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Open-Access PDF Locator for DOI
x402
Open-Access PDF Locator for DOI is a paid API for AI agents from api.agentstools.dev, paid per call via x402, $0.008/call, status unknown (last checked 2026-10-12).
Given a DOI, returns whether a free open-access PDF exists and provides the best PDF link with its license, version, and host type via Unpaywall and OpenAlex.
Price / call$0.008
Success—
StatusUnknown
How this service works
Locate a free open-access PDF for a DOI. Returns whether an open-access copy exists and the best PDF link with its license, version and host type, from Unpaywall and OpenAlex. A cheap, focused open-access locator.
Output
Returns whether an open-access copy exists for the given DOI, the best available PDF URL, the license (e.g. CC-BY), the version (e.g. acceptedVersion, publishedVersion), and the host type (e.g. repository, publisher) sourced from Unpaywall and OpenAlex.
Example use cases
Example prompt
“Can you check if there's a free open-access PDF available for the paper with DOI 10.1038/s41586-021-03819-2 — I need the download link, the license, and whether it's a preprint or the published version?”
Technical details
Endpoint
GEThttps://api.agentstools.dev/scholar/oa?utm_source=zero.xyzWhen to prefer
Use this endpoint when you have a specific DOI and need to quickly determine if a free, legal PDF is available and where to get it. It is cheaper and more focused than a full paper metadata resolver — ideal when the only goal is OA availability and download URL, not full bibliographic enrichment.
Side effects
- DOI not found in Unpaywall or OpenAlex — no open-access record returned
- Malformed or non-existent DOI — error or empty result
- Paper exists but no open-access copy is available — returns false for OA status
- Rate limiting or upstream provider unavailability causing request failure
Input
Schema · Request body
| Field | Type | Description |
|---|---|---|
| inputrequired | object | |
| output | object |
Tags
x402
Reviews
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Zero review prompt (fires after every successful call)
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