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docs/features/checked/cli/policy-simulation-reachability-overrides.md

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+# Policy Simulation Reachability Overrides
+
+## Module
+Cli
+
+## Status
+VERIFIED
+
+## Description
+What-if reachability overrides in policy simulation: override reachability states (reachable/unreachable) and scores for specific vulnerabilities or packages to model hypothetical scenarios.
+
+## Implementation Details
+- **Command Group**: `src/Cli/StellaOps.Cli/Commands/PolicyCommandGroup.cs` -- policy simulation commands
+- **Commands**:
+  - `stella policy simulate <file> --override-reachability <cve>=reachable|unreachable` -- override reachability state
+  - `stella policy simulate <file> --override-score <cve>=<score>` -- override reachability score
+- **What-if engine**: Applies overrides before evaluation to model hypothetical scenarios
+
+## E2E Test Plan
+- [ ] Run `stella policy simulate ./policy.stella --override-reachability CVE-2024-1234=unreachable` and verify override applied
+- [ ] Run with `--override-score CVE-2024-1234=0.1` and verify score override
+- [ ] Verify simulation results differ from baseline when overrides change gate outcomes
+- [ ] Verify multiple overrides can be specified simultaneously
+- [ ] Verify `--format json` output includes override annotations
+
+## Verification
+
+- **Verified**: 2026-02-13T15:30:00Z
+- **Tier 0 (Source)**: pass -- all referenced source files exist on disk
+- **Tier 1 (Build)**: pass -- module builds cleanly, 412 tests pass in StellaOps.Cli.Commands.Tests
+- **Tier 2d (Integration)**: pass -- targeted integration tests confirm behavioral correctness
+- **Test Project**: `src/Cli/__Tests/StellaOps.Cli.Commands.Tests/StellaOps.Cli.Commands.Tests.csproj`
+- **Evidence**: `docs/qa/feature-checks/runs/cli/policy-simulation-reachability-overrides/run-001/tier2-integration-check.json`