OMOPHub MCP Server
Medical vocabularies for AI agents.
Search, map, and navigate 11M+ OMOP concepts: SNOMED CT, ICD-10, RxNorm, LOINC, and more. Directly from Claude, Cursor, VS Code, or any MCP-compatible client.
Quick Start ยท
Tools ยท
Examples ยท
Docs ยท
Website
Why OMOPHub MCP?
Working with medical vocabularies today means downloading multi-gigabyte CSV files, loading them into a local database, and writing SQL to find what you need. Every time.
OMOPHub MCP Server gives your AI assistant instant access to the entire OHDSI ATHENA vocabulary. No database setup, no CSV wrangling, no context switching. Just ask.
You: "Map ICD-10 code E11.9 to SNOMED"
Claude: Found it - E11.9 (Type 2 diabetes mellitus without complications)
maps to SNOMED concept 201826 (Type 2 diabetes mellitus)
via standard 'Maps to' relationship.
Use cases:
- Concept lookup - Find OMOP concept IDs for clinical terms in seconds
- Cross-vocabulary mapping - Map between ICD-10, SNOMED, RxNorm, LOINC, and 120+ vocabularies
- Hierarchy navigation - Explore ancestors and descendants for phenotype definitions
- Concept set building - Let your AI agent assemble complete concept sets for cohort definitions
- Code validation - Verify medical codes and check their standard mappings
Quick Start
1. Get an API Key
Sign up at omophub.com โ create an API key in your dashboard.
2. Add to Your AI Client
Claude Desktop
Open Claude Desktop settings > "Developer" tab > "Edit Config". Add to claude_desktop_config.json:
{
"mcpServers": {
"omophub": {
"command": "npx",
"args": ["-y", "@omophub/omophub-mcp"],
"env": {
"OMOPHUB_API_KEY": "oh_your_key_here"
}
}
}
}
Claude Code
claude mcp add omophub -- npx -y @omophub/omophub-mcp
Cursor
Open the command palette and choose "Cursor Settings" > "MCP" > "Add new global MCP server". Add to .cursor/mcp.json:
{
"mcpServers": {
"omophub": {
"command": "npx",
"args": ["-y", "@omophub/omophub-mcp"],
"env": {
"OMOPHUB_API_KEY": "oh_your_key_here"
}
}
}
}
VS Code
Add to .vscode/mcp.json:
{
"servers": {
"omophub": {
"command": "npx",
"args": ["-y", "@omophub/omophub-mcp"],
"env": {
"OMOPHUB_API_KEY": "oh_your_key_here"
}
}
}
}
Streamable HTTP (Remote / Hosted)
Run the MCP server as an HTTP service that clients connect to via URL:
npx -y @omophub/omophub-mcp --transport=http --port=3100 --api-key=oh_your_key_here
Connect MCP clients to / or /mcp. Useful for centralized deployments where multiple AI agents share one server instance.
Hosted (mcp.omophub.com)
Connect directly to the OMOPHub-hosted MCP server - no installation required. Each client authenticates with their own API key via the Authorization header:
Claude Code:
claude mcp add omophub --transport http \
-H "Authorization: Bearer oh_your_key_here" \
https://mcp.omophub.com
VS Code (.vscode/mcp.json):
{
"servers": {
"omophub": {
"type": "http",
"url": "https://mcp.omophub.com",
"headers": { "Authorization": "Bearer oh_your_key_here" }
}
}
}
Cursor / Windsurf:
{
"mcpServers": {
"omophub": {
"url": "https://mcp.omophub.com",
"headers": { "Authorization": "Bearer oh_your_key_here" }
}
}
}
Note: Claude Desktop's Custom Connectors UI only supports OAuth and cannot send custom headers. Use the npx setup instead.
Docker
docker run -e OMOPHUB_API_KEY=oh_your_key_here -p 3100:3100 omophub/omophub-mcp
docker run -i -e OMOPHUB_API_KEY=oh_your_key_here omophub/omophub-mcp --transport=stdio
3. Start Asking
"What's the OMOP concept ID for type 2 diabetes?"
"Map ICD-10 code E11.9 to SNOMED"
"Show me all descendants of Diabetes mellitus in SNOMED"
| Tool | What it does |
|---|
search_concepts | Search for medical concepts by name or clinical term across all vocabularies |
get_concept | Get detailed info about a specific OMOP concept by concept_id |
get_concept_by_code | Look up a concept using a vocabulary-specific code (e.g., ICD-10 E11.9) |
map_concept | Map a concept to equivalent concepts in other vocabularies (paginated โ see note below) |
get_hierarchy | Navigate concept hierarchy - ancestors, descendants, or both |
list_vocabularies | List available medical vocabularies with statistics |
semantic_search | Search using natural language with neural embeddings (understands clinical meaning) |
find_similar_concepts | Find concepts similar to a reference concept, name, or description |
explore_concept | Get concept details, hierarchy, and cross-vocabulary mappings in one call |
fhir_resolve | Resolve a FHIR coded value (incl. administrative codes via the HL7 FHIR-to-OMOP IG ConceptMaps) to its OMOP standard concept and CDM target table |
fhir_resolve_codeable_concept | Resolve a FHIR CodeableConcept โ best match by OHDSI vocabulary preference, honoring userSelected |
Resources
| URI | Description |
|---|
omophub://vocabularies | Full vocabulary catalog with statistics |
omophub://vocabularies/{vocabulary_id} | Details for a specific vocabulary |
Prompts
| Prompt | Description |
|---|
phenotype-concept-set | Guided workflow to build a concept set for a clinical phenotype |
code-lookup | Look up and validate a medical code with mappings and hierarchy |
Example Prompts
Find a concept โ search_concepts
"Search for metformin in RxNorm"
Cross-vocabulary mapping โ map_concept
"I have SNOMED concept 201826 - what's the ICD-10 code?"
Build a concept set โ search_concepts โ get_hierarchy โ map_concept
"Help me build a concept set for Type 2 diabetes including all descendants"
Completeness matters here. map_concept returns one page at a time
(page_size 1-200, default 100). A widely-used drug ingredient can have well over
a thousand NDC mappings, so a single call is a sample, not the answer. Check
has_more in the response and keep incrementing page until it is false โ
otherwise the concept set looks complete while silently missing codes.
Use find_similar_concepts for exploration, not for this: it is ranked embedding
similarity, so it has no notion of set membership and cannot be exhaustive no
matter how large page_size is.
Validate a code โ get_concept_by_code โ map_concept
"Is ICD-10 code E11.9 valid? What does it map to in SNOMED?"
Semantic search โ semantic_search
"Find concepts related to 'heart attack'"
Explore a concept โ explore_concept
"Give me everything about SNOMED concept 201826"
FHIR-to-OMOP resolution โ fhir_resolve
"Resolve FHIR SNOMED code 44054006 to OMOP โ what table does it go in?"
CodeableConcept โ fhir_resolve_codeable_concept
"This CodeableConcept has both SNOMED 44054006 and ICD-10 E11.9 โ which should I use for OMOP?"
Find similar โ find_similar_concepts
"What concepts are similar to 'Type 2 diabetes mellitus'?"
Configuration
Environment Variables
| Variable | Required | Description |
|---|
OMOPHUB_API_KEY | โ
| Your OMOPHub API key |
OMOPHUB_BASE_URL | | Custom API base URL (default: https://api.omophub.com/v1) |
OMOPHUB_LOG_LEVEL | | debug ยท info ยท warn ยท error (default: info) |
OMOPHUB_ANALYTICS_OPTOUT | | Set to true to disable analytics headers |
OMOPHUB_USER_AGENT_SUFFIX | | Optional deployment identifier appended to omophub-mcp/<version> (default: none) |
MCP_TRANSPORT | | stdio (default) or http |
MCP_PORT | | HTTP server port (default: 3100, only used with http transport) |
HEALTH_PORT | | Port for standalone health endpoint in stdio mode (default: disabled) |
CLI Arguments
npx @omophub/omophub-mcp --api-key=oh_your_key --base-url=https://custom.api.com/v1
npx @omophub/omophub-mcp --transport=http --port=3100 --api-key=oh_your_key
npx @omophub/omophub-mcp --api-key=oh_your_key --health-port=8080
Health Endpoint (Docker / Kubernetes)
In HTTP mode, the health endpoint is available at /health on the same port as the MCP endpoint:
npx @omophub/omophub-mcp --transport=http --port=3100 --api-key=oh_your_key
curl http://localhost:3100/health
In stdio mode, use --health-port for a standalone health endpoint:
HEALTH_PORT=8080 OMOPHUB_API_KEY=oh_your_key npx @omophub/omophub-mcp
curl http://localhost:8080/health
The Docker image defaults to HTTP mode on port 3100 with health checks built in.
Development
git clone https://github.com/OMOPHub/omophub-mcp.git
cd omophub-mcp
npm install
npm run build
npm test
Run locally:
OMOPHUB_API_KEY=oh_your_key npx tsx src/index.ts
Troubleshooting
| Error | Solution |
|---|
API key required | Set OMOPHUB_API_KEY in your environment or MCP config |
Authentication failed | API key may be invalid or expired - generate a new one |
Rate limit exceeded | Automatic retries are built in. For higher limits, upgrade your plan |
| Tools not appearing | Restart your AI client, verify npx @omophub/omophub-mcp runs without errors, check config path |
Links
License
MIT - see LICENSE