paper-mcp

Remotely-callable MCP server for academic paper search, full-text retrieval & image→LaTeX, served at https://latex-tools.online/mcp.

Three corpora behind one normalized interface:

• arxiv (default) — search, metadata, and full-text (HTML / markdown / LaTeX source)
• semanticscholar (alias s2) — the full S2 API surface: citation graph, authors, recommendations, full-text snippets, bulk datasets
• openalex (alias oa) — 316M all-field works: citation graph, authors with h-index, institutions, topics, influence metrics

Plus a unified search_all that fuses all three corpora, and image→LaTeX OCR tools.

---

Tools (37)

Generic / source-agnostic (8)

Tool	Purpose
search_all(query, max_results=10, sources='arxiv,semanticscholar,openalex')	Unified search. Fans out to all three corpora concurrently, de-duplicates the same work (by DOI/title) and re-ranks with Reciprocal Rank Fusion. Each hit carries sources (who found it) + an ids map for follow-up calls. Prefer this for broad lookups.
search_papers(query, source='arxiv', max_results=10, sort_by='relevance')	Single-corpus search. arXiv query accepts plain text or field syntax (ti: au: cat:cs.CL abs: + AND/OR).
get_paper(paper_id, source='arxiv')	One paper's full record. S2 id accepts S2 id / DOI: / ARXIV: / CorpusId:.
search_by_author(author, source='arxiv')	Papers by author, newest first.
list_recent(category, source='arxiv')	Latest in a category (arXiv code or S2 field of study).
list_categories(source='arxiv')	Common category codes.
read_paper(paper_id, format='markdown')	FULL text (arXiv). markdown = body with formulas as $LaTeX$; html = raw LaTeXML page; latex = original manuscript .tex source.
list_paper_sources()	Available corpora.

read_paper fetch chain: arxiv.org/html/{id} → ar5iv fallback (markdown/html), or arxiv.org/e-print/{id} tarball main .tex (latex). Formulas are recovered from the LaTeXML alttext invariant.

Image → LaTeX (3)

Turn a formula or table image back into LaTeX (e.g. a figure cropped from a paper) without needing your own vision model. Backed by the co-located recognize service (PaddleOCR-VL / DeepSeek-OCR / texify).

Tool	Purpose
recognize_formula(image_url=... or image_base64=..., model='deepseek-ocr')	Formula image → LaTeX. image_url is downloaded server-side (with SSRF guards). Returns {latex, model, elapsed_ms}.
recognize_table(image_url=... or image_base64=..., model='deepseek-ocr')	Table image → LaTeX tabular.
list_ocr_models()	Available OCR models (deepseek-ocr, paddleocr-vl, texify).

OpenAlex (8)

• Works: get_openalex_work · get_openalex_citations · get_openalex_references · search_openalex_works (filters: year range, open-access, min-citations, institution)
• Authors/Institutions: search_openalex_authors · search_openalex_institutions
• Analytics: get_openalex_trends · list_openalex_topics

Semantic Scholar (18)

• Graph: get_paper_citations · get_paper_references · get_paper_authors
• Lookup: match_paper_title · autocomplete_papers
• Bulk: search_papers_bulk (≤1000, sortable, token paging) · get_papers_batch
• Authors: search_authors · get_author · get_author_papers · get_authors_batch
• Full-text: search_snippets (search inside paper body)
• Recommend: recommend_papers_for_paper · recommend_papers_from_examples
• Datasets: list_dataset_releases · get_dataset_release · get_dataset_download_links · get_dataset_diffs

---

Layout

paper_mcp/
  server.py            FastMCP server (tool registrations + instructions)
  models.py            normalized Paper model
  aggregate.py         cross-source fusion (dedup + Reciprocal Rank Fusion)
  sources/
    base.py            source registry (get_source / list_sources)
    arxiv.py           arXiv Atom API + read_paper (HTML/markdown/latex)
    semanticscholar.py Semantic Scholar full API surface
    openalex.py        OpenAlex REST API (works/authors/institutions/topics)
    recognize.py       image→LaTeX client over the co-located recognize service
pyproject.toml

Run locally

cd paper-mcp
python -m venv .venv && . .venv/bin/activate
pip install -e .
PAPER_MCP_PORT=9400 python -m paper_mcp.server
# MCP endpoint at http://127.0.0.1:9400/mcp (JSON-RPC; a plain GET returns 406)

Env

Var	Default	Notes
PAPER_MCP_HOST	127.0.0.1
PAPER_MCP_PORT	9400
PAPER_MCP_PATH	/mcp
SEMANTIC_SCHOLAR_API_KEY	—	optional; raises S2 rate limit. Set via /etc/paper-mcp.env in prod.

---

Deployment (latex-tools.online)

• Runs as paper-mcp.service on the latex-tools server, WorkingDirectory /opt/paper-mcp, port 9400.
• nginx reverse-proxies https://latex-tools.online/mcp → 127.0.0.1:9400/mcp.
• Secrets in /etc/paper-mcp.env (SEMANTIC_SCHOLAR_API_KEY).
• systemd unit + env are backed up under ../deploy/ in this repo.

Update flow

This repo is the source of truth. The server runs an independent copy under /opt/paper-mcp (not auto-synced):

# edit here → push → deploy
scp -r paper_mcp/* latex-tools:/opt/paper-mcp/paper_mcp/
ssh latex-tools 'systemctl restart paper-mcp'
ssh latex-tools 'curl -s -o /dev/null -w "%{http_code}\n" http://127.0.0.1:9400/mcp'  # 406 = healthy (needs JSON-RPC handshake)

Notes

• arXiv calls are politely rate-limited + retried (_USER_AGENT, backoff).
• read_paper covers ~80%+ of papers via official HTML; older scan-only papers may have no full text.
• Moved here from the docs repo on 2026-06-07; that copy is gone.