CockroachDB MCP Server: Real-Time Mirroring & Zero-Downtime Resilience

CockroachDB MCP Server

This MCP server connects to a CockroachDB instance, exposing database and table schemas as resources, running SQL queries as tools, and providing prompts for query analysis.

Features

Resources

• postgres://{host}/databases/{database} - Get information about a specific database
• postgres://{host}/databases/{database}/tables/{table}/schema - Get the schema for a specific table
• postgres://{host}/cluster-metadata/{resource} - Get cluster metadata (requires auth token)
  • Currently supports: nodes - Information about cluster nodes

Tools

• query - Execute a SQL query with options for execution plan analysis

Installation

1. Clone this repository

2. Install dependencies:

   pnpm install

3. Build the project:

   npx tsc

Note: You must build the project with tsc before using the MCP server locally.

Configuration

The server requires a database URL as a command-line argument and optionally accepts an auth token for accessing admin UI endpoints:

node dist/server.js postgres://user:password@host:port/database [auth_token]

The auth token is required for accessing cluster metadata resources.

Using with Claude for Desktop

1. Open your Claude for Desktop App configuration:

* macOS: `~/Library/Application Support/Claude/claude_desktop_config.json`
* Windows: `%APPDATA%\Claude\claude_desktop_config.json`

2. Add your server configuration:

{
  "mcpServers": {
    "cockroachdb": {
      "command": "node",
      "args": [
        "/path/to/cockroachdb-mcp-server/dist/server.js", 
        "postgres://user:password@host:port/database",
        "your_auth_token"
      ]
    }
  }
}

3. Restart Claude for Desktop

Using with Cline

1. Open your Cline configuration file from the extension settings under "MCP Servers". Select "Configure MCP Servers".

2. Add your server configuration:

{
  "mcpServers": {
    "crdb": {
      "command": "node",
      "args": [
        "/path/to/cockroachdb-mcp-server/dist/server.js",
        "postgres://[[email protected]](/cdn-cgi/l/email-protection):26257/testdb",
        "your_auth_token"
      ]
    }
  }
}

3. Restart Cline or start a new session

Example Queries

Here are some example queries you can ask Claude:

1. "What databases are available in my CockroachDB instance?"
2. "Can you show me the schema for the 'users' table in the 'testdb' database?"
3. "Run this query on my database: SELECT * FROM users LIMIT 10"
4. "Debug this query and suggest improvements: SELECT * FROM orders WHERE customer_id = 123"
5. "Show me information about all nodes in my CockroachDB cluster"

Security Considerations

• Be careful when configuring database access. Consider using a read-only user for the connection if you only need to query data.
• The auth token is used to access the CockroachDB admin UI API. Make sure to keep this token secure.

Troubleshooting

• If you encounter connection issues, verify your database credentials and ensure the CockroachDB instance is accessible from your machine.
• For SQL errors, check the server logs for detailed error messages.
• If Claude can't see the server, verify the configuration file is properly formatted and the path to the server.js file is correct.
• For cluster metadata resources, ensure you've provided a valid auth token and that the admin UI is accessible on port 8080.