Public failures use AntigravityCliSdk.Error; streaming failures use AntigravityCliSdk.Types.ErrorEvent.

Unsupported completion_only and output_schema requests return kind: :unsupported_capability. The error context preserves the provider, feature, activating option, and support state supplied by CliSubprocessCore.ProviderFeatures.Error.

Lifecycle failures are distinct:

  • stream_timeout means no event arrived within timeout_ms;
  • run_deadline_exceeded means the total non-rearming ceiling elapsed;
  • transport failures retain normalized Core transport context;
  • provider process failures retain stderr tail and truncation state.

No error path includes the API key in argv or formatted diagnostics.