Think Tool Server implements Anthropic's "think" tool to provide Claude with dedicated structured reasoning capabilities for complex problem-solving tasks. It creates a scratchpad space where Claude can break down multi-step problems, verify policy compliance, analyze tool outputs, and plan approaches before executing actions. Key features: - Structured thinking space for complex reasoning and decision-making - Policy adherence verification before taking actions - Analysis of tool results and web search data for correctness - Multi-step problem decomposition and planning - Iterative reasoning validation to catch logical errors or biases

MCP Think Tool Server

[](https://smithery.ai/server/@cgize/claude-mcp-think-tool)

A Model Context Protocol (MCP) server implementing the "think" tool for improving Claude's complex reasoning capabilities.

Overview

This MCP server implements Anthropic's "think" tool, which provides Claude with a dedicated space for structured thinking during complex problem-solving tasks. As described in Anthropic's blog post, the think tool has been shown to significantly improve performance in complex tasks requiring policy adherence and reasoning in long chains of tool calls.

Custom Instructions

Add these custom instructions to Claude to optimize its use of the think tool:

You have access to a "think" tool that provides a dedicated space for structured reasoning. Using this tool significantly improves your performance on complex tasks. 
When to use the think tool 
Before taking any action or responding to the user after receiving tool results, use the think tool as a scratchpad to: 
List the specific rules that apply to the current request 
Check if all required information is collected 
Verify that the planned action complies with all policies 
Iterate over tool results for correctness 
Analyze complex information from web searches or other tools 
Plan multi-step approaches before executing them 
How to use the think tool effectively 
When using the think tool: 
1. Break down complex problems into clearly defined steps 
2. Identify key facts, constraints, and requirements 
3. Check for gaps in information and plan how to fill them 
4. Evaluate multiple approaches before choosing one 
5. Verify your reasoning for logical errors or biases

Key Use Cases

Installation

Installing via Smithery

To install Think Tool Server for Claude Desktop automatically via Smithery:

npx -y @smithery/cli install @cgize/claude-mcp-think-tool --client claude

Manual Installation

npm install -g @cgize/mcp-think-tool

Configuration

Add this configuration to your MCP configuration file:

{
  "mcpServers": {
    "think-tool": {
      "command": "npx",
      "args": [
        "-y",
        "@cgize/mcp-think-tool"
      ],
      "type": "stdio",
      "pollingInterval": 30000,
      "startupTimeout": 30000,
      "restartOnFailure": true
    }
  }
}

Configuration file location:

If installed globally, you can also use:

{
  "mcpServers": {
    "think-tool": {
      "command": "claude-mcp-think-tool",
      "args": [],
      "type": "stdio",
      "pollingInterval": 30000,
      "startupTimeout": 30000,
      "restartOnFailure": true
    }
  }
}

Available Tools

Example Prompt

Using the think tool, solve this multi-step problem:
A train travels at a constant speed of 60 km/h. It departs from station A at 9:00 AM and arrives at station B at 11:30 AM. What is the distance between stations A and B?

License

MIT