# Reachability overlays

Purpose
- Present reachability states on SBOM and vulnerability views with evidence-backed badges.

Overlay states
- Reachable, conditionally_reachable, unreachable, unknown.
- State mapping follows the reachability lattice and evidence schemas.

Evidence sources
- Static analysis evidence (callgraph and symbol data).
- Runtime evidence (entry traces and runtime hits).
- Edge bundle evidence when provided by attested bundles.

UI behavior
- Badges include state, evidence source, and last evaluation timestamp.
- Timeline view shows state transitions and evidence hashes.
- Overlays are included in saved views and exports.

Accessibility and offline
- Keyboard shortcuts toggle overlays and open evidence drawers.
- Offline mode shows snapshot staleness and disables live verification.

Related references
- architecture/reachability-lattice.md
- architecture/reachability-evidence.md
- ui/sbom-graph-explorer.md
- ui/vulnerability-explorer.md