TokenTrail: auto-invoice your customers for LLM usage.The billing layer between Helicone and Stripe.

I have seen companies keep getting hit with surprise LLM bills, retry loops, users spamming AI features, and no way to know which customer caused a cost spike. So I started building TokenTrail to fix it for myself and figured others might have the same problem.

What it does:

• Set hard budget limits that kill requests at $X (no more Monday morning surprises, though customisable from the user side)

• Track cost per customer, not just total API spend

• See what each step in a multi-agent workflow actually costs

• Basic smart routing to cheaper models for simple queries

• LiteLLM integration

It's early; zero users. The UI is functional.

You can poke around the demo here: https://tokentrailapp.com/demo (not everything works yet, but it gives you the idea)

Full site: https://tokentrailapp.com

Would love feedback on whether this is useful or if most teams just build this stuff in-house.

What's missing?

What's pointless?