Reliability Model

Confidence as operational control

Confidence is a reliability control signal derived from observable pressures: constraints, stability, grounding, anomaly risk, and system health. It gates actions; it does not assert correctness probability.

Developer contract Governance posture

Deterministic

Hard collapse rules

Certain failures deterministically collapse confidence to zero: schema invalidity, required-field absence, or policy violation. Collapse emits action=blocked with explicit flags for audit.

Sensitivity

Stability index

Stability measures sensitivity under perturbation (requery variance, cross-run divergence, structured-field drift). Instability suppresses confidence and promotes review or fallback actions.

Evidence

Grounding strength

Grounding measures support in provided context or retrieval evidence. Weak grounding increases uncertainty flags and prevents automatic downstream action.

Pressure-based computation

Confidence is computed with weakest-link behavior: the system becomes unsafe when any critical signal collapses or degrades sharply.

C = 1.0
if constraint_integrity == 0: C = 0.0
else:
  C *= stability_index
  C *= grounding_strength
  C *= consistency_index
  C *= system_health
  C *= (1 - anomaly_penalty)

Map C → reliability band → deterministic action