ChatGPT did the CAD task locally, the result was so-so
u/event-maker let ChatGPT read and write files locally through MCP and finish a CAD task. It asked about the requirements one by one and kept going for nearly an hour. The result was so-so. He then built a skill where ChatGPT plans and a local agent step executes.
Done with ChatGPTModerate
What was done
On 06 July 2026 u/event-maker writes that ChatGPT can read and write files on a local machine through MCP. He used that for a CAD task. ChatGPT asked about the requirements one by one, and worked for nearly an hour with several sub-agents. The CAD result itself was so-so. He writes that ChatGPT is better at planning and review, while a local coding agent such as Codex is better at small steps, files, commands and checks. He built a small skill to standardise that split, with some safety boundaries. The original CAD file is not named.
How it went
The CAD task was finished, and he calls the result so-so. The file name is not in the post.
Worth knowing
The program and the file are not named. Nearly an hour is his time span, not a clock time. The skill is described without a new finished result.
How to do it
- Point at the file and ask the agent to ask about the requirements before it writes.
- Let it work on a copy, and look at the result yourself.
- Take in the change yourself if the result holds. Otherwise say what is so-so.
Try it with ChatGPT
Read [file] and make [change] in a copy. Ask me about the requirements before you write. Do not overwrite the original until I say yes.
Replace text in brackets with your own.
Done when. The copy has been seen, and the original has not been overwritten without a yes.
Safety rule. The original is not overwritten until you have said yes.
Read the original
Read the original · u/event-maker on Reddit ·