CMS Data.gov MCP Server

A Model Context Protocol (MCP) server that provides Claude and other MCP clients with direct access to CMS (Centers for Medicare & Medicaid Services) healthcare data from data.cms.gov.

Overview

This MCP server enables AI assistants to:

• Search and discover CMS healthcare datasets
• Query dataset records with filters and pagination
• Get dataset statistics and metadata
• Obtain CSV download links for large-scale analysis

Perfect for healthcare analytics workflows, especially when working with LEJR (Lower Extremity Joint Replacement) analyses, provider enrollment data, hospital quality metrics, and other CMS datasets.

Features

Five Core Tools

1. cms_search_datasets - Find datasets by keyword or theme
2. cms_get_dataset - Get detailed dataset information
3. cms_query_dataset - Query data with filters (up to 5000 rows)
4. cms_get_dataset_stats - Get row counts and column info
5. cms_get_csv_link - Get CSV download URL for Athena

Resource Templates

• cms://datasets - Browse all available CMS datasets
• cms://dataset/{id} - Access specific dataset metadata
• cms://csv/{id} - Get CSV download link

Installation

Prerequisites

• Node.js 18 or higher
• Claude Desktop or other MCP-compatible client

Quick Install

# Clone or navigate to the project directory
cd cms-datagov-mcp-server

# Install dependencies
npm install

# Build the TypeScript code
npm run build

# Link globally (for Claude Desktop)
npm link

Configure Claude Desktop

Edit your Claude Desktop configuration file:

macOS: ~/Library/Application Support/Claude/claude_desktop_config.json

Windows: %APPDATA%\Claude\claude_desktop_config.json

Linux: ~/.config/Claude/claude_desktop_config.json

Add this configuration:

{
  "mcpServers": {
    "cms-datagov": {
      "command": "cms-datagov-mcp-server",
      "args": [],
      "env": {}
    }
  }
}

Restart Claude Desktop to activate the server.

Usage

Search for Datasets

"Search CMS datasets for TEAM episode"

Returns a list of matching datasets with IDs, descriptions, and available formats.

Get Dataset Details

"Get details for dataset 9887a515-7552-4693-bf58-735c77af46d7"

Returns comprehensive metadata including API endpoints, CSV links, and column information.

Query Dataset Records

"Query dataset 9887a515-7552-4693-bf58-735c77af46d7 where organization_ccn=100007, return 100 rows"

Returns up to 5000 rows with optional filtering, sorting, and column selection.

Get Dataset Statistics

"Get statistics for dataset 9887a515-7552-4693-bf58-735c77af46d7"

Returns column names, types, and metadata about the dataset.

Get CSV Download Link

"Get CSV link for dataset 9887a515-7552-4693-bf58-735c77af46d7"

Returns direct download URL for creating Athena EXTERNAL TABLEs.

API Reference

cms_search_datasets

Search CMS datasets by keyword, theme, or title.

Parameters:

• query (optional): Search term for titles, descriptions, or keywords
• theme (optional): Filter by theme (e.g., 'Medicare', 'Medicaid')
• limit (optional): Maximum results to return (default: 10)

Returns: Array of matching datasets with metadata

cms_get_dataset

Get detailed information about a specific dataset.

Parameters:

• dataset_id (required): UUID of the dataset

Returns: Complete dataset metadata including API endpoint and CSV URL

cms_query_dataset

Query dataset records with filtering and pagination.

Parameters:

• dataset_id (required): UUID of the dataset
• filter (optional): Filter expression (e.g., [field]=value)
• columns (optional): Comma-separated column list
• sort (optional): Column to sort by (prefix with - for descending)
• offset (optional): Number of rows to skip (default: 0)
• size (optional): Number of rows to return (max 5000, default: 100)

Returns: JSON array of matching records

cms_get_dataset_stats

Get statistics about a dataset.

Parameters:

• dataset_id (required): UUID of the dataset

Returns: Column information and dataset metadata

cms_get_csv_link

Get direct CSV download URL.

Parameters:

• dataset_id (required): UUID of the dataset

Returns: CSV download URL with usage instructions

Integration with Athena

For large datasets or complex analysis:

1. Use cms_get_csv_link to get the download URL
2. Download CSV to your S3 bucket
3. Create an Athena EXTERNAL TABLE:

CREATE EXTERNAL TABLE cms_team_data (
  organization_ccn STRING,
  organization_name STRING,
  -- ... other columns
)
ROW FORMAT DELIMITED
FIELDS TERMINATED BY ','
STORED AS TEXTFILE
LOCATION 's3://your-bucket/cms-data/'
TBLPROPERTIES ('skip.header.line.count'='1');

4. Run complex SQL queries in Athena

Troubleshooting

Server Not Appearing in Claude Desktop

1. Verify the server is linked: npm list -g @clarify/cms-datagov-mcp-server
2. Check configuration file syntax (valid JSON)
3. Restart Claude Desktop completely
4. Check Claude Desktop logs for errors

API Errors

• 404 Not Found: Invalid dataset ID
• Timeout: Dataset too large, use CSV download instead
• Rate Limit: Wait a moment and retry

Build Errors

# Clean and rebuild
rm -rf build node_modules
npm install
npm run build

CMS API Details

• Base URL: https://data.cms.gov/data-api/v1
• Catalog: https://data.cms.gov/data.json
• Max Rows: 5000 per request
• No Authentication: Public data, no API key required

When to Use MCP vs Athena

Use MCP for:

• Dataset discovery and exploration
• Quick lookups (< 1000 rows)
• Data validation
• Getting CSV links

Use Athena for:

• Large datasets (> 5000 rows)
• Complex joins and aggregations
• GROUP BY operations
• Repeated analysis

Development

Build

npm run build

Watch Mode

npm run watch

Testing

node test-validation.mjs

License

MIT License - See LICENSE file for details

Support

For CMS API questions: OEDAUserResearch@cms.hhs.gov

For MCP protocol documentation: https://modelcontextprotocol.io/

Related Resources

• CMS API Documentation
• CMS API Guide PDF
• Model Context Protocol
• Claude Desktop