KurrentDB MCP Server

This is a simple MCP server to help you explore data and prototype projections faster on top of KurrentDB.

Recommended Usage

• Claude Desktop
• Sequential Thinking MCP for complex tasks

Installation

KurrentDB Setup

You need to enable --run-projections=all and --start-standard-projections on KurrentDB The $streams stream is used to look for available streams.

Python Dependencies

Ensure the packages in requirements.txt are installed using pip

OS Dependencies

Ensure the vu package is installed on your machine where you will be running the MCP Server

For Mac: brew install uv

MCP Client Setup (VS Code)

{
    "servers": {
      "KurrentDB": {
        "type": "stdio",
        "command": "uv",
            "args": [
                "--directory",
                "path to mcp-server folder",
                "run",
                "server.py"
            ],
	    "env": {
             "KURRENTDB_CONNECTION_STRING": "insert kurrentdb connection here"
        }
      }
    }
  }

This configuration file should work in VS Code (.vscode/mcp.json).

MCP Client Setup (Claude)

{
    "mcpServers": {
      "KurrentDB": {
        "type": "stdio",
        "command": "uv",
            "args": [
                "--directory",
                "path to mcp-server folder",
                "run",
                "server.py"
            ],
	    "env": {
             "KURRENTDB_CONNECTION_STRING": "insert kurrentdb connection here"
        }
      }
    }
  }

This configuration file should work in Claude Desktop (https://modelcontextprotocol.io/quickstart/user).

MCP Client Setup (Cursor or Windsurf)

{
  "mcpServers": {
    "kurrentdb": {
      "command": "python",
      "args": ["path to mcp-server folder\\server.py"],
      "env": {
             "KURRENTDB_CONNECTION_STRING": "insert kurrentdb connection here" 
         }
    }
  }
}

This configuration file should work in Cursor (.cursor\mcp.json) and Windsurf (.codeium\windsurf\mcp_config.json).

Overview

This MCP server is designed to make stream data available to the MCP client. It provides a simple interface for querying and retrieving stream data. It can also create, test and debug projections.

Access control is done using the KurrentDB connection string provided at configuration time as an environment variable.

Components

Tools

The servers exposes 8 tool calls:

1. read_stream
2. list_streams
3. build_projection
4. create_projection
5. update_projection
6. test_projection
7. write_events_to_stream
8. get_projections_status

Configuration

• ConnectionString: This is a KurrentDB connection string which includes user credentials. Depending on the client being used, this can come from environment variable or a JSON Configuration file like in Claude Desktop’s case.

Usage Documentation

Available Tools

1. Stream Operations

read_stream