chess402.vercel.app
Today's Lichess daily puzzle: source game, themes, initial position, solution moves, and rating.
OtherLiveeip155:8453Exactvia cdp
Calls · 30d
1→ 0%
This endpoint's own trailing-30-day call count, as published by the upstream catalog and snapshotted daily. 27 snapshots so far.
$40.48
Verified settled volume
113 settlements proven x402 by their on-chain EIP-3009 marker.
$0.0010
Listed price
As published in the catalog. Always read the live 402 before paying.
1
Calls · 30d
Upstream's own call count for this endpoint, not ours.
1
Unique payers · 30d
Last called 2026-09-12 16:46Z
—
Upstream on-chain volume
Reported by the source catalog.
Paid to
0xfbd46201267609ad3c66bd1b99b7f1cc80b1852fThe 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.
0.001USDC≈ $0.001 USD
on Base · exact scheme
Pay 0.001 USDC on Base to 0xfbd4…1852f. The signed payment is good for 5 minutes.
- Paid to
- 0xfbd4…1852f
- USD Coin contract
- 0x8335…02913
- Payment window
- 5 minutes
- As published
- 1000 smallest units
The catalog’s raw entry
[
{
"asset": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
"extra": {
"name": "USD Coin",
"version": "2"
},
"payTo": "0xfbd46201267609ad3c66bd1b99b7f1cc80b1852f",
"amount": "1000",
"scheme": "exact",
"network": "eip155:8453",
"maxTimeoutSeconds": 300
}
]Extensions
{
"bazaar": {
"info": {
"input": {
"body": {},
"type": "http",
"method": "POST",
"bodyType": "json"
},
"output": {
"type": "json",
"example": {
"game": {
"id": "exampleId"
},
"puzzle": {
"id": "exampleId",
"rating": 1500,
"themes": [
"mateIn2",
"short"
],
"solution": [
"e2e4",
"e7e5"
]
}
}
}
},
"schema": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"input"
],
"properties": {
"input": {
"type": "object",
"required": [
"type",
"method",
"bodyType",
"body"
],
"properties": {
"body": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"properties": {},
"description": "No parameters required. Send `{}` or an empty body.",
"additionalProperties": false
},
"type": {
"type": "string",
"const": "http"
},
"method": {
"enum": [
"POST",
"PUT",
"PATCH"
],
"type": "string"
},
"bodyType": {
"enum": [
"json",
"form-data",
"text"
],
"type": "string"
}
},
"additionalProperties": false
},
"output": {
"type": "object",
"required": [
"type"
],
"properties": {
"type": {
"type": "string"
},
"example": {
"type": "object",
"$schema": "https://json-schema.org/draft/2020-12/schema",
"required": [
"game",
"puzzle"
],
"properties": {
"game": {
"type": "object",
"required": [
"id"
],
"properties": {
"id": {
"type": "string",
"description": "Lichess game id the puzzle was extracted from."
},
"pgn": {
"type": "string",
"description": "PGN of the game up to the puzzle position."
}
},
"description": "Source game for the puzzle.",
"additionalProperties": {}
},
"puzzle": {
"type": "object",
"required": [
"id",
"rating",
"solution"
],
"properties": {
"id": {
"type": "string",
"description": "Puzzle id."
},
"rating": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "Puzzle difficulty rating."
},
"themes": {
"type": "array",
"items": {
"type": "string"
},
"description": "Tactical themes labeled on this puzzle."
},
"solution": {
"type": "array",
"items": {
"type": "string"
},
"description": "Sequence of UCI moves that solve the puzzle."
},
"initialPly": {
"type": "integer",
"maximum": 9007199254740991,
"minimum": -9007199254740991,
"description": "Ply count at puzzle start position."
}
},
"description": "Puzzle metadata and solution.",
"additionalProperties": {}
}
},
"description": "Daily puzzle response.",
"additionalProperties": {}
}
}
}
}
}
}
}Provenance
- Seen in the source catalog
- 2026-09-12 16:46Z
- Last indexed by Roundhouse
- 2026-09-24 14:40Z
- Last enriched (probe, favicon, geo)
- 2026-09-22 01:45Z
- x402 version
- 2
- Max timeout
- 300s
- Liveness probe
- HTTP 405
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. 27 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 chess402.vercel.app 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=chess402.vercel.app' 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://chess402.vercel.app/api/puzzle/daily, 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.