# Paper Lookup

> Use as a metadata and discovery fallback for papers, preprints, citations, DOIs, PMIDs, and open-access signals after local library routing is exhausted or when external paper discovery is explicitly needed.

- Skill: `hoanganhduc/paper-lookup` (Agent Skill, multi-file: 9 files)
- Install (CLI): `npx skillmds@latest add hoanganhduc/paper-lookup`
- Raw SKILL.md: https://api.skillmd.com/api/skills/hoanganhduc/paper-lookup/raw
- Safety review: pending
- Works with: Claude Code, Claude.ai, OpenAI Codex
- Category: Product & Planning
- Author: hoanganhduc (https://skillmd.com/u/hoanganhduc)
- Updated: 2026-09-17
- Page: https://skillmd.com/skills/hoanganhduc/paper-lookup

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# Paper Lookup

Use this skill for external literature discovery and metadata lookup.

## Important routing boundary

Do **not** replace the existing library-first workflow.

Keep this order:
- `zotero` first for paper/library retrieval
- `calibre` second for review tasks needing a local document
- `paper-lookup` for external metadata/discovery
- `getscipapers-requester` for actual external retrieval when needed

## Good use cases

- find papers on a topic
- resolve a DOI or PMID
- check whether a paper has an open-access location
- search major literature APIs before retrieval

## High-value references

- `references/pubmed.md`
- `references/pmc.md`
- `references/arxiv.md`
- `references/biorxiv.md`
- `references/crossref.md`
- `references/openalex.md`
- `references/semantic-scholar.md`
- `references/unpaywall.md`