Bruno: Fast and Git-friendly open-source API client (Postman alternative) 2 years ago
I use ZAP [1] with the OAST add-on for this at the moment. I admit the UX isn't perfect, but it serves my purpose.
If I also want control over the responses (e.g. return a 401 status code for every fifth request), I have a custom extender script [2] for that.
[2] https://www.zaproxy.org/blog/2022-09-13-zap-extender-scripts...