Debug logs

Collect diagnostics

Exo reuses Core DebugConfig, which must be set before constructing Sdk. During execution inspect:

const auto domain_health = exo.health();
const auto device_health = device.health();

Health provides ok, warning/error counts, and bounded diagnostics. Preserve the complete what() value of qnbot::QnBotError. A useful report includes SDK/Core versions, platform architecture, port, log lines around the first failure, and the reproducing command.