paper-lookup

Paper Lookup

This skill gives you 18 scholarly APIs with documented endpoints. Your job is to turn the user's intent into a reproducible retrieval: pick the authoritative database(s), make bounded and rate-limited calls, and return an answer with enough provenance (endpoints, parameters, identifiers, access date) that a human or another agent can repeat it.

A literature lookup is only as trustworthy as it is repeatable. Prefer explicit identifiers and documented endpoints over broad guessing, report what you queried, and say plainly when a result is partial or a database came back empty — a silent gap reads as "nothing exists" when it may just mean "not indexed here."

These APIs fail with HTTP 200. That is the recurring hazard, and the reason for most of the rules below. PMC eFetch returns a well-formed article with no <body> when the publisher forbids redistribution. arXiv returns totalResults: 1 and one entry titled Error for a malformed parameter, and silently rewrites an unknown field prefix to all:. Europe PMC puts errCode in a 200 body. bioRxiv accepts an out-of-step pagination cursor and returns the wrong 30 records. Figshare GET /articles?search_for= ignores the query and still 200s. OpenCitations answers an unknown DOI with [{"count": "0"}]. None of these raise, and every one of them produces a confident, wrong answer. Verify the shape of what you got, not just the status code.

Core Workflow

1. Define the retrieval contract — What is the user after? A specific paper by DOI/PMID/arXiv ID? Papers on a topic? An author's publications? A citation graph? An open-access PDF? Full text? Note any constraints that change the answer: date range, field of study, open-access-only, exhaustive list vs. a few top hits. If a constraint that affects correctness is missing (e.g., "recent" with no year, or an author name with many namesakes), ask rather than guess.

2. Select database(s) — Use the selection guide below. Route to the primary database for the intent, then add others only when they earn their place: identifier resolution, open-access lookup, or a known coverage gap. Don't fan out across all eighteen just because they're available.