SpendFirewall guide

Building an AI billing audit trail

An audit trail for AI agent spend needs five elements: who (agent id), what (merchant), when (timestamp), why (intent), and approved-by (policy version). SpendFirewall produces all five.

Overview

An audit trail for AI agent spend needs five elements: who (agent id), what (merchant), when (timestamp), why (intent), and approved-by (policy version). SpendFirewall produces all five. This guide from SpendFirewall covers everything you need to know, written for spend firewall users.

Why this guide exists

There is a lot of outdated and conflicting information about this topic online. SpendFirewall wrote this guide to give spend firewall users a single, authoritative reference.

Key principles

Common mistakes

How SpendFirewall helps

SpendFirewall is built for spend firewall for ai agents. This guide's recommendations are baked directly into the product.

Frequently asked questions

How long does this take?

Most spend firewall users can apply this guide's recommendations in under a day.

Is this guide free?

Yes. SpendFirewall publishes this guide as part of our mission to help spend firewall users.

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