# clinicaltrialsgov-mcp-server Connects AI assistants to the ClinicalTrials.gov registry to query studies, pull outcome data, and pre-screen trials for patient profiles. No API key needed. - MCP server · `type=mcp` · Claude Code, Codex, Cursor, GitHub Copilot, Windsurf (Devin Desktop), Cline, Zed, Gemini CLI · ★ 98 - Author: cyanheads - License: Apache-2.0 · policy=link-only · description only; the file stays with the author - Source: https://github.com/cyanheads/clinicaltrialsgov-mcp-server - Updated: 2026-10-23 - HTML: https://affpapa.org/en/nevibecode/mcp/clinicaltrialsgov-mcp-server ## What it does The server provides access to clinical study records using seven tools and the `clinicaltrials://{nctId}` resource. It runs free-text and field queries covering conditions, sponsors, locations, or trial phases, and retrieves posted outcome data for completed trials. While `clinicaltrials_find_eligible` filters recruiting studies by age, sex, and diagnosis, it skips inclusion and exclusion criteria analysis. Protocol criteria still require manual review. You can run it locally via `npx` over STDIO or attach directly to the hosted HTTP endpoint. ## Requirements - Needs: Node.js (commands run via npx) - Remote server: `https://clinicaltrials.caseyjhand.com/mcp` - Environment variables: `CT_API_BASE_URL`, `CT_REQUEST_TIMEOUT_MS`, `CT_MAX_PAGE_SIZE`, `MCP_LOG_LEVEL`, `MCP_TRANSPORT_TYPE`, `MCP_HTTP_HOST`, `MCP_HTTP_PORT`, `MCP_HTTP_ENDPOINT_PATH`, `MCP_AUTH_MODE` — keys and tokens: ask the human for the values, never commit them or put them in shared files. ## Install ### Claude Code (native platform) 1. **Platform CLI: remote server** ```bash claude mcp add --transport http clinicaltrialsgov-mcp-server https://clinicaltrials.caseyjhand.com/mcp ``` 2. **Platform CLI** ```bash claude mcp add --env CT_API_BASE_URL= --env CT_REQUEST_TIMEOUT_MS= --env CT_MAX_PAGE_SIZE= --env MCP_LOG_LEVEL= --env MCP_TRANSPORT_TYPE= --transport stdio clinicaltrialsgov-mcp-server -- npx -y clinicaltrialsgov-mcp-server ``` Replace <…> with your own values. 4 more environment variables are in the server README ### Codex 1. **Platform CLI: remote server** ```bash codex mcp add clinicaltrialsgov-mcp-server --url https://clinicaltrials.caseyjhand.com/mcp ``` 2. **Platform CLI** ```bash codex mcp add clinicaltrialsgov-mcp-server --env CT_API_BASE_URL= --env CT_REQUEST_TIMEOUT_MS= --env CT_MAX_PAGE_SIZE= --env MCP_LOG_LEVEL= --env MCP_TRANSPORT_TYPE= -- npx -y clinicaltrialsgov-mcp-server ``` Replace <…> with your own values. 4 more environment variables are in the server README ### Cursor **Config file** File `.cursor/mcp.json`: ```json { "mcpServers": { "clinicaltrialsgov-mcp-server": { "url": "https://clinicaltrials.caseyjhand.com/mcp" } } } ``` File `.cursor/mcp.json`: ```json { "mcpServers": { "clinicaltrialsgov-mcp-server": { "command": "npx", "args": [ "-y", "clinicaltrialsgov-mcp-server" ], "env": { "CT_API_BASE_URL": "", "CT_REQUEST_TIMEOUT_MS": "", "CT_MAX_PAGE_SIZE": "", "MCP_LOG_LEVEL": "", "MCP_TRANSPORT_TYPE": "" } } } } ``` Replace <…> with your own values. 4 more environment variables are in the server README ### GitHub Copilot **Config file** File `.vscode/mcp.json`: ```json { "servers": { "clinicaltrialsgov-mcp-server": { "type": "http", "url": "https://clinicaltrials.caseyjhand.com/mcp" } } } ``` File `.vscode/mcp.json`: ```json { "servers": { "clinicaltrialsgov-mcp-server": { "type": "stdio", "command": "npx", "args": [ "-y", "clinicaltrialsgov-mcp-server" ], "env": { "CT_API_BASE_URL": "", "CT_REQUEST_TIMEOUT_MS": "", "CT_MAX_PAGE_SIZE": "", "MCP_LOG_LEVEL": "", "MCP_TRANSPORT_TYPE": "" } } } } ``` Replace <…> with your own values. 4 more environment variables are in the server README ### Gemini CLI 1. **Platform CLI: remote server** ```bash gemini mcp add -t http clinicaltrialsgov-mcp-server https://clinicaltrials.caseyjhand.com/mcp ``` 2. **Platform CLI** ```bash gemini mcp add -e CT_API_BASE_URL= -e CT_REQUEST_TIMEOUT_MS= -e CT_MAX_PAGE_SIZE= -e MCP_LOG_LEVEL= -e MCP_TRANSPORT_TYPE= clinicaltrialsgov-mcp-server npx -y clinicaltrialsgov-mcp-server ``` Replace <…> with your own values. 4 more environment variables are in the server README ## When to use it - search active clinical trials by condition, sponsor, or location coordinates - retrieve full protocol records and reported study outcomes by NCT identifier - count matching trials quickly without downloading entire study records - screen candidate studies matching patient demographics and diagnoses ## Example prompts - Find recruiting phase 3 breast cancer studies within 50 miles of Boston - Get published outcome measures and adverse event summary for NCT04280705 - Count how many completed stroke trials have posted results ## Similar - [Zotero MCP](https://affpapa.org/en/nevibecode/mcp/zotero-mcp.md) — MCP server · ★ 5548 - [arxiv-mcp-server](https://affpapa.org/en/nevibecode/mcp/arxiv-mcp-server.md) — MCP server · ★ 3231 - [PaperBanana](https://affpapa.org/en/nevibecode/mcp/paperbanana.md) — MCP server · ★ 2417 - [MATLAB MCP Server](https://affpapa.org/en/nevibecode/mcp/matlab-mcp-server.md) — MCP server · ★ 1716 - [Hex Research](https://affpapa.org/en/nevibecode/mcp/hex-research.md) — MCP server · ★ 583 - [DocsAgent — Zotero, Obsidian & Apple Notes MCP Server](https://affpapa.org/en/nevibecode/mcp/docsagent-zotero-obsidian-apple-notes-mcp-server.md) — MCP server · ★ 578 --- NeVibeCode on affpapa.org. 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