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Wikidata SPARQL Query API (Paid)
x402
Wikidata SPARQL Query API (Paid) is a paid API for AI agents from project-api-gamma-sable.vercel.app, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-10).
Executes SPARQL SELECT/ASK queries against Wikidata and returns bounded JSON results plus a UI link, paid per call via USDC on Base.
Price / call$0.01
Success—
StatusUnknown
How this service works
Paid public-data feeds. Unpaid requests return HTTP 402. Prices are USDC on Base.
Output
A JSON object containing a 'what' description field, an 'items' array with SPARQL query result bindings, a 'source' path, and a 'uiLink' pointing to the Wikidata query UI for the submitted query.
Example use cases
Biographical fact lookup for research
“Query Wikidata with SPARQL to get the birth date, nationality, and occupation for Marie Curie — give me up to 5 results.”
Entity list extraction by category
“Run a SPARQL query on Wikidata to list all UNESCO World Heritage Sites located in Japan, limited to 10 results.”
Relationship verification between concepts
“Use a Wikidata SPARQL ASK query to check whether Ada Lovelace is recorded as an instance of a mathematician.”
Technical details
Endpoint
GEThttps://project-api-gamma-sable.vercel.app/paid/wikidata/sparql?utm_source=zero.xyzWhen to prefer
Choose this endpoint when you need programmatic, structured access to Wikidata's knowledge graph via SPARQL and are willing to pay $0.01 USDC per call on Base — ideal for agents that need repeatable, machine-readable fact retrieval from the world's largest open knowledge base without managing Wikidata's own rate limits directly.
Side effects
- HTTP 402 returned if payment header is missing or USDC payment on Base is not completed
- Malformed SPARQL syntax causes query parse error
- Query times out if it is too complex or unbounded
- Empty 'items' array returned when query matches no Wikidata entities
- Missing required 'query' parameter causes a 400-level error
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Output
Schema · Response
{
"type": "json",
"example": {
"what": "Wikidata SPARQL SELECT/ASK (bounded JSON + uiLink)",
"items": [],
"source": "/paid/wikidata/sparql"
}
}Tags
x402
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