Perplexity today open-sourced Numbat, a detection and response layer across agent frameworks, providing security teams with visibility into agent activities and the ability to prevent selected actions before execution. Numbat supports desktop, CLI, IDE, and gateway agents, featuring real-time monitoring, local detection, pre-action blocking, and session forensic reconstruction, available in a single Go binary for macOS, Linux, and Windows, under the Apache 2.0 license. Perplexity previously focused on search and AI assistant products, with the open-sourcing of Numbat as an external version of an internal tool aiming to address risks associated with the expanded permissions of agents. The motivation behind the Apache 2.0 open-source and collaboration with the Open Secure AI Alliance is to establish a detection flywheel, promote industry standards, and reduce security concerns for enterprises adopting agents.