It usually startswith an email.
Tell us about your system, your product, or the workflow you want AI to take over. Three honest sentences beat a ten-page brief. Replies come from an engineer, not a funnel.
What the thing is, what it has to do, and what is currently in the way. Rough is fine. A constraint you already know about is worth more than a specification written to sound finished.
A reply, then a conversation. If the work is not a fit, we say so and point elsewhere; that costs everyone less than finding out three weeks in.