Ask HN: What's the best way to build agents in Oct 2025

I know this a broad question, but I'm a bit overwhelmed by all the available frameworks and rapidly changing ecosystem. Not looking for a detailed approach, just would really appreciate any resources or favorite frameworks to get me pointed in the right direction.

I'm familiar with writing a basic chat loop with tool calls, and the basics of MCP.

Ideally would to be able to use different foundation and specialized models, not be locked into a specific vendor, and be able to work with memory (I think).

Thanks so much!