# Wikidata Entity Search API

> Wikidata Entity Search API is a paid API for AI agents from api.x402node.dev, paid per call via x402, $0.005/call, status unknown (last checked 2026-09-14).

Search Wikidata's structured knowledge graph to retrieve canonical entity IDs (Q-numbers), labels, descriptions, aliases, and Linked Data IRIs for entity disambiguation

## Facts

- Endpoint: GET https://api.x402node.dev/knowledge/wikidata
- Price: $0.005/call
- Payment: x402
- Status: unknown
- Last checked: 2026-09-14
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/api-x402node-dev-011ff50b
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_NG_CjZSmYblHM5P1UTKfD

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability api-x402node-dev-011ff50b
```

Example prompt: What is the Wikidata Q-number and canonical description for 'Marie Curie'? Search in English and return up to 5 results so I can confirm the right entity.

## When to prefer this

Use this endpoint when you need canonical Wikidata entity identifiers (Q-numbers) or Linked Data IRIs for named entity disambiguation, knowledge graph enrichment, or semantic web applications. Prefer this over free-text search when you need structured, interoperable entity references rather than prose descriptions. Ideal for AI agents that need to resolve ambiguous entity names to a single authoritative identifier before querying additional knowledge sources.

## Known failure modes

- Query string too vague returns many unrelated entities with low confidence disambiguation
- Unsupported language code returns error or falls back to English
- Zero results returned when query is highly specific or misspelled
- Rate limiting or payment failure returns HTTP 402 or 429
- Ambiguous queries (e.g. common names) return multiple plausible entities requiring additional filtering

## How this service works

Search Wikidata entities (structured knowledge graph). Returns entity id (Q-number), label, description, concept URI, aliases. Use ?q=YOUR_QUERY plus optional and lang=en and limit=10. Built for AI agents needing canonical entity disambiguation and Linked Data IRIs. Accepts payment on Base or Solana — either network works.

## Output

Returns a JSON object containing one or more Wikidata entities, each with its Q-number (entity ID), human-readable label, short description, canonical concept URI (Linked Data IRI), and any known aliases — enabling precise entity disambiguation.

## Request schema (JSON Schema)

```json
{
 "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": [
      "q"
     ],
     "properties": {
      "q": {
       "type": "string",
       "description": "Search query (required)"
      },
      "lang": {
       "type": "string",
       "description": "Lang (optional)"
      },
      "limit": {
       "type": "string",
       "description": "Max results (optional)"
      }
     }
    }
   },
   "additionalProperties": false
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/api-x402node-dev-011ff50b/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.x402node.dev](https://www.zero.xyz/host/api.x402node.dev/llms.txt)