Sequential Thinking MCP Server

🧠 Intelligent MCP Server for step-by-step analysis and solving complex problems using the powerful mcp-go library.

Supports multiple transport protocols:

• STDIO - For MCP clients (VS Code, Claude Desktop)
• SSE (Server-Sent Events) - For real-time web applications
• StreamableHTTP - For traditional web services and REST-like interactions

⚡ Quick Start

1. Building the project

# Clone repository
git clone https://github.com/ad/sequentialthinking.git
cd sequentialthinking

# Install dependencies
go mod tidy

# Local build using Go
go build -o sequentialthinking-server main.go

# Or using Make
make build-local

# Docker build
make build

2. Running the server

📡 For MCP clients (VS Code, Claude Desktop) - STDIO mode

./sequentialthinking-server -transport stdio
# Or using Make
make run-stdio

🌐 For real-time web applications - SSE mode

./sequentialthinking-server -transport sse
# Or with custom port
./sequentialthinking-server -transport sse -port 3000

🔗 For traditional web services - HTTP mode

./sequentialthinking-server -transport http
# Or with custom port
./sequentialthinking-server -transport http -port 9090

🐳 Using Docker

# Run in Docker (default STDIO mode)
make run
# Or manually
docker run --rm danielapatin/sequentialthinking:latest

# Run with HTTP mode on port 8080
docker run --rm -p 8080:8080 danielapatin/sequentialthinking:latest -transport http -port 8080

3. Testing

# Go unit tests
go test -v
# Or using Make
make test

# Test build
make build-local

# Test different transport modes
./sequentialthinking-server -transport stdio   # Test STDIO mode
./sequentialthinking-server -transport sse     # Test SSE mode on port 8080
./sequentialthinking-server -transport http    # Test HTTP mode on port 8080

🚀 Usage

Integration with VS Code

Usage with VS Code

For quick installation, click the installation button below...

Or add to ~/Library/Application Support/Code/User/settings.json:

{
  "mcp": {
    "servers": {
      "sequentialthinking": {
        "type": "stdio", 
        "command": "/absolute/path/to/sequentialthinking-server",
        "args": ["-transport", "stdio"]
      }
    }
  }
}

Or use Docker:

{
  "mcp": {
    "servers": {
      "sequentialthinking": {
        "type": "stdio",
        "command": "docker",
        "args": ["run", "--rm", "-i", "danielapatin/sequentialthinking:latest", "-transport", "stdio"]
      }
    }
  }
}

Integration with Claude Desktop

Add to claude_desktop_config.json:

{
  "mcpServers": {
    "sequentialthinking": {
      "command": "/absolute/path/to/sequentialthinking-server",
      "args": ["-transport", "stdio"],
    }
  }
}

Web Integration (SSE/HTTP modes)

For web applications, you can use SSE or HTTP transport:

// SSE Client Example
const eventSource = new EventSource('http://localhost:8080/sse');
eventSource.onmessage = function(event) {
    const data = JSON.parse(event.data);
    console.log('Received:', data);
};

// HTTP Client Example
fetch('http://localhost:8080/mcp', {
    method: 'POST',
    headers: {
        'Content-Type': 'application/json',
    },
    body: JSON.stringify({
        jsonrpc: '2.0',
        id: 1,
        method: 'tools/call',
        params: {
            name: 'sequentialthinking',
            arguments: {
                thought: 'Analyzing the problem step by step',
                thoughtNumber: 1,
                totalThoughts: 3,
                nextThoughtNeeded: true
            }
        }
    })
});

Docker deployment

# Build image
docker build -t danielapatin/sequentialthinking:latest .
# Or using Make
make build

# Run container (STDIO mode)
docker run --rm danielapatin/sequentialthinking:latest -transport stdio

# Run container (HTTP mode with port mapping)
docker run --rm -p 8080:8080 danielapatin/sequentialthinking:latest -transport http -port 8083

# Run container (SSE mode with port mapping)
docker run --rm -p 8080:8080 danielapatin/sequentialthinking:latest -transport sse -port 8084

Make commands

make help                 # Show all available commands
make build               # Build Docker image
make build-local         # Build local binary
make run                 # Run in Docker
make run-local           # Run locally (HTTP mode)
make run-stdio           # Run in stdio mode
make test                # Run tests in Docker

🔍 Testing and Debugging

Automated testing

# Run all tests
./test.sh

# Run Go unit tests
go test -v
# Or using Make
make test

# Manual stdio mode testing
echo '{"id": "1", "method": "tools/list"}' | ./sequentialthinking-server -transport stdio

HTTP API testing

# Start server in background
PORT=8083 ./sequentialthinking-server &

# List available tools
curl -X POST http://localhost:8083/mcp \
  -H "Content-Type: application/json" \
  -d '{"id": "1", "method": "tools/list"}'

# Call sequential thinking
curl -X POST http://localhost:8083/mcp \
  -H "Content-Type: application/json" \
  -d '{
    "id": "2", 
    "method": "tools/call",
    "params": {
      "name": "sequentialthinking",
      "arguments": {
        "thought": "Analyzing this problem step by step",
        "thoughtNumber": 1,
        "totalThoughts": 3,
        "nextThoughtNeeded": true
      }
    }
  }'

# Connect to SSE stream
curl -N http://localhost:8083/sse

Web interface

Open http://localhost:8080 for interactive testing with visual interface.

🧠 Sequential Thinking Tool

Provides a structured approach to solving complex problems through step-by-step thinking.

Main parameters:

• thought (string): Current thinking step
• thoughtNumber (integer): Current thought number (starting from 1)
• totalThoughts (integer): Estimated total number of steps
• nextThoughtNeeded (boolean): Whether the next step is required

Additional parameters:

• isRevision (boolean): Whether this thought revises a previous one
• revisesThought (integer): Number of the thought being revised
• branchFromThought (integer): Branching point for alternative approaches
• branchId (string): Branch identifier
• needsMoreThoughts (boolean): Indicator of the need for additional steps

Usage examples:

Basic sequential thinking:

{
  "thought": "Starting analysis of the sorting algorithm",
  "thoughtNumber": 1,
  "totalThoughts": 5, 
  "nextThoughtNeeded": true
}

Revising previous solution:

{
  "thought": "Reconsidering the data structure choice given performance requirements",
  "thoughtNumber": 3,
  "totalThoughts": 6,
  "nextThoughtNeeded": true,
  "isRevision": true,
  "revisesThought": 2
}

🔧 Operating Modes and Architecture

📡 Stdio Mode (MCP Compatibility)

• Purpose: Integration with MCP clients (VS Code, Claude Desktop)
• Protocol: JSON-RPC over stdin/stdout
• Launch: ./sequentialthinking-server -transport stdio
• Features: Full compatibility with MCP specification 2025-03-26

🌐 SSE Mode

• Purpose: Debugging, testing, web integration
• Protocol: Server-Sent Events
• Launch: ./sequentialthinking-server -transport sse (default port 8080)
• Endpoints:
  • POST /sse - SSE real-time event stream

🌐 HTTP Mode

• Purpose: Debugging, testing, web integration
• Protocol: HTTP API
• Launch: ./sequentialthinking-server -transport http (default port 8080)
• Endpoints:
  • POST /mcp - MCP requests in JSON format

Dual-mode architecture advantages:

✅ Flexibility: One server for different usage scenarios
✅ Debugging: Web interface for testing and monitoring
✅ Compatibility: Full MCP standard support
✅ Scalability: HTTP mode supports multiple connections

🛠️ Technical Details

System Requirements

• Go: version 1.24 or newer
• OS: Linux, macOS, Windows
• Dependencies: Only Go standard library (no external packages)

Project Structure

sequentialthinking/
├── main.go              # Main server code
├── main_test.go         # Unit tests  
├── go.mod               # Go module
├── go.sum               # Go dependencies
├── Makefile             # Build automation
├── test.sh              # Testing script
├── Dockerfile           # Docker configuration
└── README.md            # Documentation

Building and Deployment

# Clone and build
git clone https://github.com/ad/sequentialthinking.git
cd sequentialthinking

# Local build
go build -o sequentialthinking-server main.go
# Or using Make
make build-local

# Docker build
make build

# Cross-platform builds
GOOS=linux GOARCH=amd64 go build -o sequentialthinking-linux main.go
GOOS=windows GOARCH=amd64 go build -o sequentialthinking.exe main.go
GOOS=darwin GOARCH=arm64 go build -o sequentialthinking-macos main.go

Configuration

• HTTP server port: -port 8080 variable (default 8080)
• Operating mode: determined by presence of -transport stdio flag
• Logging: all logs output to stderr

---

📝 License: MIT License

---

📚 Additional Resources

• 🌐 Model Context Protocol - Official MCP documentation
• 🐙 GitHub Copilot Chat - Copilot Chat documentation

🤝 Support

If you have questions or issues:

1. Check the documentation in this repository
2. Review server logs in stderr
3. Try the web interface for debugging
4. Create an issue in the project repository