payment-ready until 2026-09-03
Per-market liquidity authenticity + UMA resolution-risk for Polymarket prediction markets, sold to AI trading agents via x402 ($0.20/call, USDC on Base). Returns whether apparent volume is broad/organic or concentrated/manufactured (HHI, effective traders, book cross-check, on-chain counterparties) AND the UMA resolution-risk on two axes: how often a category disputes on UMA x when disputed, how often the result FLIPS the original proposal vs just confirms, plus whether the criterion is objective (checkable) or subjective. Dispute-rate and flip-rate often invert by category - a two-axis read no other tool gives. Fact/base-rate, never a wash verdict nor per-market prediction. Also two /market-authenticity/{conditionId} and /x402-authenticity/{payTo} parameterized endpoints (see /openapi.json).
Pay from $0.05 per request in USDC on Base, settled onchain via the x402 protocol, no signup, no API key needed.
VERDICT
ranking generation 3solid 86/100 #169 of 253 in Data by measured score
What the score read on this service: status online, 100% uptime 30d, 2565ms response p95, x402 compliance 14 of 14, $0.05 price against the category. 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 Data, 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 253 listings, this one among them. That set is wider than the 253 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 DATA
Other Data 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 |
|---|---|---|---|---|
| WebberSites x402 Data API | strong | 99 | 100% | --- |
| API Acre | strong | 99 | 99.9% | --- |
| ForgeMesh Utility APIs | strong | 99 | 100% | --- |
| AgentFund US Economic, SEC & On-Chain Data | strong | 99 | 100% | --- |
| AgentToll | strong | 98 | 100% | --- |
ASSESSMENT
updated 26m 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 100%
- uptime 24h
- 100%
- uptime 7d
- 100%
- uptime 30d
- 100%
- uptime 90d
- 95.2%
- response p95
- 2565ms
- avg response
- 1121ms
- total checks
- 2,700
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 $0.05 (p87 in Data)
- price (min)
- $0.05
- category percentile (min)
- p87 in Data
- endpoints / prices
- 3 / 1
- model
- flat
- stability
- 0%
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
- -
- registrar
- -
- hosting
- custom
- domain created
- ---
Identity facts, not a risk score.
traction ---
This service settles on a network x402-list does not measure yet, so on-chain volume is not counted here. Shown as unmeasured, not zero.
CHANGES
2 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 schema changed 14d ago (2 in 30d)
schema changed · 14d ago
schema removed GET /resolution-risk exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 300 {"name":"USD Coin","version":"2"}
schema removed GET /screener exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 300 {"name":"USD Coin","version":"2"}
schema removed GET /x402-market exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 300 {"name":"USD Coin","version":"2"}
schema added GET /resolution-risk exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 300 {"iconUrl":"https://polym.uk/favicon.svg","name":"USD Coin","version":"2"}
schema added GET /screener exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 300 {"iconUrl":"https://polym.uk/favicon.svg","name":"USD Coin","version":"2"}
schema added GET /x402-market exact eip155:8453 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913 USDC 2 300 {"iconUrl":"https://x402intel.uk/favicon.svg","name":"USD Coin","version":"2"}
price changed · 15d ago
GET /resolution-risk · eip155:8453 · USDC: 200000 → 50000
GET /screener · eip155:8453 · USDC: 200000 → 50000
GET /x402-market · eip155:8453 · USDC: 200000 → 50000
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 | /resolution-risk | UMA resolution-risk landscape by category: dispute base-rate × flip rate (when disputed, does it reverse?) + criterion clarity. Fact/base-rate, not prediction. | $0.05 | Base | USDC | header |
| GET | /screener | Top Polymarket markets ranked by liquidity-authenticity bucket (fact, per window) | $0.05 | Base | USDC | header |
| GET | /x402-market | The honest state of the x402 market: real value-matched size vs the hype | $0.05 | Base | USDC | header |
REQUEST / RESPONSE EXAMPLE
An unpaid request to GET /resolution-risk returns HTTP 402 with the payment terms. Settle onchain via your facilitator, then retry with the X-Payment header.
curl -i 'https://api.x402intel.uk/resolution-risk'
// 402 response (captured by monitor) · 3 payloads · click to expand
[
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"iconUrl": "https://polym.uk/favicon.svg",
"version": "2"
},
"payTo": "0x7b13107779CfDA1bEba3289d0Fbe27310436f3E3",
"amount": "50000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://api.polym.uk/screener",
"tags": [
"polymarket",
"prediction-markets",
"screener",
"order-flow",
"base"
],
"iconUrl": "https://polym.uk/favicon.svg",
"mimeType": "application/json",
"description": "Ranked Polymarket market-flow screener with factual concentration and liquidity-compatibility fields for the observed window.",
"serviceName": "Polymarket Intelligence API"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {
"top": 20
}
},
"output": {
"type": "json",
"example": {
"asOf": "2026-07-01T00:00:00.000Z",
"caveats": [
"STATIC CONTRACT SAMPLE ONLY: this payload is not live market intelligence.",
"Paid screener responses describe the observed materialized window and retain their own caveats."
],
"markets": [
{
"title": "Static contract sample — not a live Polymarket market",
"bucket": "moderate",
"resolution": {
"category": "Example",
"categoryFlipRatePct": null,
"subjectiveCriterion": false,
"categoryDisputeRatePct": 4.2
},
"conditionId": "0x1111111111111111111111111111111111111111111111111111111111111111",
"marketClosed": false,
"topTraderShare": 0.42,
"effectiveTraders": 7,
"apparentVolumeUsd": 12345.67,
"apparentVsBookFlag": false
}
],
"decomposed": 40,
"windowHours": 24,
"observedMarkets": 128
}
}
},
"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",
"properties": {
"top": {
"type": "integer",
"default": 20,
"maximum": 40,
"minimum": 1
}
},
"additionalProperties": false
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"asOf",
"windowHours",
"observedMarkets",
"decomposed",
"markets",
"caveats"
],
"properties": {
"asOf": {
"type": "string",
"format": "date-time"
},
"caveats": {
"type": "array",
"items": {
"type": "string"
}
},
"markets": {
"type": "array",
"items": {
"type": "object",
"required": [
"conditionId",
"title",
"bucket",
"apparentVolumeUsd",
"topTraderShare",
"effectiveTraders",
"apparentVsBookFlag",
"marketClosed",
"resolution"
],
"properties": {
"title": {
"type": "string",
"description": "Observed Polymarket market title."
},
"bucket": {
"enum": [
"unranked",
"structurally-thin",
"concentrated",
"moderate",
"broad"
],
"type": "string",
"description": "Descriptive taker-flow structure bucket, not a fraud verdict."
},
"resolution": {
"type": [
"object",
"null"
],
"required": [
"category",
"categoryDisputeRatePct",
"categoryFlipRatePct",
"subjectiveCriterion"
],
"properties": {
"category": {
"type": "string",
"description": "Heuristic category inferred from the market title."
},
"categoryFlipRatePct": {
"type": [
"number",
"null"
],
"maximum": 100,
"minimum": 0
},
"subjectiveCriterion": {
"type": "boolean",
"description": "True when the resolution criterion is classified as subjective."
},
"categoryDisputeRatePct": {
"type": [
"number",
"null"
],
"maximum": 100,
"minimum": 0
}
},
"additionalProperties": false
},
"conditionId": {
"type": "string",
"pattern": "^0x[0-9a-fA-F]{64}$",
"description": "Polymarket condition ID."
},
"marketClosed": {
"type": [
"boolean",
"null"
],
"description": "Whether the market was closed in the artifact."
},
"topTraderShare": {
"type": "number",
"maximum": 1,
"minimum": 0,
"description": "Share of observed taker volume attributed to the top trader."
},
"effectiveTraders": {
"type": "integer",
"minimum": 0,
"description": "HHI-derived effective trader count for the observed taker flow."
},
"apparentVolumeUsd": {
"type": "number",
"minimum": 0,
"description": "Observed taker-side volume in the materialized window, in USD."
},
"apparentVsBookFlag": {
"type": [
"boolean",
"null"
],
"description": "Whether observed volume is structurally inconsistent with available book liquidity."
}
},
"additionalProperties": false
}
},
"decomposed": {
"type": "integer",
"minimum": 0
},
"windowHours": {
"type": "number",
"minimum": 0
},
"observedMarkets": {
"type": "integer",
"minimum": 0
}
},
"additionalProperties": false
}
}
}
}
}
}
},
"x402Version": 2
},
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"iconUrl": "https://x402intel.uk/favicon.svg",
"version": "2"
},
"payTo": "0x7b13107779CfDA1bEba3289d0Fbe27310436f3E3",
"amount": "50000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://api.x402intel.uk/x402-market",
"tags": [
"x402",
"market-intelligence",
"onchain-analytics",
"usdc",
"base"
],
"iconUrl": "https://x402intel.uk/favicon.svg",
"mimeType": "application/json",
"description": "x402 market intelligence with current catalog-attributed USDC flow, address-level demand signals and separately labeled value-matched history. Attribution is not exclusive protocol-intent proof.",
"serviceName": "x402 Intelligence API"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {}
},
"output": {
"type": "json",
"example": {
"demand": {
"totalBuyers": 0
},
"market": {
"sellersOnBase": 0,
"sellersWithRealActivity": 0
},
"generatedAt": "2026-07-19T00:00:00.000Z"
}
}
},
"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",
"properties": {},
"additionalProperties": false
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"properties": {},
"additionalProperties": true
}
}
}
}
}
}
},
"x402Version": 2
},
{
"error": "Payment required",
"accepts": [
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"iconUrl": "https://polym.uk/favicon.svg",
"version": "2"
},
"payTo": "0x7b13107779CfDA1bEba3289d0Fbe27310436f3E3",
"amount": "50000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
],
"resource": {
"url": "https://api.polym.uk/resolution-risk",
"tags": [
"polymarket",
"prediction-markets",
"uma-resolution",
"base-rates",
"base"
],
"iconUrl": "https://polym.uk/favicon.svg",
"mimeType": "application/json",
"description": "UMA resolution dispute and flip base rates by category and criterion clarity; descriptive historical compatibility, not a market-specific forecast.",
"serviceName": "Polymarket Intelligence API"
},
"extensions": {
"bazaar": {
"info": {
"input": {
"type": "http",
"method": "GET",
"queryParams": {}
},
"output": {
"type": "json",
"example": {
"asOf": "2026-07-19T00:00:00.000Z",
"caveats": [
"Example only: live responses retain artifact-specific caveats and timestamps."
],
"clarity": {
"checkable": {
"disputeRatePct": 1.2,
"marketsScanned": 100
},
"subjective": {
"disputeRatePct": 4.2,
"marketsScanned": 20
}
},
"flipAsOf": null,
"howToRead": "Historical category base rates describe resolution compatibility; they are not a forecast for an individual market.",
"byCategory": [
{
"category": "Example",
"elevated": true,
"flipRatePct": null,
"lockupHoursPerMarket": null,
"lockupHoursIfDisputed": null,
"flipInsufficientSample": true,
"disputeRatePctHighVolume": 4.2,
"disputeInsufficientSample": false,
"disputeRatePctChronological": null
}
],
"flipOverall": null,
"dataDegraded": false,
"elevatedRiskCategories": [
"Example"
]
}
}
},
"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",
"properties": {},
"additionalProperties": false
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"asOf",
"flipAsOf",
"dataDegraded",
"elevatedRiskCategories",
"byCategory",
"clarity",
"flipOverall",
"howToRead",
"caveats"
],
"properties": {
"asOf": {
"type": "string",
"format": "date-time"
},
"caveats": {
"type": "array",
"items": {
"type": "string"
}
},
"clarity": {
"type": [
"object",
"null"
],
"required": [
"checkable",
"subjective"
],
"properties": {
"checkable": {
"type": "object",
"required": [
"marketsScanned",
"disputeRatePct"
],
"properties": {
"disputeRatePct": {
"type": "number",
"maximum": 100,
"minimum": 0
},
"marketsScanned": {
"type": "integer",
"minimum": 0
}
},
"additionalProperties": false
},
"subjective": {
"type": "object",
"required": [
"marketsScanned",
"disputeRatePct"
],
"properties": {
"disputeRatePct": {
"type": "number",
"maximum": 100,
"minimum": 0
},
"marketsScanned": {
"type": "integer",
"minimum": 0
}
},
"additionalProperties": false
}
},
"additionalProperties": false
},
"flipAsOf": {
"type": [
"string",
"null"
],
"format": "date-time"
},
"howToRead": {
"type": "string"
},
"byCategory": {
"type": "array",
"items": {
"type": "object",
"required": [
"category",
"disputeRatePctHighVolume",
"disputeRatePctChronological",
"disputeInsufficientSample",
"elevated",
"lockupHoursPerMarket",
"lockupHoursIfDisputed",
"flipRatePct",
"flipInsufficientSample"
],
"properties": {
"category": {
"type": "string"
},
"elevated": {
"type": "boolean"
},
"flipRatePct": {
"type": [
"number",
"null"
],
"maximum": 100,
"minimum": 0
},
"lockupHoursPerMarket": {
"type": [
"number",
"null"
],
"minimum": 0
},
"lockupHoursIfDisputed": {
"type": [
"number",
"null"
],
"minimum": 0
},
"flipInsufficientSample": {
"type": "boolean"
},
"disputeRatePctHighVolume": {
"type": "number",
"maximum": 100,
"minimum": 0
},
"disputeInsufficientSample": {
"type": "boolean"
},
"disputeRatePctChronological": {
"type": [
"number",
"null"
],
"maximum": 100,
"minimum": 0
}
},
"additionalProperties": false
}
},
"flipOverall": {
"type": [
"object",
"null"
],
"required": [
"flipRatePct",
"disputedResolved"
],
"properties": {
"flipRatePct": {
"type": "number",
"maximum": 100,
"minimum": 0
},
"disputedResolved": {
"type": "integer",
"minimum": 0
}
},
"additionalProperties": false
},
"dataDegraded": {
"type": "boolean"
},
"elevatedRiskCategories": {
"type": "array",
"items": {
"type": "string"
}
}
},
"additionalProperties": false
}
}
}
}
}
}
},
"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/polymarket-liquidity-authenticity-uma-resolution-risk/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 3 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 2026-08-12 · last up 2026-08-27
- 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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