Observability

Metrics, logs, traces this function emits.

Observability exposes internal system state for monitoring, debugging, and performance analysis. In SBX, observability encompasses structured logging, error tracking, and metrics collection. Cross-cutting concern checks during FDD4 ensure that observable behavior is built into implementation rather than bolted on after the fact.

PD

Log: validation errors at warn level, metric: validation_pass_rate

MD

Metric: document_create_duration_ms, log: info/error, trace: span

SI

Metric: http_request_duration_ms, log: request/response, trace: distributed

UI

Metric: render_time_ms, log: user actions, trace: client performance

• Structured error handling in API routes projects/sbx/packages/core/go/pkg/api/