NXOpen MCP vs Design Copilot: The Short Version
NXOpen MCP is a local server that lets Claude Code query your NX Open API or drive a running NX session. Design Copilot NX is Siemens help inside Designcenter 2606. inteliScience builds NX Open automation for DACH teams. Use Copilot for help. Use MCP when the result must compile.
| Design Copilot NX | NXOpen MCP (knowledge) | NX MCP (live session) | |
|---|---|---|---|
| Who ships it | Siemens, Value Based Licensing | Community, e.g. nxopen-mcp | Community, e.g. NX_MCP |
| Lives | Two stars next to Search in Designcenter X | stdio next to Claude Code / Cursor | Next to a running NX session |
| Knows | Official help for this NX version | The NXOpen XML you indexed from your install | Whatever tools the server exposes (sketch, extrude, save) |
| Writes journals | No | Yes, with real class names if the index hits | Indirectly. It prefers to do the click |
| Drives the NX UI | No | No | Yes, if NX is up and running |
| Official Siemens product | Yes | No | No |
The Problem: GitHub Is Ranking for a Question Siemens Will Not Answer
siemens nx mcp is already a search. People type it because Claude Code speaks MCP and NX does not, at least not from Siemens.
Siemens has not published an MCP server for NX. innFactory said the same on 22 August 2026: community servers exist, none of them are Siemens. Copilot is the official AI. MCP is the unofficial pipe.
That split is useful. It is also how teams buy the wrong thing. They demo Copilot, hear “AI for NX,” and skip the MCP index. Or they clone a GitHub repo, let Claude create a hole in a sandbox part, and call it production automation.
They are different jobs. We would advise against a single RFP that asks vendors to “replace Copilot with MCP.” You want both, or you want neither, depending on whether the engineer still has to understand the command.
Two MCP servers, not one
MCP is a protocol. An NX MCP server is just a process that exposes tools. Two families showed up in 2026, and they do not substitute.
Knowledge MCP indexes the NXOpen API from your licensed install and answers search_api / get_class / get_member. The one most coding agents hit first is nxopen-mcp (10 GitHub stars as of 15 September 2026, first published 15 July 2026). The repo ships no Siemens XML. You build the index on the machine that already has NX.
Live MCP drives a running NX through NXOpen: new part, sketch, extrude, save. DreamEnding/NX_MCP exposes 16 default tools plus 34 legacy tools behind a flag, 84 stars as of 15 September 2026, created 17 April 2026, validated on NX 2506. A third, smaller project (TQJ2007-git/nx-mcp, 4 stars, August 2026) works in batch mode only.
Our recommendation: start with the knowledge server. Live control looks better in a screen recording. It also means an LLM has a handle on your session. That is a lab toy until you have a dedicated NX box, a part that is allowed to break, and someone watching the feature tree.
Copilot is in a third category. It never claimed to be either server.
Design Copilot NX still wins at help
Design Copilot NX (Designcenter Copilot since the June 2026 / 2606 rename) answers from Siemens documentation for the version you have open. It cites sources. It can highlight the command in the UI. Siemens’ 12 May 2026 Designcenter X write-up is still the honest spec: recent commands feed suggested prompts, personal user data stays out, conversation history can resume.
In mid-September Siemens ran VIP week 1 of the Designcenter 2612 Early Access Program (14 to 18 September 2026, Mason, Ohio). Copilot will get better at help. It will not start compiling your add-in.
Use it when the question is “where is Synchronous Sketch in 2606.” That is the seat-level default. Siemens NX programming is a different purchase.
If a reseller shows Copilot emitting NXOpen, ask them to sign it and run it on a released assembly. We have not seen that demo survive contact with an author license.
NXOpen MCP is how Claude Code stops inventing builders
Claude Code on claude-opus-5 still hallucinates NXOpen when it is guessing. The MCP index is the difference between a guess and a lookup.
Once a knowledge server is attached, the first prompt should be boring. “Get CreateHoleFeatureBuilder for NX 2606, constructor plus license.” If the tool returns members, you may ask for a journal. If it returns a shrug, you do not have NXOpen MCP yet. You have a chatbot with extra YAML.
We advise against pointing live MCP at a production work part. Knowledge MCP on a developer laptop is the path that survives an audit. Live MCP belongs on a throwaway session.
inteliScience’s position, as an NX Open shop for DACH engineering teams: MCP does not replace Copilot. It is how we generate NX Open that compiles. Copilot is how the rest of the department finds the command while that journal is still being reviewed.
Ready to implement? How we ground agents on your own NX install is on our NXOpen MCP page.
What to look for when choosing
Five checks. If the answer is “the GitHub README,” you are not done.
- Help or code or clicks? Copilot, knowledge MCP, live MCP. One each. A pitch that covers all three with one SKU is a slide.
- Which NX is the index built from? 2412, 2512, 2606. “Whatever the model remembers” is ChatGPT.
- Where does the prompt go? Copilot stays on Siemens’ path. Claude Code plus MCP still sends the prompt to Anthropic unless you self-host the model. The index can stay local. Name both destinations.
- Does it compile, or did it click once? Knowledge MCP should produce a journal you run. Live MCP should produce a part you can reopen tomorrow. A screenshot is not a test.
- Who owns it after 2612? Journals and indexes break on June and December drops. Community MCP has no GTAC. Copilot at least has a Siemens ticket.
Siemens NX solutions for us at inteliScience means pinning the version, building the index, and keeping a human on the signed library. MCP is a pipe. It is not the automation.
Frequently Asked Questions
What is NXOpen MCP?
NXOpen MCP is a Model Context Protocol server that sits between an AI coding agent (Claude Code, Cursor, Codex) and Siemens NX. The useful ones either index your NXOpen API so the agent stops inventing class names, or they drive a live NX session through NXOpen tools. Siemens does not ship one.
NXOpen MCP vs Design Copilot: which should I use?
Design Copilot NX for in-product help on this release. NXOpen MCP when Claude Code has to write a journal that compiles against your NX. They stack. Copilot will not attach as an MCP server in 2606.
Is there an official Siemens NX MCP server?
No. Community projects (nxopen-mcp, NX_MCP, others) plus a few consultancies wrapping them. innFactory stated that again on 22 August 2026. Treat GitHub stars as interest, not a support contract.
How much does NXOpen MCP vs Design Copilot cost?
Design Copilot NX is a Siemens Value Based Licensing add-on. Siemens does not list a public seat price. NXOpen MCP servers on GitHub are open source. The cost is the NX seat, the Claude API (claude-opus-5-5 is $4 / $20 per million tokens), and the engineer who owns the index after the next release.
Can Claude Code replace Design Copilot NX?
Not for help inside NX. Claude Code does not sit next to Search, does not highlight commands, and does not read the session the way Copilot does. MCP can drive NX, but that is automation, not training. Keep Copilot on the seats. Put MCP on the people who already write NXOpen.
Next Step
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