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docs/features/checked/cli/delta-scan-cli-command.md

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+# Delta Scan CLI Command
+
+## Module
+Cli
+
+## Status
+VERIFIED
+
+## Description
+CLI command `stella scan delta --old <image> --new <image>` for delta scanning between container image versions. Supports JSON/text/summary output formats, exit codes for CVE status (0=clean, 1=new CVEs, 2=error), and flags for policy, platform, SBOM format, signing, Rekor submission, and timeout configuration.
+
+## Implementation Details
+- **Command Group**: `src/Cli/StellaOps.Cli/Commands/DeltaCommandGroup.cs` -- `DeltaCommandGroup` for `stella delta` / `stella scan delta` commands
+- **Commands**:
+  - `stella scan delta --old <image> --new <image>` -- delta scan between two image versions. Options: `--format json|text|summary`, `--policy <file>`, `--platform <arch>`, `--sbom-format cdx|spdx`, `--sign`, `--rekor`, `--timeout <duration>`
+- **Exit codes**: 0=no new CVEs, 1=new CVEs found, 2=error
+- **Integration**: Connects to Scanner module for diff computation
+
+## E2E Test Plan
+- [ ] Run `stella scan delta --old app:v1.0 --new app:v2.0` and verify delta scan results
+- [ ] Run with `--format json` and verify structured delta output
+- [ ] Run with `--format summary` and verify summary output
+- [ ] Verify exit code 0 when no new CVEs introduced
+- [ ] Verify exit code 1 when new CVEs found in new image
+- [ ] Run with `--sign --rekor` and verify signed results with Rekor entry
+- [ ] Run with `--policy ./policy.stella` and verify policy evaluation against delta
+- [ ] Verify `--timeout` flag works for long-running scans
+
+## 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/delta-scan-cli-command/run-001/tier2-integration-check.json`