Semantic Scholar MCP Server

An MCP server that gives Claude access to Semantic Scholar's database of 200M+ academic papers. Search papers, explore citation graphs, and look up authors — directly from Claude. Wraps the official semanticscholar SDK with a process-wide rate limiter to prevent 429s under concurrent dispatch.

Tools

Related MCP server: Semantic Scholar MCP Server

Setup

Prerequisites

• Python 3.11+

• uv (recommended) or pip

• A Semantic Scholar API key (see below — strongly recommended)

Get an API key

Without a key, requests share a global anonymous rate-limit bucket and you will see frequent 429 Too Many Requests errors during normal use. Request a free key at semanticscholar.org/product/api — turnaround is usually a few days.

Once you have a key, set it as an environment variable:

export S2_API_KEY=your_key_here

For persistence across shells, add the line to ~/.zshenv (or your shell's equivalent).

Install

git clone https://github.com/xiuyechen/semantic-scholar-mcp.git
cd semantic-scholar-mcp
uv pip install -e .

Or with pip:

pip install -e .

Rate limiting and retries

The client wraps the official semanticscholar Python SDK and adds a process-wide async token bucket on top. Concurrent calls from the same process serialize through a 1.05s floor so the client cannot burst past the API's 1 req/sec limit, even when an LLM dispatches multiple tools in parallel. Transient 429s are retried with Retry-After-aware exponential backoff (up to 5 attempts). No tuning required.

Configure with Claude

Claude Code

claude mcp add semantic-scholar -- semantic-scholar-mcp

Or with an API key:

claude mcp add semantic-scholar -e S2_API_KEY=your_key -- semantic-scholar-mcp

Claude Desktop

Add to your claude_desktop_config.json:

{
  "mcpServers": {
    "semantic-scholar": {
      "command": "semantic-scholar-mcp",
      "env": {
        "S2_API_KEY": "your_key_here"
      }
    }
  }
}

Example Usage

Once configured, you can ask Claude things like:

• "Search for recent papers on protein structure prediction"

• "Find the paper with DOI 10.1038/s41586-021-03819-2 and summarize it"

• "What papers cite AlphaFold2? Show me the most influential ones"

• "Look up David Baker's publication record"

• "Find open-access papers on CRISPR gene editing from 2024"

API Reference

This server wraps the Semantic Scholar Academic Graph API. The API is free to use and covers:

• 200M+ papers from all major publishers

• 2.4B+ citation edges

• Author profiles with h-index and affiliation data

• Open access PDF links where available

• AI-generated TLDR summaries for many papers

License

MIT