It has concurrency with Promise; it doesn't have parallelism.

And these agents are all network I/O bound by the model services so a lot of use cases don't need threading.

I would argue that python is the overrated language when it comes to building agents. Just because it's the language of choice for training models doesn't mean it should be for building apps against them.

The dx typescript brings to these types of applications is nice.

No real concurrency. No scheduling. If you are not working with a lot of IO then js would be a poor choice. But in this case we talk about network calls, so definitely IO. The settimout, promise, request methods will do their job.