Start with whatever chatbot you already have. If you are new to this, or the automation is small, a normal ChatGPT or any chatbot will do the job perfectly well and you do not need to pay for anything extra. The xlwings videos and guides here are demonstrated in Google AI Studio, which is great for learning and getting started.
The switch point is not difficulty, it is length plus iteration. The difference shows up when the code gets longer and you are changing it often. At a few hundred lines you end up copying the whole script in and out of a chat window on every single iteration, and that copying becomes the slow part - not the thinking. An AI coder reads and edits the file directly, so that step goes away entirely. That is the whole argument; if you are not feeling that pain, you do not need one yet.
If you go paid: any AI coder works - Claude Code, Cursor, Codex and others. Personal experience, offered as one data point rather than a benchmark: I used Cursor earlier and now use Claude Code, finding its overall coding ability far better.
If you want free (with limits): Google Antigravity works very well with xlwings Lite, and it is already included if you pay for the Google subscription.
Whatever you pick, upload the AI Coder Instructions file (free, in the xlwings guides). It is a rulebook that bridges what LLMs do not know about the xlwings Lite environment - golden rules, error patterns, proven snippets - and it makes a noticeable difference to output quality, Antigravity included.
Guides, the instruction file, and live xlwings apps: https://www.tigzig.com/xlwings-starter. Related: xlwings Lite vs Claude in Excel and how to learn Python in Excel.
Building something like this? How I work covers the rates, the availability and what I take on.