Default LLM for tools and context from async tasks

[Valdemar1863]

1. I see that tools use OpenAI LLM by default. But how can I change an LLM provider for them?
2. I can't write a context from async tasks myself, I can only choose only 1 option which is (at least in my case) a repetition of a task which causes an agent to stuck in an infinite loop.