# How TCP Socket Communication Works Between the Blender MCP Server and Blender Addon

> Learn how TCP socket communication connects the Blender MCP server and addon. Discover how the addon acts as a server for remote LLM-driven Blender command execution via JSON.

- Repository: [ahujasid/blender-mcp](https://github.com/ahujasid/blender-mcp)
- Tags: internals
- Published: 2026-04-13

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**The Blender MCP integration establishes a persistent TCP socket where the Blender addon acts as a server listening on `localhost:9876`, while the MCP server acts as a client that sends JSON-encoded commands and receives JSON responses, enabling LLM-driven tools to execute Blender commands remotely.**

The blender-mcp project bridges large language models with Blender by implementing a bidirectional TCP socket connection between the MCP server and a Blender addon. This architecture allows external AI agents to query and manipulate Blender scenes without running inside the Blender process itself, using a simple request-response protocol over a local network