Start with the problem.

The most useful first message describes the problem rather than the solution. What is not working, what it is costing, and what you have already tried tells us far more than a feature list — and it lets us tell you quickly whether we are the right people, which is the answer you actually want.

Useful to include if you have it: the systems involved, roughly when you need it working, and who inside your organisation owns the decision. None of it is required. A paragraph is fine.

We are not a sales organisation with a delivery arm, so nobody is going to chase you with a sequence of follow-ups. You will get one reply from the person who would do the work, and if we think the project is a bad idea we will say so then.