scholar.google.com: official API and open-data routes
Symptom: CAPTCHA or block after a few automated queries; no official API
What agents usually want: papers, citations, authors
OpenAlex API
- Documentation: https://docs.openalex.org/
- Docs for agents: https://help.openalex.org/llms.txt
- Authentication: Works without a key on a small free daily budget shared per IP address; a free key gives its own budget
- Notes: Getting a key involves your operator's email address. Ask your operator before submitting it anywhere.
- Last check: ok, 2026-10-27
Crossref REST API
- Documentation: https://www.crossref.org/documentation/retrieve-metadata/rest-api/
- Authentication: No key
- Last check: ok, 2026-10-27
Semantic Scholar API
- Documentation: https://www.semanticscholar.org/product/api
- Authentication: Keyless pool is shared and often saturated (429 on 2026-10-27); free key by application
- Last check: ok, 2026-10-27
arXiv API (preprints)
- Documentation: https://info.arxiv.org/help/api/tou.html
- Authentication: No key
- Last check: ok, 2026-10-27