | Base/Solana | USDC | header | |
| GET | /v1/verdicts/probe | $2.00 | Base/Solana | USDC | header | |
| GET | /v1/verdicts/sworn | $5.00 | Base/Solana | USDC | header | |
| GET | /v1/verdicts/witness | $0.25 | Base/Solana | USDC | header |
REQUEST / RESPONSE EXAMPLE
An unpaid request to GET /v1/reputation returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.
curl -i 'https://umpire.vimabrosta.com/v1/reputation'
// 402 response (captured by monitor) · 5 payloads · click to expand
[
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xd63e74bCB00757C8fDb1817F1558ed8b97C608b6",
"amount": "1000000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "1000000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
},
{
"asset": "So11111111111111111111111111111111111111112",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "8624719",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://umpire.vimabrosta.com/v1/verdicts/basic",
"mimeType": "application/json",
"description": "Get a signed pass/fail verdict on a deliverable against your acceptance spec, synchronously. Deterministic checks only: JSON Schema conformance, JSON path assertions, sha256 content hash, regex, length bounds. Returns an Ed25519 signed verdict document any third party can verify offline; suitable as evidence for escrow release. $1.00 per verdict, no account."
},
"x402Version": 2
},
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xd63e74bCB00757C8fDb1817F1558ed8b97C608b6",
"amount": "250000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "250000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
},
{
"asset": "So11111111111111111111111111111111111111112",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "2156180",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://umpire.vimabrosta.com/v1/verdicts/witness",
"mimeType": "application/json",
"description": "Proof that the world changed the way your agent says it did. One live probe of a public URL against your expectation (HTTP status, keyword, CSS selector, JSON path), answered synchronously as an Ed25519 signed verdict that embeds a signed observation: final URL, resolved address, TLS certificate fingerprint, response headers, raw body sha256, timestamp. A stake free witness against false success, priced to clear unattended wallet caps. $0.25 per verdict, no account."
},
"x402Version": 2
},
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xd63e74bCB00757C8fDb1817F1558ed8b97C608b6",
"amount": "2000000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "2000000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
},
{
"asset": "So11111111111111111111111111111111111111112",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "17249438",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://umpire.vimabrosta.com/v1/verdicts/probe",
"mimeType": "application/json",
"description": "Signed verdict with live verification: everything in basic plus up to three network probes of public URLs (HTTP status, keyword, CSS selector, JSON path on the response). Use it to verify a delivered site, API, or published artifact actually works before releasing escrow. Synchronous, Ed25519 signed, verifiable offline. $2.00 per verdict, no account."
},
"x402Version": 2
},
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xd63e74bCB00757C8fDb1817F1558ed8b97C608b6",
"amount": "5000000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "5000000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
},
{
"asset": "So11111111111111111111111111111111111111112",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "43123593",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://umpire.vimabrosta.com/v1/verdicts/sworn",
"mimeType": "application/json",
"description": "Highest assurance verdict: all checks run twice, spaced about a minute apart, and pass only if both passes pass, so a deliverable staged briefly cannot sneak through. Asynchronous: instant first pass result, webhook or free polling for the signed final document. Designed for the ERC-8183 evaluator role and escrow release evidence. $5.00 per verdict."
},
"x402Version": 2
},
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xd63e74bCB00757C8fDb1817F1558ed8b97C608b6",
"amount": "10000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 120
},
{
"asset": "EPjFWdd5AufqSSqeM2qN1xzybapC8G4wEGGkZwyTDt1v",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "10000",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
},
{
"asset": "So11111111111111111111111111111111111111112",
"extra": {
"feePayer": "BFK9TLC3edb13K6v4YyH3DwPb5DSUpkWvb7XnqCL9b4F"
},
"payTo": "8c9r8kxtkcsv7wARq3wBy2csm1ySRQQmdy6hrPnga4qs",
"amount": "86248",
"scheme": "exact",
"network": "solana:5eykt4UsFv8P8NJdTREpY1vzqKqZKvdp",
"maxTimeoutSeconds": 120
}
],
"resource": {
"url": "https://umpire.vimabrosta.com/v1/reputation",
"mimeType": "application/json",
"description": "Read the payment verified reputation of any merchant wallet address. Every score aggregates only feedback whose submitter proved a settled on-chain USDC payment to that merchant (at least the published floor) and signed with the paying wallet, so no row is free and wash patterns are exposed by independence signals. Returns a signed report: outcome counts, count and amount weighted fulfillment rates, unique payers, volume, payer concentration. $0.01 per read."
},
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"merchant": "0x1234567890abcdef1234567890abcdef12345678"
}
},
"output": {
"type": "json",
"example": {
"merchant": "0x1234567890abcdef1234567890abcdef12345678",
"feedback_count": 12,
"fulfillment_rate": 0.917,
"weighted_fulfillment_rate": 0.94
}
}
},
"name": "Umpire",
"tags": [
"verification",
"verdict",
"evaluator",
"witness",
"reputation",
"receipts",
"trust"
],
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method"
],
"properties": {
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"GET"
],
"type": "string"
},
"queryParams": {
"type": "object",
"required": [
"merchant"
],
"properties": {
"merchant": {
"type": "string",
"pattern": "^0x[0-9a-fA-F]{40}$"
}
}
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object"
}
}
}
}
},
"discoverable": true
}
},
"x402Version": 2
}
] OVER TIME
All charts use the 30d selector; each series spans only the dates it has data for. Every series is also served as JSON at /api/v1/services/umpire/price, /scores, /volume and /buyers. On-chain volume and distinct buyers are measured over the service's settlement address and are a conservative undercount (only settlements that reach a measured facilitator are counted). The on-chain series roll up hourly, so the latest day can be up to about an hour behind; distinct buyers are counted per payout address, so a service that settles to more than one address is an upper bound.
Median across 5 endpoints. Use the selector to isolate one.
checklist grew 11->14 on 2026-07-28; a step here is a metric change, not a regression
Measured site and economics pillars from the assessment history, so the latest value shown elsewhere on this page reads as a point on a trend rather than a permanent state.
COMPLIANCE
14/14 checks pass · grade Alast 402 captured 2026-09-29 · last up 2026-09-29
- 402 payload captured
- accepts[] array present
- payTo address recoverable
- payTo at accepts[0].payTo (conformant shape)
- payTo is a valid on-chain address
- atomic price declared
- atomic price in a sane range
- asset (token) address declared
- network resolves to CAIP-2
- payment scheme declared
- served over HTTPS
- declares the current x402 version (2)
- EIP-712 domain parameters present on every EVM entry
- x402 v2 envelope delivered in the payment-required header
SITE PILLARS
- homepage reachable
- openapi doc
- pricing page
- llms.txt
- robots.txt
- terms page
recent checks (18) live · click to expand
EMBED THIS BADGE
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