> ## Documentation Index
> Fetch the complete documentation index at: https://docs.omophub.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Hosted MCP Server for OMOP vocabularies

> Connect AI clients to the OMOPHub MCP Server hosted at mcp.omophub.com with no installation, giving agents instant access to OMOP vocabularies.

## What is Hosted MCP?

OMOPHub runs an MCP server for you at `mcp.omophub.com`. Connect your AI client directly - no npm install, no Docker, no infrastructure to manage. Just your API key and a URL.

All 9 tools are available: concept search, semantic search, hierarchy navigation, cross-vocabulary mapping, and more.

## Endpoint

| URL                       | Description           |
| :------------------------ | :-------------------- |
| `https://mcp.omophub.com` | MCP protocol endpoint |

## Client Compatibility

| Client              | Hosted MCP | How                                                                                                                                  |
| :------------------ | :--------: | :----------------------------------------------------------------------------------------------------------------------------------- |
| **Claude Code**     |     Yes    | Custom headers supported natively                                                                                                    |
| **VS Code**         |     Yes    | `headers` field in mcp.json                                                                                                          |
| **Cursor**          |     Yes    | `headers` field in MCP config                                                                                                        |
| **Windsurf**        |     Yes    | Same as Cursor                                                                                                                       |
| **Claude Desktop**  |   Use npx  | Custom Connectors UI only supports OAuth, not Bearer tokens. Use the [self-hosted npx setup](/ai/mcp-server#claude-desktop) instead. |
| **Claude.ai (web)** |   Use npx  | Same limitation as Claude Desktop.                                                                                                   |

## Quick Setup

You need two things: the endpoint URL and your API key (get one at [dashboard.omophub.com](https://dashboard.omophub.com)).

### Claude Code

```bash theme={null}
claude mcp add omophub --transport http \
  -H "Authorization: Bearer oh_your_key_here" \
  https://mcp.omophub.com
```

### VS Code

Add to `.vscode/mcp.json`:

```json theme={null}
{
  "servers": {
    "omophub": {
      "type": "http",
      "url": "https://mcp.omophub.com",
      "headers": {
        "Authorization": "Bearer oh_your_key_here"
      }
    }
  }
}
```

### Cursor

Add to your Cursor MCP configuration:

```json theme={null}
{
  "mcpServers": {
    "omophub": {
      "url": "https://mcp.omophub.com",
      "headers": {
        "Authorization": "Bearer oh_your_key_here"
      }
    }
  }
}
```

### Windsurf

Same configuration pattern as Cursor:

```json theme={null}
{
  "mcpServers": {
    "omophub": {
      "url": "https://mcp.omophub.com",
      "headers": {
        "Authorization": "Bearer oh_your_key_here"
      }
    }
  }
}
```

### Claude Desktop

Claude Desktop's Custom Connectors UI only supports OAuth authentication and cannot send custom Bearer tokens. Use the self-hosted npx approach instead - it works identically and requires no infrastructure:

```json theme={null}
{
  "mcpServers": {
    "omophub": {
      "command": "npx",
      "args": ["-y", "@omophub/omophub-mcp"],
      "env": {
        "OMOPHUB_API_KEY": "oh_your_key_here"
      }
    }
  }
}
```

## Verify Connection

```bash theme={null}
curl https://mcp.omophub.com/health
# {"status":"ok","version":"1.3.0"}
```

<Card title="Self-Hosted Installation" icon="terminal" href="/ai/mcp-server">
  Prefer to run the MCP server yourself? See the self-hosted installation guide.
</Card>

## Troubleshooting

| Issue                | Solution                                                   |
| :------------------- | :--------------------------------------------------------- |
| `Connection refused` | Verify the URL is `https://mcp.omophub.com` (not just `/`) |
| `401 Unauthorized`   | Check your API key is valid and prefixed with `oh_`        |