Yes, this is great advice. It also applies to interfaces. When we designed a support "chat bot", we went with a diferent architecture than what's out there already. We designed the system with "chat rooms" instead, and the frontend just dumps messages to a chatroom (with a session id). Then on the backend we can do lots of things, incrementally adding functionality, while the front end doesn't have to keep up. We can also do things like group messages, have "system" messages that other services can read, etc. It also feels more natural, as the client can type additional info while the server is working, etc.

If you have to use some of the client side SDKs, another good idea is to have a proxy where you can also add functionality without having to change the frontend.

Creativity is an underrated hard part of building agents. The fun part of building right now is knowing how little of the design space for building agents has been explored.