Honestly, never been on a team that stuck to TDD. As you test your stuff, and understand whatever libraries and apis you're calling you modify your implementation as you go.

For public facing methods, especially ones called by customers, having pre agreed upon tests matter more but usually that's at the integration test and system test level. I usually use AI for unit testing and read what was written. Tests end up being a lot of writing harnesses and setting up mocks that you delegate to the model and if there's gaps or incorrect requirements, you change them.

I would never let the agent define the code structure. It doesn't understand business processes or what might need to be extended or we're instead about.

I've been doing software for a while, I know how to review code. I don't vibe code, I let the model implement boilerplate and mapping functions while I do other stuff, like manual testing or talking with product. If done correctly, you can incorporate generative models into your workflows without fully handing over all control.

Wikipedia says:

Vibe coding involves accepting AI-generated code without reviewing it,

If you are using LLMs to write e.g. small components, then you are typically understanding the structure of the program, and reviewing it.

Vibe coding is you not reviewing what the model outputs. I read every line, often give feedback and tell the model about patterns I want to use.

I probably write like 60-70% of the code myself.