Stack-chan MCP Server

Overview

Stack‑chan is a fully programmable, M5Stack‑based robot that brings a touch of “super‑kawaii” charm to embedded AI projects. By exposing its functions through the Model Context Protocol, developers can let an AI assistant control facial expressions, speech output, and even motorized servos—all from a single MCP client. The robot’s firmware is written in JavaScript, enabling rapid iteration and easy integration with web‑based tooling or Node.js environments. This makes Stack‑chan an ideal platform for prototyping conversational agents, teaching robotics concepts, or creating interactive displays that respond to natural language commands.

The server’s core value lies in turning a hobbyist robot into an extensible AI‑controlled device. Instead of writing custom drivers or dealing with low‑level I²C/SPI communication, an assistant can invoke high‑level actions such as “make Stack‑chan smile,” “say hello,” or “turn the head to look left.” The MCP interface abstracts these capabilities into simple, typed resources and tools, allowing developers to compose complex behaviors without worrying about the underlying hardware details. This abstraction also opens the door for multi‑assistant orchestration, where several AI agents can coordinate to animate the robot in real time.

Key features of Stack‑chan include:

• Expressive face: The robot can display a range of emoticons—happy, angry, sad—and even custom face shapes using its built‑in OLED display.
• Speech synthesis: With a speech balloon tool, the robot can vocalize messages or display text, making it useful for public demos and teaching assistants.
• Servo control: PWM servos can be driven via serial/TLL, enabling head turns, arm movements, or other mechanical gestures.
• Modular add‑ons: The “bulb” feature allows additional M5Units (sensors, LEDs, etc.) to be attached, expanding the robot’s sensory and actuation capabilities.
• JavaScript firmware: The entire control logic is written in JavaScript, facilitating quick prototyping and integration with web‑based AI workflows.

Typical use cases span education, customer engagement, and research. In a classroom setting, teachers can let students program Stack‑chan to respond to voice commands or sensor inputs, turning abstract concepts into tangible demonstrations. In a retail environment, an AI‑powered kiosk could use Stack‑chan to greet visitors with friendly animations and voice prompts. Researchers exploring human‑robot interaction can employ the MCP interface to test different conversational strategies while observing real‑world physical responses.

Integration with AI workflows is straightforward: an MCP client sends a request to the Stack‑chan server, specifying the desired tool (e.g., “say”) and parameters (the text to speak). The server translates this into low‑level commands that the M5Stack hardware executes. Because the interface is standardized, any Claude or other AI assistant capable of speaking MCP can control Stack‑chan without custom adapters. This plug‑and‑play capability, combined with the robot’s cute appearance and flexible hardware, makes Stack‑chan a standout tool for developers looking to bring lively, responsive robots into their AI ecosystems.