A 200 OK That Lied: How Silent Failures Hide Inside Agent Logs
DigitalOcean's own framing of the problem is blunt: a tool call can return a clean success code and still be wrong. The company's illustrative case is a breaking change to an internal refund CLI tool that silently switched units from dollars to cents, causing a support agent to issue refunds at 1% of the intended value while every log line reported success [1]. Signals is built to catch exactly that class of failure by watching live traffic on Managed Agents and the Inference Engine and sorting problem sessions into three buckets - interaction signals (a frustrated user), execution signals (an unreliable tool call), and environmental signals (an infrastructure fault) - without requiring teams to add any extra instrumentation [1]. On the tau-bench benchmark, DigitalOcean reports Signals reaches an 82% informativeness rate and a 1.52x efficiency gain over randomly sampling sessions for review [1], a concrete claim that the flagging is doing more than just surfacing noise.


