market-probability
What does the market think? Ask any event question in plain English and get the implied probability from live Polymarket and Kalshi prediction markets: per-venue odds, a liquidity-weighted consensus forecast, and a cross-venue divergence flag.
TradingLiveeip155:8453Exactvia cdp
Prediction-marketsPolymarketKalshiProbabilityForecasting
Calls · 30d
4→ 0%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 30 snapshots so far.
$0.54
Verified settled volume
68 settlements proven x402 by their on-chain EIP-3009 marker.
$0.015
Listed price
As published in the catalog. Always read the live 402 before paying.
3
Calls · 30d
Upstream's own call count for this endpoint, not ours.
2
Unique payers · 30d
Last called 2026-09-05 03:16Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0x737426d3eD53930B889b3f61774669a0FDf3BE54The wallet the 402 directs payment to. Its whole payment record — every payer, every chain — is on the merchant page.
Asset 0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913
Provider
The payTo wallet does not resolve to a registered ERC-8004 agent. That is not a verdict on the service — most of the catalog is unregistered.
Accepts
The payment requirements as published to the catalog. Read the live 402 before paying — a price here is a claim, not a quote.
0.015USDC≈ $0.015 USD
on Base · exact scheme
Pay 0.015 USDC on Base to 0x7374…3BE54. The signed payment is good for 1 minute.
- Paid to
- 0x7374…3BE54
- USD Coin contract
- 0x8335…02913
- Payment window
- 1 minute
- As published
- 15000 smallest units
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0x737426d3eD53930B889b3f61774669a0FDf3BE54",
"amount": "15000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 60
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"body": {
"q": "Will the Fed cut rates before September 2026?",
"maxMarkets": 4
},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"asOf": "2026-07-31T12:00:00.000Z",
"query": "Will the Fed cut rates before September 2026?",
"source": "index",
"markets": [
{
"id": "fed-rate-cut-september-2026",
"url": "https://polymarket.com/event/fed-rate-cut-september-2026",
"venue": "polymarket",
"status": "open",
"volume": 1850000,
"question": "Will the Fed cut interest rates before September 2026?",
"closeTime": "2026-09-01T00:00:00.000Z",
"liquidity": 412000,
"matchScore": 0.91,
"probability": 0.64
},
{
"id": "KXFEDDECISION-26SEP",
"url": "https://kalshi.com/markets/kxfeddecision-26sep",
"venue": "kalshi",
"status": "open",
"volume": 240000,
"question": "Fed cuts rates at or before the September 2026 meeting",
"closeTime": "2026-09-17T00:00:00.000Z",
"liquidity": 88000,
"matchScore": 0.83,
"probability": 0.59
}
],
"confidence": 0.82,
"divergence": 0.05,
"attribution": "Implied probabilities and resolution status are derived from public Polymarket and Kalshi market data by x402.fenixfoundry.com. Not affiliated with, endorsed by, or a data feed of either venue. Informational only, not investment advice.",
"probability": 0.6312
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"required": [
"q"
],
"properties": {
"q": {
"type": "string",
"maxLength": 500,
"minLength": 3,
"description": "Natural-language description of the event you want odds for, e.g. \"Will the Fed cut rates before September 2026?\". Matched against Polymarket and Kalshi market questions."
},
"maxMarkets": {
"type": "integer",
"default": 6,
"maximum": 10,
"minimum": 1,
"description": "Maximum number of matched markets to aggregate and return (top-K by match quality). Defaults to 6."
}
},
"additionalProperties": false
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"required": [
"probability",
"confidence",
"markets",
"divergence",
"asOf",
"attribution"
],
"properties": {
"asOf": {
"type": "string"
},
"query": {
"type": "string"
},
"source": {
"enum": [
"index",
"live"
],
"type": "string"
},
"markets": {
"type": "array",
"items": {
"type": "object",
"required": [
"venue",
"id",
"question",
"url",
"probability"
],
"properties": {
"id": {
"type": "string",
"description": "Polymarket slug or Kalshi ticker."
},
"url": {
"type": "string"
},
"venue": {
"enum": [
"polymarket",
"kalshi"
],
"type": "string"
},
"status": {
"enum": [
"open",
"closed",
"resolved"
],
"type": "string"
},
"volume": {
"type": [
"number",
"null"
]
},
"question": {
"type": "string"
},
"closeTime": {
"type": [
"string",
"null"
]
},
"liquidity": {
"type": [
"number",
"null"
]
},
"matchScore": {
"type": "number"
},
"probability": {
"type": "number"
}
}
},
"description": "Top-K matched markets only, never a bulk market dump."
},
"confidence": {
"type": "number",
"description": "0..1 — match quality x venue coverage x liquidity."
},
"divergence": {
"type": [
"number",
"null"
],
"description": "Highest minus lowest venue probability; a large value means the venues disagree."
},
"attribution": {
"type": "string"
},
"probability": {
"type": [
"number",
"null"
],
"description": "Liquidity-weighted cross-venue implied probability, 0..1. Null when no market matched."
}
}
}
}
}
}
}
}
}Provenance
- Seen in the source catalog
- 2026-09-05 03:16Z
- Last indexed by Roundhouse
- 2026-09-24 12:10Z
- Last enriched (probe, favicon, geo)
- 2026-09-13 15:45Z
- x402 version
- 2
- Max timeout
- 60s
- Liveness probe
- HTTP 402
Hand this page to an agent
Copy the prompt and paste it into Claude, an MCP client or your own agent — it will vet this service and call it over the free read API. No key, no account.
GET api.roundhouseai.io/v0/endpoints
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 30 snapshots so far. Verified volume counts only settlements with an on-chain EIP-3009 marker.
Show the promptHide the prompt
Using Roundhouse, look up the x402 service market-probability and tell me whether it is worth paying: what a call costs, whether the endpoint answered when last probed, and what its payment record actually shows. curl -s 'https://api.roundhouseai.io/v0/endpoints?q=market-probability' curl -s 'https://api.roundhouseai.io/v0/merchants/<the payTo wallet returned above>' Then call it: read the price from the live 402 at https://x402.fenixfoundry.com/probability, never from a cached figure, and pay with an x402 client. The /v0 API needs an API key (`authorization: Bearer rh_live_…`) on everything except /v0/unified* and /v0/endpoints. Mint a personal key for $0.01 at GET https://api.roundhouseai.io/v0/test/x402, or use an organization key from https://roundhouseai.io/dashboard/team. If you do not have Roundhouse tools or skills installed, read https://roundhouseai.io/skill.md first — it is the whole procedure.