PTC has launched its new FeatureScript MCP Server capability for Onshape allowing users to create custom CAD features using natural language and AI.
Via its Onshape Labs initiative, the capability lets users describe the functionality they want, and AI automatically helps build, test, debug and refine the custom feature in FeatureScript until it works as intended.
By using this companies are able to very quickly automate repetitive design tasks, create custom design tools tailored to their existing workflows and capture engineering knowledge through the process.
Sample examples include a feature generated by feeding the AI a PDF of standard definitions allows users to apply complex helixes with a single click. Developing tools for wire shelving and sink racks that automate grid patterns and support structures based on user-defined parameters. It can build custom tools and buttons expressly for your own familiar bottlenecks and often repeated tasks.
“Our feature script is an abstraction language that we use to build our own features, and we’ve open sourced all that. We feel that it allows you to go deeper and actually build new buttons – you can build features that are missing, you can build specific things that you need, and we’ve had customers do that. Our our intention with that is to allow people to customise the CAD system to meet their needs,” said Darren Henry, senior VP General Operations PTC Onshape in a special preview given to DEVELOP3D.
“What we’re finding is that, as you know, AI loves to code and with only Onshape you now can have the robust standard tool sets, and then you can extend them to your specific needs.
“You can build your new features. So we believe that the Onshape advantage here is to have a robust standard CAD system that’s been tailored exactly to your needs.”
FeatureScript MCP Server extends its capabilities to coding LLMs that many users already have access to – such as Claude, ChatGPT, and Gemini. Built on the Model Context Protocol (MCP), engineers can connect AI directly with Onshape FeatureScript code.
While it’s been possible to ask an AI to generate FeatureScript features for years now, what’s really unique about FeatureScript MCP is it also tests and evaluates the features.
“It’s inserting code, it’s testing the code, it’s evaluating the output, it’s been rewriting code if necessary. It’s evaluating its own output to determine to meet the goal, and is doing this all autonomously on its own,” states Cody Armstrong, senior director Onshape AI Innovation.
The other element, and one that Onshape is very excited about, is the notion of persistent memory, which the FeatureScript MCP Server is equipped with, meaning that over time, your agent will improve.
“It’s writing to its own memory about what its past interactions were, with the goal of avoiding errors in the future,” said Armstrong. “Where an agent will learn over time by writing and reading from notes about how and what they’ve done in the past, past errors, and resolutions to them.”
FeatureScript MCP Server does not simply exist to create functions and features for the CAD itself, but can also work with external LLMs to create prompts that can build CAD models that for a lot of companies will be standard conforming features.
An example of a shell and tube heat exchanger shows a fully built model of the assembly built without a single line being sketched by a human. Further to the 267 part assembly, it is also an implemented cut list, features weld schedules and all kinds of other tables that can help users report on what this feature is doing.
The more information that the user can provide the LLM with – images, PDFs, any standards or company guidelines – then the better the quality of the initial output, but a feature can still be successfully built from a simple prompt.
“The future of AI in CAD is not simply text-to-CAD, but text-to-code-to-CAD,” said David Katzman, EVP and GM, Onshape and Arena at PTC.
“The real value of AI is helping engineers turn proven ideas into tools they can use again and again. With the new FeatureScript MCP Server, Onshape has become the most customisable production CAD system, empowering all users to build engineering capabilities tailored to their company’s products and processes.”
