Ontology Lookup Service (OLS) MCP Server

Searches and resolves terms across biomedical ontologies through EMBL-EBI’s Ontology Lookup Service via a community MCP server.

Type	MCP server
Supplier	seandavi
Availability	Beta — community OSS
Pricing	Free / OSS
Capabilities	Read-only
Verified	works · 2026-07-20
Security	caution · 2026-07-20 — no LICENSE on GitHub, single-maintainer, stale

How to install

• Claude Code / Desktop — MCP server (seandavi/ols-mcp-server, OSS):

  git clone https://github.com/seandavi/ols-mcp-server
  cd ols-mcp-server
  uv run ols-mcp-server
  

• Claude Science — also available as the Genes & Ontologies featured connector (Anthropic-hosted).
• Public API — ebi.ac.uk/ols4/api.

What it does

Search across hundreds of ontologies (e.g., GO, EFO, MONDO, HP, ChEBI, Uberon), resolve terms and CURIEs, and traverse term hierarchies via the OLS4 API.

Primary use cases: Ontology term search, CURIE resolution, disease/phenotype ontology mapping

Notes

Claude Science: Offered inside Anthropic’s Claude Science via the Genes & Ontologies featured connector. Its inclusion there is an independent signal of quality and trustworthiness for life-science research.

Wraps the EMBL-EBI OLS4 API. Confirm the exact entry point in the repo README.

Sources

• seandavi/ols-mcp-server
• EMBL-EBI OLS
• Anthropic — Claude Science: Connectors and skills

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