up

src/Policy/StellaOps.Policy.Engine/Scoring/RiskScoringModels.cs

@@ -1,4 +1,5 @@
 using System.Text.Json.Serialization;
+using StellaOps.Policy.Scoring;
 
 namespace StellaOps.Policy.Engine.Scoring;
 
@@ -142,4 +143,18 @@ public sealed record RiskScoringResult(
     [property: JsonPropertyName("signal_contributions")] IReadOnlyDictionary<string, double> SignalContributions,
     [property: JsonPropertyName("override_applied")] string? OverrideApplied,
     [property: JsonPropertyName("override_reason")] string? OverrideReason,
-    [property: JsonPropertyName("scored_at")] DateTimeOffset ScoredAt);
+    [property: JsonPropertyName("scored_at")] DateTimeOffset ScoredAt)
+{
+    private IReadOnlyList<ScoreExplanation> _explain = Array.Empty<ScoreExplanation>();
+
+    /// <summary>
+    /// Structured explanation of score contributions.
+    /// Sorted deterministically by factor name.
+    /// </summary>
+    [JsonPropertyName("explain")]
+    public IReadOnlyList<ScoreExplanation> Explain
+    {
+        get => _explain;
+        init => _explain = value ?? Array.Empty<ScoreExplanation>();
+    }
+}

src/Policy/StellaOps.Policy.Engine/TASKS.md

@@ -5,3 +5,4 @@ This file mirrors sprint work for the Policy Engine module.
 | Task ID | Sprint | Status | Notes |
 | --- | --- | --- | --- |
 | `POLICY-GATE-401-033` | `docs/implplan/SPRINT_0401_0001_0001_reachability_evidence_chain.md` | DONE (2025-12-13) | Implemented PolicyGateEvaluator (lattice/uncertainty/evidence completeness) and aligned tests/docs; see `src/Policy/StellaOps.Policy.Engine/Gates/PolicyGateEvaluator.cs` and `src/Policy/__Tests/StellaOps.Policy.Engine.Tests/Gates/PolicyGateEvaluatorTests.cs`. |
+| `DET-3401-011` | `docs/implplan/SPRINT_3401_0001_0001_determinism_scoring_foundations.md` | DONE (2025-12-14) | Added `Explain` to `RiskScoringResult` and covered JSON serialization + null-coercion in `src/Policy/__Tests/StellaOps.Policy.Engine.Tests/Scoring/RiskScoringResultTests.cs`. |