RxJS

You run the RxJS MCP Server to execute, debug, and visualize RxJS streams from supported MCP clients. This server lets you run RxJS code locally, inspect emissions with timing details, analyze operator chains, detect memory leaks, and apply practical RxJS patterns across frameworks and use cases.

How to use

Connect to the server from an MCP client to run RxJS code, view emission timelines, and explore marble diagrams. You can execute streams, inspect emitted values with timestamps, and access utility tools that analyze operators, detect memory leaks, and suggest production-ready patterns. Use the client’s standard MCP workflow to send code, receive results, and review recommendations in real time.

How to install

Prerequisites: Node.js and npm must be installed on your system. Ensure you have a working network connection if you plan to run MCP clients remotely.

Install the MCP server package globally so you can invoke it from any project or client.

# Install the MCP server globally
npm install -g @shuji-bonji/rxjs-mcp

# Or use with npx
npx @shuji-bonji/rxjs-mcp

Configuration and running the server locally

Configure a local MCP client to connect to the RxJS MCP Server. The standard approach is to run the MCP server via a CLI command so clients can invoke it as a stdio-based server.

{
  "mcpServers": {
    "rxjs": {
      "command": "npx",
      "args": ["@shuji-bonji/rxjs-mcp"]
    }
  }
}

Using common MCP configurations

You can configure the server in multiple environments to integrate with your tools. Here are representative examples used by the MCP client ecosystems.

## Claude Desktop
{
  "mcpServers": {
    "rxjs": {
      "command": "npx",
      "args": ["@shuji-bonji/rxjs-mcp"]
    }
  }
}

## VS Code with Continue/Copilot
{
  "mcpServers": {
    "rxjs": {
      "command": "npx",
      "args": ["@shuji-bonji/rxjs-mcp"]
    }
  }
}

## Cursor
{
  "mcpServers": {
    "rxjs": {
      "command": "npx",
      "args": ["@shuji-bonji/rxjs-mcp"]
    }
  }
}

Security considerations

The server executes user-provided RxJS snippets in a controlled environment to prevent main process pollution and unauthorized access to system resources. Execution is constrained by timeouts and sandboxed contexts to minimize risk.

Examples of available capabilities

You gain access to a suite of tools that execute streams, generate visualizations, analyze operators, detect leaks, and suggest patterns. Practical tasks include running a simple interval-based stream, generating marble diagrams, and applying production-ready patterns to common use cases.

Troubleshooting tips

If the server does not respond, verify that the MCP client is configured to connect to the correct stdio command. Check that Node.js and npm versions are compatible with the MCP server, and ensure that the command used to start the server matches the configuration snippet shown above.

Notes on architecture and flow

The RxJS MCP Server exposes tools for execution, marble diagram generation, operator analysis, memory leak detection, and pattern suggestions. It sits between your AI assistant or client and the actual RxJS runtime, handling code execution in isolation and returning structured results that you can inspect in your client.

Development and testing

If you are developing or contributing, install dependencies, build the project, and run tests locally. Use dedicated commands for unit tests and MCP integration tests to validate behavior across environments.

Available tools

execute_stream

Execute RxJS code and capture stream emissions with timeline, including emitted values and timing information.

generate_marble

Create ASCII marble diagrams from timed events to visualize stream behavior over time.

analyze_operators

Analyze operator chains for performance and best practices, identifying bottlenecks and suggesting improvements.

detect_memory_leak

Detect potential memory leaks and missing cleanups, with guidance on proper unsubscribe patterns.

suggest_pattern

Provide production-ready RxJS patterns for common use cases like retry, typeahead, and state management.