I was waiting for this for 2 months then I encountered openai-agents-js, which is a well-implemented JS port from a young developer. I found the library really cool. Actually if you know what the original SDK actually does, despite many people think it does magic, an unofficial port is very okay and safe.
So, I started to implement a new system using this and it is working in production for more than a week without an issue. It has almost every feature the original SDK has and the maintainer quickly implements a feature when it is added to the original one. API is very intuitive. I’m using almost all the features and there is almost no bugs.