I've created exactly this for myself: https://v3rtical.tech/public/sshot.png
It runs locally, but it uses API keys for various LLMs. Currently I much prefer QwQ-32B hosted at Groq. Very fast, pretty smart. Various tools use various LLMs. It can currently generate 3 types of documents I need in my daily work (work reports, invoices, regulatory time-sheets).
It has weather integration. It can parse invoices and generate QR codes for easy mobile banking payments. It can work with my calendars,
Next I plan to do the email integration. But I want to do it properly. This means locally synchronized, indexable IMAP mail. Might evolve into actually usable desktop email client (the existing ones are all awful). We'll see...