canonical: https://jentic.com/apis/api.crossref.org/crossref # Crossref REST API Jentic publishes the only available OpenAPI specification for Crossref REST API, keeping it validated and agent-ready. The Crossref REST API provides open access to scholarly metadata for millions of publications registered with Crossref. It searches and retrieves works by DOI, and it browses funders, members, journals, work types, licenses, and prefixes, each with their associated works. Every operation is a read, so an agent can look up citations, funding, and publication metadata without any write access. ## For AI agents Search and retrieve scholarly metadata by DOI and browse funders, members, journals, types, licenses, and prefixes from Crossref's open citation database. ## Scope Read-only scholarly metadata from Crossref. Does not register DOIs, deposit metadata, or provide full-text article content. ## Capabilities - Search scholarly works and retrieve a work by DOI - Browse funders and the works they funded - Browse members and the works they registered - Look up journals by ISSN and their works - List work types and licenses - Look up works by DOI prefix ## Use cases ### Citation Metadata Lookup A research agent resolves a DOI to full citation metadata for a reference list. It retrieves the work by DOI and reads the title, authors, and publication details. Through Jentic the agent finds the work operation and calls it directly with the DOI. Example prompt: Retrieve a work by its DOI and return its citation metadata ### Literature Search A discovery agent searches Crossref for works matching a query and filters the results. It queries the works endpoint with search terms and reads back the matching records. This backs a literature review without scraping publisher sites. Example prompt: Search works for a query and return the matching publications with metadata ### Funding Analysis An agent maps research output to funders to analyze funding impact. It browses funders and retrieves the works associated with a funder. This lets an analysis tool group publications by funding source. Example prompt: Look up a funder and retrieve the works it funded for analysis ### Journal and License Enrichment A repository agent enriches records with journal and license information from Crossref. It looks up a journal by ISSN and reads license terms for works. This appends authoritative source and reuse metadata to internal records. Example prompt: Look up a journal by ISSN and read the license terms for its works ## Key endpoints | Method | Path | Description | | --- | --- | --- | | GET | `/works` | Search scholarly works | | GET | `/works/{doi}` | Get a work by DOI | | GET | `/funders` | List funders | | GET | `/members` | List members | | GET | `/journals` | List journals | | GET | `/journals/{issn}` | Get a journal by ISSN | | GET | `/types` | List work types | ## Key resources - **Works** — Scholarly publications searchable and retrievable by DOI - **Funders** — Research funders and the works they funded - **Members** — Crossref members and the works they registered - **Journals** — Journals by ISSN and their works - **Types and licenses** — Work types, licenses, and DOI prefixes ## Why Jentic - **Setup:** Wiring Crossref by hand means constructing query requests against api.crossref.org and parsing its responses yourself. Through Jentic you install once, import Crossref from the API Directory, and your agent calls it. - **Permission scoping:** Crossref is read-only, so a rule limits your agent to the operations it needs, such as searching works. You choose which operations it may call, so funder, journal, or member queries are included only when you add them. - **Credential handling:** Crossref is a public API and needs no credentials, so there is nothing for Jentic to hold or inject. Your agent reaches it directly through your self-hosted Jentic One instance. - **Discovery method:** Agents search Jentic by intent such as 'search scholarly works' or 'get a work by DOI', and Jentic returns the matching Crossref operation with its parameters so the agent calls the right endpoint without browsing the reference docs. ## Related APIs - **OpenAlex** — OpenAlex is an open catalog of scholarly works, authors, and institutions, a broader alternative to Crossref. - **DataCite REST API** — DataCite registers DOIs for research datasets and outputs, an alternative focused on data rather than articles. - **CORE** — CORE aggregates open access research papers and full text, an alternative for discovering readable content. - **NCBI Datasets API** — NCBI Datasets provides biomedical and genomic data; pair it with Crossref to link publications to underlying data. ## FAQ ### Why is there no official OpenAPI spec for Crossref REST API? Crossref does not publish an OpenAPI specification for its REST API. Jentic generates and maintains this spec so that AI agents and developers can call the Crossref REST API via structured tooling. It is validated against the live API and kept up to date. To run it on your own infrastructure, install Jentic One from its GitHub repo. ### Does the Crossref REST API require authentication? No. The Crossref REST API is public and requires no authentication or API key, so an agent can read scholarly metadata directly. Providing a contact address places you in Crossref's polite pool for more reliable service, but no credential is needed to call it. ### How do I resolve a DOI with the Crossref REST API? The Crossref REST API retrieves a work by its DOI and returns full citation metadata such as title, authors, and publication details. An agent can pass a DOI to the work operation and read back the structured record for a reference list. ### What are the rate limits for the Crossref REST API? Crossref does not fix rate limits in the OpenAPI spec and adjusts service by traffic, favoring the polite pool. Check the Crossref documentation at https://www.crossref.org/documentation/retrieve-metadata/rest-api for current guidance, and back off when you receive a 429 response. ### How do I search scholarly works through Jentic? Search Jentic for 'search scholarly works', import Crossref from the API Directory, and your agent gets the works operation with its query parameters so it can call it directly and read back the matching publications. ### Can I limit what my agent is allowed to do with the Crossref REST API? Yes. The API is read-only, so you write a rule that allows the agent only the operations it needs, such as searching works, leaving funder, journal, or member queries out unless you add them. Because Jentic One is self-hosted, those rules and the audit log of every call stay on your own infrastructure. ### Is there a Crossref REST API MCP server? You do not need an MCP server to give your agent the Crossref REST API. Jentic connects it directly from the API Directory: import it and your agent can search works and browse funders and journals. That also keeps your agent's context free of an extra server's tool definitions.