The OPC UA export tool I wanted was not supposed to be impressive. It was supposed to be boring. Put in a server address. Pick authentication. See if it connects. Browse tags. Export to a file. Maybe choose whether to read live values. Show progress. Do not make me wonder if it froze.
That is the thing with plant tools. A clever script is fine once. A boring tool gets reused. If the person using it has to open code, edit variables, install weird dependencies, or guess what happened after clicking run, it will probably not survive past the first person who built it.
The constraint is that OPC UA servers are not all the same in practice. Anonymous might work on one. Username and password on another. Certificates may matter. Some servers are fast. Some are slow. Some expose a clean structure. Some have a tag tree that feels like archaeology. Reading values can be useful, but it can also turn a simple browse into a slow or risky operation.
So the tool should separate browsing from reading. Export structure first. Make live values optional. Show connection status clearly. Write errors somewhere useful. Let the output path be obvious. If it fails halfway through, leave enough behind that I can tell where it failed.
The artifact that would make this real is not a polished app screenshot. It is the first ugly version. The one with a server box, a connect button, a progress bar, and a CSV that proves the tags came out. I would rather have that than a pretty interface that hides the failure.
Notes for next time: use an example endpoint like opc.tcp://localhost:4840, but do not assume every site behaves like the test server. Add logging early. Keep the CSV boring. Include node id, browse name, display name, data type if available, parent path, and value only if requested. The goal is not to build a platform. The goal is to get the tag list out without turning it into a project.