Spanda

Root Cause Analysis

Leverage the mission replay system to diagnose failures from recorded traces.

CLI

spanda diagnose examples/showcase/root_cause_analysis/mission.trace
spanda diagnose examples/showcase/root_cause_analysis/mission.trace --json

What is analyzed

Triggers and scheduler events
Messages and topic activity
Provider calls (including failures)
Safety decisions and kill switch activations
Health status changes
Failure events

Output structure

Root Cause
provider_call: {"failed": true, "module": "positioning.gps", ...}

Contributing Factors
* Provider call failures detected
* Safety rules triggered during mission

Timeline
  T+0ms provider_call — ...
  T+1500ms health_change — GPS fix lost
  T+2000ms provider_call — GPS read failed
  T+2100ms safety_stop — navigation uncertainty

Recommended Actions
* Verify provider connectivity and credentials
* Review safety zone and stop_if thresholds
* Replay mission with --deterministic for confirmation

Workflow

Record a mission: spanda run --record --trace-out mission.trace
Diagnose: spanda diagnose mission.trace
Confirm with deterministic replay: spanda replay mission.trace --deterministic

API

use spanda_readiness::{diagnose_trace, RootCauseReport};