Think MCP is an MCP server implementation that provides a dedicated think tool to enable structured reasoning within agent workflows. It mirrors the concept from Anthropic's think tool, allowing an AI agent to pause and record an explicit thought during complex reasoning or multi-step tool use. Importantly, the tool does not modify the environment or database; it simply appends the thought to a log, aiding processing, backtracking, and adherence to policies. This makes it useful for tool output analysis, policy-heavy environments, and sequential decision making where each step builds on the previous one. The project is described as a minimal, standards-based MCP server built on mcp[cli], designed for easy integration with Claude or other agentic LLMs. An advanced mode adds extra tools (criticize, plan, and search) to extend reasoning capabilities. Configuration examples demonstrate registering the server under mcpServers with command, arguments, and enabled flags, and show an optional environment block (e.g., TAVILY_API_KEY) for advanced usage. The work is inspired by Anthropics’ engineering blog on Claude’s think tool and is released under MIT.