Engineering & Product
Deep dives into how we build Agent Billy.
Why We Only Accept Restricted API Keys
Your Stripe secret key is the most powerful credential in your business. We explain why Agent Billy will never accept it, and how restricted keys give us everything we need and nothing we don't.
Stripe's agent wallet lets bots pay you — subscriptions are where it breaks
Stripe's Link wallet now pays on behalf of Meta, xAI and other agents, so here is what a shared payment token can and cannot do to a SaaS subscription, checked against the docs on 28 September 2026.
How to Upgrade Your Stripe API Version Without Breaking Billing
A pinned Stripe API version costs you quietly — here is what has changed since 2024 and how to move onto the current version using simulations, dual webhook endpoints and the 72-hour rollback.
Stripe Agreed to Buy OpenRouter. What It Means for Usage-Based Billing
Stripe has agreed to buy the gateway that routes AI model traffic — the deal has not closed yet, and here is what teams billing on Stripe should watch before it does.
5 Reasons Business Owners Shouldn't Share Their Stripe Login
Sharing your Stripe password feels harmless until it isn't. Here are five real risks and what to do instead.
Stripe's Team Roles Decide Who Can Refund. Billy Decides How Much.
Stripe now ships about twenty built-in team roles on every account. They're good, and you should use them. Here's what they still don't do, and where Billy fits.
How to Give Employees Stripe Access Without the Risk
Your team needs to process refunds, update subscriptions, and answer billing questions. But Stripe dashboard access means exposing bank details, API keys, and payouts. Here's the fix.
Building a Culture of Billing Transparency With Audit Logging
When everyone can see who did what and when, trust goes up and mistakes go down. Here's how audit logging transforms team billing operations.
MCP vs API: Why AI Agents Are the Future of Billing Management
Stripe has an API. Stripe has an MCP server. Agent Billy has an MCP server. What's the difference, and why does it matter for your team?
How Per-Customer Container Isolation Works
Every Billy customer gets their own isolated Azure Container App. Here's the architecture, why we chose it, and what it means for your data security.
Building Role-Based Access Control for Stripe
Stripe's permission model is binary: you either have the key or you don't. We built a four-tier RBAC system on top of the Stripe API. Here's how.
Agent Billy as an MCP Server: Billing in Plain English
We shipped Model Context Protocol support so you can manage Stripe from Claude, Cursor, or any MCP-compatible AI tool. Here's how we built it.
Why We Sync Stripe to a Local Database
Calling Stripe's API on every page load is slow, rate-limited, and expensive. We sync all your Stripe data to a Postgres instance that loads in under 100ms.
The Billing Bottleneck Problem Every Growing SaaS Hits
You've crossed 10 employees. Now every refund, every subscription change, every invoice question lands in one person's inbox. Here's why that happens and how to fix it.