Chrome canary already had Gemini Nano built in into the browser for local LLM. For the use cases you mentioned there is no need to call a 3rd party.
The fact that Chrome and Gemini are, at least for now, owned by the same company raises huge privacy and consumer choice concerns for me though, and I see benefit in letting the user choose their model, where/how to store their data, etc.
Can't possibly do tool calling well enough to handle browser automation.