Simulated callers not responding in some simulation runs

Timeline

1. ResolvedSep 28, 2026 at 12:50AM

   Impact window: 2026-09-27, 23:45–00:50 UTC (~65 minutes) During this window, some simulation runs were affected. In those calls the simulated caller could not generate responses. It gave generic replies such as "Sorry, could you say that another way?" or stopped responding, and the call ended early. What happened Requests from the agent service to an upstream language model provider used by our simulated callers were rejected for the duration of the window, so the simulated caller had nothing to say. Resolution Service was restored and simulated callers have been responding normally since the end of the window. Data impact No data was lost. Results from simulation runs started in this window do not reflect your agent's behaviour and can be safely rerun. Next steps We're adding safeguards so an issue with an upstream model provider does not stop simulations, and changing how these failures are reported so affected runs are marked as a platform error rather than as agent behaviour.