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Crossref DOI metadata enrichment
Inspect the exact response envelope first. When you need current analysis for your own input, one successful x402 call costs $0.003 USDC on Base or Solana.
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Full response envelope
What you receive
Demonstration data only. The paid endpoint returns a fresh result and settlement receipt.
{
"request_id": "018f1f54-7f38-7ba2-8dc3-5f90272d9f1a",
"service": "research.crossref-doi-metadata",
"version": "1",
"data": {
"doi": "10.1038/s41586-021-03819-2",
"status": "matched",
"work": {
"doi": "10.1038/s41586-021-03819-2",
"title": "Example normalized DOI record",
"type": "journal-article",
"publishedDate": "2021-08-25",
"authors": [],
"publisher": "Springer Science and Business Media LLC",
"containerTitle": "Nature",
"subjects": [],
"language": "en",
"doiUrl": "https://doi.org/10.1038/s41586-021-03819-2",
"resourceUrl": "https://api.crossref.org/works/10.1038%2Fs41586-021-03819-2",
"referenceCount": 0,
"citedByCount": 0,
"issn": [],
"isbn": [],
"licenses": [],
"updates": []
},
"source": "https://api.crossref.org/works/10.1038%2Fs41586-021-03819-2",
"retrievedAt": "2026-08-20T12:00:00+00:00",
"documentation": "https://www.crossref.org/documentation/retrieve-metadata/rest-api/",
"metadataLicense": {
"name": "Open bibliographic metadata / Crossref-generated data CC0",
"url": "https://www.crossref.org/documentation/retrieve-metadata/",
"abstractsReturned": false
},
"limitations": [
"Demonstration metadata only; paid calls return the current DOI record.",
"Abstracts and full text are deliberately excluded."
]
},
"meta": {
"duration_ms": 42,
"cached": false,
"sources": [],
"warnings": [],
"next_actions": []
}
}Example request
Input JSON
{
"doi": "10.1038/s41586-021-03819-2"
}Delivery contract
One paid POST
Resolve one DOI into normalized open Crossref bibliographic, author, container, citation-count, license, identifier, and correction or retraction-link metadata without abstracts or full text.
POST /v1/research/crossref-doi-metadata
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