mcsci-hub 2026.5.11.1

FastMCP server for academic paper search, metadata, PDFs, citations, and BibTeX

mcsci-hub

An MCP server that gives LLMs access to academic literature. Search papers, retrieve metadata, download PDFs, traverse citation graphs, and generate BibTeX -- all through a unified interface backed by four academic data sources.

Built with FastMCP.

search "CRISPR delivery" --> get_paper(doi) --> fetch_pdf(doi) --> [mcp-pdf] --> analyze

How It Works

mcsci-hub aggregates data from multiple academic APIs in parallel, merging results into a single coherent response:

Source	What it provides	Access
CrossRef	Authoritative metadata -- title, authors, journal, volume, pages	Free (polite pool)
OpenAlex	Abstracts, open access URLs, semantic search	Free (polite pool)
Semantic Scholar	Citation counts, influential citations, fields of study, BibTeX	Free (optional API key)
Sci-Hub	Paywalled PDF access via mirror scraping	Fallback only

The strategy: always try open access first. Sci-Hub is a last resort. When any source fails, the others still return what they can (graceful degradation).

Tools

Tool	Description
search_papers(query, ...)	Keyword/topic search via OpenAlex with CrossRef fallback. Filters by year range and open access status.
get_paper(doi)	Full metadata from all sources, merged and cached. Returns title, authors, abstract, citation counts, fields of study, OA status.
fetch_pdf(doi)	Downloads the PDF: tries OA URL first, then Sci-Hub. Saves locally and hints to use mcp-pdf for parsing.
get_citations(doi, max_results)	Forward citations -- papers that cite this one. Includes Semantic Scholar's "influential" flag.
get_references(doi, max_results)	Backward references -- papers this one cites. Traces intellectual lineage.
get_bibtex(doi)	BibTeX entry from Semantic Scholar, or constructed from CrossRef metadata as fallback.

Resources

URI	Description
scihub://mirrors	Configured mirror domains and count
scihub://config	Full server configuration (cache, timeouts, PDF directory, API key status)
doi://{prefix}/{suffix}	Dynamic paper metadata lookup by DOI (e.g. doi://10.1038/nature12373)

Prompts

Prompt	Description
literature_review(topic, depth)	Guided workflow: search, detail top papers, traverse citations, synthesize. depth='deep' adds PDF analysis via mcp-pdf.
paper_deep_dive(doi)	Single paper analysis: metadata, PDF, full-text parsing, citation context.
extract_findings(doi)	Focused data extraction from a paper's PDF -- tables, results, conclusions.

Composability with mcp-pdf

fetch_pdf saves PDFs locally and returns the file path. Tool responses and prompts guide the calling LLM to use mcp-pdf for full-text extraction, creating the pipeline:

search --> fetch --> parse --> analyze

Install mcp-pdf alongside mcsci-hub to unlock the full workflow.

Installation

Requires Python 3.11+.

# Clone and install
git clone [e-mail]:MCP/mcsci-hub.git
cd mcsci-hub
uv sync

# Copy and edit environment config
cp .env.example .env

Add to Claude Code

# Local development
claude mcp add mcsci-hub -- uv run --directory /path/to/mcsci-hub mcsci-hub

# From PyPI (once published)
claude mcp add mcsci-hub -- uvx mcsci-hub

Run standalone (stdio transport)

uv run mcsci-hub

Configuration

All settings are managed via environment variables (loaded from .env by pydantic-settings).

Variable	Default	Description
SCIHUB_MIRRORS	sci-hub.se,sci-hub.st,sci-hub.ru	Comma-separated mirror domains, tried in order
CROSSREF_MAILTO	(empty)	Email for CrossRef polite pool (higher rate limits)
OPENALEX_MAILTO	(empty)	Email for OpenAlex polite pool
S2_API_KEY	(empty)	Optional Semantic Scholar API key for higher rate limits
CACHE_MAX_SIZE	1000	Maximum entries in the TTL cache
CACHE_TTL	3600	Cache entry lifetime in seconds
HTTP_TIMEOUT	30	Request timeout in seconds
PDF_SAVE_DIR	/tmp/mcsci-hub-pdfs	Directory where downloaded PDFs are saved

See .env.example for a ready-to-use template.

Data Source Strategy

Each field in the aggregated response has a primary and fallback source:

Field	Primary	Fallback	Notes
Title, Authors	CrossRef	OpenAlex, S2	CrossRef is the authoritative registry
Abstract	OpenAlex	S2	Decoded from inverted index format
Citation count	S2	OpenAlex	S2 distinguishes influential citations
Open Access URL	OpenAlex	S2	OpenAlex integrates Unpaywall data
Paywalled PDF	Sci-Hub	--	Mirror scraping, fallback only
BibTeX	S2	Constructed from CrossRef	S2 has citationStyles.bibtex
Fields of study	S2	--	Better classification taxonomy

All sources are queried in parallel via asyncio.gather with return_exceptions=True -- a slow or failing source never blocks the others.

Project Structure

src/mcsci_hub/
  server.py                  # FastMCP app, lifespan, resources, prompts
  config.py                  # pydantic-settings env config
  cache.py                   # TTL-aware LRU cache
  models.py                  # Pydantic response models
  clients/
    crossref.py              # CrossRef API (polite pool, rate limited)
    openalex.py              # OpenAlex API (abstracts, OA URLs)
    semantic_scholar.py      # S2 API (citations, BibTeX)
    scihub.py                # Sci-Hub scraper (mirror rotation, retry)
  tools/
    search.py                # search_papers
    paper.py                 # get_paper + aggregate_paper()
    pdf.py                   # fetch_pdf
    citations.py             # get_citations, get_references
    bibtex.py                # get_bibtex

Development

# Install with dev dependencies
uv sync

# Run tests (55 tests, all mocked with respx + FastMCP in-process transport)
uv run pytest -v

# Run tests with coverage
uv run pytest -v --cov=mcsci_hub

# Lint
uv run ruff check src/ tests/

License

MIT