checkRetraction

Looks up the live retraction status of an identifier against Crossref's update relationships and the Retraction Watch database. The route resolves any supported identifier to a DOI first, then checks it. Returns retraction / correction / expression-of-concern flags plus the notice records.

When to use

• A user asks "is this paper still valid?" or "has this been retracted?"
• An agent is about to cite a paper in a clinical, legal, or academic context where retraction-awareness matters.
• A reviewer wants to flag retracted references in a manuscript.

Inputs

• id (string, required) — one identifier per call: DOI, PMID, PMCID, arXiv ID, or ADS bibcode. Pass it verbatim (PMID: and similar prefixes are tolerated). Books/ISBNs have no DOI, so they return a "no DOI" result.

Outputs