Bambu Lab MCP Server

Bambu Lab MCP Server

Model Context Protocol server for Bambu Lab 3D printers

Full control of Bambu Lab printers through Claude AI — MQTT, FTP, camera, AMS, and X.509 auth

Features · Quick Start · Tools · Background

Overview

Complete MCP server for Bambu Lab 3D printers (P1P, P1S, X1C, A1, A1 Mini). Connects over local MQTT for real-time control and monitoring, with FTPS file upload and X.509 certificate signing to bypass firmware authentication restrictions.

25 tools covering print control, status monitoring, camera, AMS filament management, temperature, LED control, and more.

Background

In January 2025, Bambu Lab pushed firmware updates requiring authentication for local LAN printer control, breaking all third-party tools — OctoPrint, Home Assistant integrations, custom scripts, everything.

Community researchers extracted the X.509 certificate and private key from the Bambu Connect desktop application, restoring third-party access. This MCP server builds on that work to provide comprehensive printer control through Claude.

Key references:

• Hackaday: Bambu Connect's Authentication X.509 Certificate and Private Key Extracted — the article that started the workaround
• OpenBambuAPI — reverse-engineered MQTT protocol documentation
• bambu-node — TypeScript library for Bambu printers

Features

• Local MQTT control — Print, pause, resume, stop, speed profiles, G-code execution
• Real-time status — Continuous caching from MQTT reports with cached + fresh status tools
• Camera control — Start/stop recording and timelapse
• AMS management — Change filament trays, unload filament
• FTP file upload — FTPS upload to printer SD card (port 990)
• X.509 signing — Bypass firmware auth restrictions with certificate signing
• Temperature control — Set nozzle/bed temps with safety limits
• Object skipping — Skip failed objects without stopping the print
• Speed profiles — Silent, Standard, Sport, Ludicrous (or raw percentage)
• LED control — Chamber and work lights
• Safety validation — Blocked G-codes, temperature limits, path traversal prevention

Quick Start

Prerequisites

• Node.js 18+
• Bambu Lab printer on your local network
• Developer Mode enabled on the printer (recommended — Settings > LAN Only > Developer Mode)

Install

git clone https://github.com/schwarztim/bambu-mcp.git
cd bambu-mcp
npm install
npm run build

Option A: Developer Mode (Recommended)

Enable Developer Mode on your printer, then configure with your LAN credentials:

# Grab these from your printer screen:
#   IP Address:    WLAN → IP
#   Access Code:   WLAN → Access Code (8-digit)
#   Serial Number: Settings → Device → Serial Number

Add to ~/.claude/user-mcps.json:

{
  "mcpServers": {
    "bambu-lab": {
      "command": "node",
      "args": ["/path/to/bambu-mcp/dist/index.js"],
      "env": {
        "BAMBU_LAB_MQTT_HOST": "192.168.1.100",
        "BAMBU_LAB_MQTT_PASSWORD": "YOUR_ACCESS_CODE",
        "BAMBU_LAB_DEVICE_ID": "YOUR_SERIAL_NUMBER"
      }
    }
  }
}

Developer Mode gives the most reliable experience. All MQTT commands are automatically signed with X.509 certificates.

Option B: Browser Login (No Developer Mode)

If you don't want to enable Developer Mode (e.g., to keep Bambu Handy working), you can authenticate via browser login instead:

npm run setup

This opens Firefox (used instead of Chrome to avoid Google SSO bot detection), lets you log into your Bambu Lab account, and auto-discovers your printers. Credentials are saved to ~/.bambu-mcp/credentials.json and loaded automatically — no env vars needed.

Note: Token is valid for ~3 months. Run npm run setup again to refresh.

Then register with Claude Code (no env vars required):

{
  "mcpServers": {
    "bambu-lab": {
      "command": "node",
      "args": ["/path/to/bambu-mcp/dist/index.js"]
    }
  }
}

Limitations without Developer Mode: Printing .3mf files via project_file command requires Developer Mode. .gcode files and all other commands (stop, pause, resume, status, speed, G-code, camera, AMS) work without it.