Desktop sessions need a fast local escape hatch that opens the same materialized cwd the agent is editing, without showing unavailable IDE choices or persisting detection state. This adds a local open-targets API with silent in-memory detection for common IDEs and platform file managers, then wires a compact Codex-style toolbar menu into the desktop TabBar for active session workdirs.
Constraint: The first version is local IDE/editor and Finder/Explorer/file-manager only, no terminal targets or IDE plugin integration.
Constraint: The opened path must come from the active session workDir so isolated worktrees open the actual agent editing surface.
Rejected: Persisting detected applications | detection is cheap and temporary state avoids stale app inventory.
Rejected: Rendering unavailable IDEs as disabled menu rows | the user asked to show only detected targets and fall back to Finder/Explorer when no IDE is available.
Confidence: high
Scope-risk: moderate
Directive: Keep this path session-workdir based; do not switch it to repository root without proving isolated worktree behavior.
Tested: bun test src/server/__tests__/open-target-service.test.ts src/server/__tests__/open-target-api.test.ts
Tested: cd desktop && bun run test -- src/stores/openTargetStore.test.ts src/components/layout/OpenProjectMenu.test.tsx src/components/layout/TabBar.test.tsx
Tested: cd desktop && bun run lint
Tested: bun run check:desktop
Tested: bun test src/server/__tests__/h5-access-auth.test.ts -t 'allows local desktop H5 access settings under explicit server auth with a valid bearer'
Not-tested: bun run check:server full suite had one unrelated H5 auth integration timeout in the full concurrent run; the timed-out test passed when rerun alone.
