Google Agent Anomaly Detection scores on five public agent-security benchmarks

Google ran its Agent Anomaly Detection, in Private Preview on Gemini Enterprise Agent Platform, against five public agent-security benchmarks it did not write, scoring 1,774 sessions. It flagged 87% of harmful instructions the agent actually carried out, with false alarms on 2% to 16% of benign sessions, and caught only 4 of 18 sessions where poisoned long-term memory drove the agent to act. The tests used an agent built with the Agent Development Kit (ADK) on gemini-2.5-flash, covering AgentDojo, InjecAgent, Agent Security Bench, AgentDyn and AgentHarm.