Wikidata stores structured facts: every item has an id (Q42 is Douglas Adams) and statements keyed by property ids (P31 is instance of).
None for reading. Wikimedia asks automated clients to send a descriptive User-Agent.
Full reference: https://www.wikidata.org/wiki/Wikidata:REST_API
curl "https://www.wikidata.org/w/api.php?action=wbsearchentities&search=douglas%20adams&language=en&format=json&limit=2&origin=*"{
"searchinfo": {
"search": "douglas adams"
},
"search": [
{
"id": "Q42",
"title": "Q42",
"pageid": 138,
"concepturi": "http://www.wikidata.org/entity/Q42",
"repository": "wikidata",
"url": "//www.wikidata.org/wiki/Q42",
"display": {
"label": {
"value": "Douglas Adams",
"language": "en"
},
"description": {
"value": "British science fiction writer and humorist (1952–2001)",
"language": "en"
}
},
"label": "Douglas Adams",
"description": "British science fiction writer and humorist (1952–2001)",
"match": {
"type": "label",
"language": "en",
"text": "Douglas Adams"
}
},
{
"id": "Q28421831",
"title": "Q28421831",
"pageid": 30117550,
"concepturi": "http://www.wikidata.org/entity/Q28421831",
"repository": "wikidata",
"url": "//www.wikidata.org/wiki/Q28421831",
"display": {
"label": {
"value": "Douglas Adams",
"language": "en"
},
"description": {
"value": "American environmental engineer",
"language": "en"
}
},
"label": "Douglas Adams",
"description": "American environmental engineer",
"match": {
"type": "label",
"language": "en",
"text": "Douglas Adams"
}
}
],
"search-continue": 2,
"success": 1
}curl "https://www.wikidata.org/w/api.php?action=wbgetentities&ids=Q42&props=labels|descriptions&languages=en&format=json&origin=*"{
"entities": {
"Q42": {
"type": "item",
"id": "Q42",
"labels": {
"en": {
"language": "en",
"value": "Douglas Adams"
}
},
"descriptions": {
"en": {
"language": "en",
"value": "British science fiction writer and humorist (1952–2001)"
}
}
}
},
"success": 1
}