Brex tried the obvious approach to keeping AI agents in line: govern the code. It didn’t work. So the fintech company built something different, an HTTP/HTTPS proxy called CrabTrap that monitors what AI agents actually do at the network level, using a language model to make judgment calls on unfamiliar traffic patterns.
The company open-sourced CrabTrap on April 21, 2026, and the project has already racked up more than 700 stars on GitHub.
Why code-level governance fell short
Brex’s journey to CrabTrap started with a problem most companies building AI agents will eventually hit. Their earlier OpenClaw agent framework revealed that traditional SDK-level governance, the kind that tries to constrain agent behavior through code-level controls, was fundamentally inadequate for agents that hold sensitive credentials like API keys and OAuth tokens.
Pedro Franceschi, Brex’s co-founder and CEO, described the network layer as an “untapped enforcement point” for agent governance.
