# Sequential Thinking MCP Server - Streamable HTTP Implementation
An MCP server that provides a powerful sequential thinking tool for complex problem-solving through thoughts.
This server enables AI assistants to work through problems step-by-step, with the ability to revise, branch, and explore alternative approaches as understanding deepens.
## Features
- **Dynamic Thought Process**: Adjust the number of thoughts as you progress
- **Revision Capability**: Question and revise previous thoughts
- **Branching Logic**: Explore alternative approaches
- **Flexible Planning**: Add more thoughts even after reaching initial estimates
- **Context Preservation**: Maintain context across multiple thinking steps
## Getting Started
To get started with this server, clone the repository and install the necessary dependencies.
```bash
git clone https://github.com/camilovelezr/server-sequential-thinking.git
cd server-sequential-thinking
npm install
```
## Usage
### Streamable HTTP Transport
The server uses the modern Streamable HTTP transport protocol for communication. Start the server:
```bash
npm start
```
The server will start on `http://127.0.0.1:3000` by default. You can change the port using the `PORT` environment variable:
```bash
PORT=8080 npm start
```
### Endpoints
- **MCP Endpoint**: `POST/GET/DELETE http://127.0.0.1:3000/mcp` - Main MCP communication endpoint
- `POST` - Send messages to the server (initialize, tool calls, etc.)
- `GET` - Establish SSE stream for server-to-client notifications
- `DELETE` - Terminate session
- **Health Check**: `GET http://127.0.0.1:3000/health` - Check server status and active sessions
- **Test Interface**: `GET http://127.0.0.1:3000/` - Browser-based test interface
### Transport Features
The Streamable HTTP transport provides several advantages:
- **Session-Based State**: Manages state for each client session in memory. The core server is long-running and can be scaled with sticky sessions.
- **Flexible Streaming**: Server can upgrade any response to SSE for streaming
- **Infrastructure Compatible**: Works with standard HTTP middleware and proxies
- **Resumable Connections**: Support for connection resumption
- **Automatic Session Cleanup**: Inactive sessions and their associated data are automatically cleared after 1 hour to conserve resources.
### Security
The implementation includes security measures:
- Origin header validation to prevent DNS rebinding attacks
- Server binds only to localhost (127.0.0.1)
- CORS headers are properly configured
- Session IDs are cryptographically secure
- **Privacy by Design**: No sensitive tool inputs or outputs are logged to the console.
### Adding to Cursor
To use this server with Cursor, add the following to your Cursor configuration:
```json
{
"mcpServers": {
"sequential-thinking": {
"url": "http://localhost:3000/mcp"
},
}
}
```
### Running with Docker
You can also run the server in a containerized environment using Docker for easier deployment and isolation.
1. **Build the Docker image:**
```bash
docker build -t mcp-server-sequential-thinking .
```
2. **Run the Docker container:**
```bash
docker run -p 3000:3000 mcp-server-sequential-thinking
```
The server will be accessible at `http://127.0.0.1:3000`.
## Available Tool
### sequentialthinking
A detailed tool for dynamic and reflective problem-solving through thoughts.
**When to use:**
- Breaking down complex problems into steps
- Planning and design with room for revision
- Analysis that might need course correction
- Problems where the full scope might not be clear initially
- Multi-step solutions requiring context preservation
**Parameters:**
- `thought` (string, required): Your current thinking step
- `nextThoughtNeeded` (boolean, required): Whether another thought step is needed
- `thoughtNumber` (integer, required): Current thought number
- `totalThoughts` (integer, required): Estimated total thoughts needed
- `isRevision` (boolean, optional): Whether this revises previous thinking
- `revisesThought` (integer, optional): Which thought is being reconsidered
- `branchFromThought` (integer, optional): Branching point thought number
- `branchId` (string, optional): Branch identifier
- `needsMoreThoughts` (boolean, optional): If more thoughts are needed
## License
MIT
