You don't need a proposal or a finished spec. Tell me what's getting in the way, give me a rough budget if you have one, and leave a way to reach you. A few sentences is plenty.
If you already know roughly what you need, like a Saturday order button, a stream, or a way off clipboards for a warehouse, say so. If you don't, pick "Not sure." That's fine.
What I do with it
I read every message myself. If the project isn't a good fit, I'll tell you. If it is, we talk through the details and agree on a build price and monthly care fee before I start.
Keep the first message simple
Start with the problem and the people who need it solved. If you want to pay in equity, or you need a competitive agency bid, I'm not the right fit.