MCP server for Claude AI integration via Pendant API (ugs-mcp)

[zackpeters93]

Howdy UGS community,

I wanted to share a project I built that uses the UGS Pendant REST API to give
Claude Code(Anthropic's AI assistant) direct control of CNC machines through the
Model Context Protocol (MCP).

What it does:

• Connects Claude to UGS via the existing Pendant plugin — no changes to UGS needed
• Lets Claude jog axes, home, run G-code files, set work zero
• Includes G-code inspection: translate to plain English, safety check, cycle time
  estimate, tool inventory
• Saves and runs named G-code macros

Safety design:

I was careful here. Every motion command uses a mandatory two-step token protocol:

1. Claude calls the tool → server generates a UUID token and shows a motion preview
   (axis, distance, resulting position, any warnings)
2. User reads the preview → if it looks right, they tell Claude the token
3. Claude calls again with the token → machine moves

Tokens are generated server-side, expire in 2 minutes, and are single-use. Claude
cannot predict, fabricate, or reuse them. It is impossible for Claude to move the
machine without the user actively confirming each step.

Links:

• GitHub: https://github.com/zackpeters93/ugs-mcp
• PyPI: pip install ugs-mcp
• Tested on: SainSmart Genmitsu 3018 Pro (GRBL) with UGS 2.x

Wanted to share in case it's useful to others in the community. I'm also happy to
discuss whether it makes sense to add a note about this in the UGS docs or wiki —
the Pendant API integration was the key that made this possible, and I think other
people might want to know it exists.

Thanks for building such a solid platform.
— Zack