--> The solution involves integrating a prompt-based paywall, which requires chat users to purchase a subscription via Stripe and validates the subscription by verifying the user’s email at the start of every conversation.

So no free tier/trial? I would highly recommend you implement a paywall after /near the user's "aha" moment. If that is after one chat / part of one/ multiple interactions that is where it needs to be.

You are in a growing market and are trying something different, you need to let prospects experience what differentiates you, before asking for a credit card. Esp if your audience is early-adopter, techies.