AI agents are crossing a line that traditional software never had to. They read your Slack, draft your emails, push code, update your CRM, and pay your invoices. To do that, they need keys to systems that belong to specific people. Not the application. Not the company. The person.
That is the entire reason per-user OAuth exists in the agent context, and it is the difference between a side project and something a customer will trust with their Gmail account.
This article breaks down what per-user OAuth means for AI agents, why shared credentials fall apart at scale, what the emerging standards look like, and the exact checklist to use when picking a platform to handle it. We will also show how Composio approaches each of these problems so you do not have to assemble the stack yourself.
The problem with the way most teams start
Most agent prototypes start with a single API key in an environment variable. It works for one developer, on one machine, for one demo. The moment a real user shows up, the model breaks.
