what's your basic SEO tool stack?

I’d probably go with Google Search Console, Google Keyword Planner, and maybe Semrush or Ahrefs for keyword search. There are so many tools out there, but I think these are a good starting point without making things too complicated lol.

agree on the subscription complaint, thats why my stack is mostly one off buys. gsc and ahrefs free tools for basic checks, gsa ser one time, and a scraper i bought years ago (now just extracting here n there for other jobs lol, i dont scrape link targets anymore). i buy a verified list instead, cheaper than the proxies and processing my own targets. whenever i need more research data i use dataforseo through hermes, pay as you go instead of keeping another subscription. not the whole ahrefs app, but enough for the occasional serp and backlink checks i need

If you are smart, you can connect different API to your AI Agent and ask him which data that will be useful to make a strategy for your business.
No tool subscription. (Except maybe your AI one)