I personally dont disclose mine because I dont have to. I barely stutter these days and it's not very noticeable at all. If u have a severe stutter that might interrupt the flow of the conversation then I think it would probably be in your best interest to do so but if it is a mild or moderate stutter, just letting them figure it out is ok i guess. I feel like this also depends on the type of conversation you are having. If it's a friendly or casual convo then you can just let them figure it out if you want but if it is in a professional setting you should definitely give a heads up. You also dont have to say it as the very first thing because, yes, that would be very awkward. Just let the conversation start and when you start stuttering or stumbling you can just say "I have a speech problem" and just continue what you were saying, a sensible person SHOULD be understanding and compassionate of ur situation.