I think one thing that people are sleeping on is passing a ton of secrets to OpenAI and Anthropic or your OpenRouter by having a .env or secrets on disk in your repo, but not checked in Your LLM will happily read the entire file, ship it off to be training data for future versions of ChatGPT, and not raise any flags, because let's be fair it was on ok thing to check if all the env vars were set, or it you had set up…
Besides leaking, it's easy to oopsie and DoS a system or send malformed requests in the course of testing and development. You don't want a surprise $1k bill cause someone was working on some test automation and accidentally sent thousands of real results in the process.