Date: 2026-03-17 Status: Planning / handoff pack Scope: Dependency-ordered backlog for Navigator as a projection surface over graph truth and workbench arrangement state.

Related docs:

• NAVIGATOR.md — Navigator domain spec and authority boundaries
• navigator_interaction_contract.md — canonical Navigator click grammar and graph/workbench resolution rules
• navigator_projection_spec.md — canonical projection pipeline, composition, annotation, and diff contract
• ../../../archive_docs/checkpoint_2026-04-23/graphshell_docs/implementation_strategy/navigator/2026-04-21_navigator_projection_pipeline_plan.md — archived producing plan and projection-pipeline findings
• ../../technical_architecture/graphlet_model.md — canonical graphlet semantics consumed by Navigator projection
• ../../technical_architecture/domain_interaction_scenarios.md — canonical cross-domain scenario IDs (DI01-DI06)
• ../domain_interaction_acceptance_matrix.md — compact review matrix for cross-domain scenario evidence
• ../workbench/WORKBENCH.md — workbench domain ownership and arrangement authority
• ../workbench/graph_first_frame_semantics_spec.md — graph/workbench frame semantics
• ../graph/graph_backlog_pack.md — graph-side backlog dependencies used by Navigator projections

• Hub issue: #306 (Hub: five-domain architecture adoption — Shell host, graphlet model, cross-domain scenarios)
• Primary implementation issue: #304 (Adopt the canonical graphlet model across Navigator and Workbench)
• Review/evidence issue: #305 (Operationalize cross-domain scenario IDs and acceptance evidence)

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Confirmed slices now landed in code:

• ✅ Navigator intent surface canonicalization: active reducer/view-action paths use SetNavigator* and RebuildNavigatorProjection; legacy SetFileTree* and RebuildFileTreeProjection paths are removed. Advances: NV01, NV06.
• ✅ Containment projection source is now graph-backed from ContainmentRelation edges. Advances: NV04, NV18.
• ✅ Projection refresh now triggers from graph deltas affecting containment (node add/remove and URL updates). Advances: NV10.

These deltas are partial closures and should be referenced when preparing the full milestone closure receipt (NV25).

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1. NV01 Navigator Projection Boundary. Depends: none. Done gate: one canonical doc defines Navigator as a projection surface, not its own truth store.
2. NV02 Navigator Row-Type Inventory. Depends: NV01. Done gate: every row type is listed and tagged as node, frame, tile, section, family, or derived structural row.
3. NV03 Navigator Row Identity Contract. Depends: NV02. Done gate: every Navigator row has a stable identity source and no ad hoc ephemeral row IDs remain.
4. NV04 Navigator Section Mapping Audit. Depends: NV01, NV02. Done gate: each section is mapped to graph truth, relation-family projection, workbench projection, or recency projection.
5. NV05 Navigator Expansion State Contract. Depends: NV03, NV04. Done gate: expansion/collapse state is defined as projection/session state with persistence rules.
6. NV06 Navigator Click Grammar Lock. Depends: NV02, NV04. Done gate: row-type-specific single-click and double-click behavior is canonical.
7. NV07 Navigator Selection Contract. Depends: NV03, NV06. Done gate: selection behavior maps cleanly onto the global mixed-selection model.
8. NV08 Navigator Residency-Aware Navigation Contract. Depends: NV06, NV07. Done gate: double-click routes differently for live versus cold nodes and is documented in carrier terms.
9. NV09 Navigator Structural Row Focus Rule. Depends: NV06, NV07. Done gate: structural rows expand/collapse and become command focus without pretending to be nodes.
10. NV10 Navigator Projection Refresh Triggers. Depends: NV01, NV04. Done gate: graph, workbench, and state changes that refresh Navigator are routed through shared signals, not ad hoc observers.

1. NV11 Navigator Reveal Rule. Depends: NV07, NV08. Done gate: reveal-on-select only happens when the graph is visible and the selected node is offscreen.
2. NV12 Navigator Multi-Selection Semantics. Depends: NV07. Done gate: Ctrl+Click, range/toggle behavior, and row focus rules are explicit.
3. NV13 Navigator Command Applicability Audit. Depends: NV07, NV12. Done gate: navigator-invoked commands obey the same "valid for every selected object" rule.
4. NV14 Navigator Recents Contract. Depends: NV04, NV08. Done gate: Recent is a recency-sorted projection with clear entry/exit semantics.
5. NV15 Navigator Arrangement Projection Contract. Depends: NV04, NV09. Done gate: frames, tiles, and canonically defined graphlets project consistently as expandable arrangement objects.
6. NV16 Navigator Search / Filter Model. Depends: NV04, NV10. Done gate: local filter/search semantics are explicit and do not mutate underlying truth.
7. NV17 Navigator Dismiss / Open Actions Audit. Depends: NV06, NV13. Done gate: Navigator row actions route through graph/workbench carriers instead of direct callsites.
8. NV18 Navigator Edge / Relation Surfacing Policy. Depends: NV04, NV15. Done gate: relation families shown in Navigator are explicit and tied to shared graph relation-family rules.
9. NV19 Navigator Empty / Degraded State Contract. Depends: NV10, NV16. Done gate: no-data, filtered-empty, and projection-error states are distinct and diagnosable.
10. NV20 Navigator Accessibility and Keyboard Model. Depends: NV03, NV06, NV12. Done gate: keyboard navigation, row focus, expand/collapse, and activate are specified.

1. NV21 Navigator Diagnostics Pack. Depends: NV10, NV19, NV20. Done gate: invalid row targets, stale projection entries, and routing failures emit diagnostics.
2. NV22 Navigator Scenario Test Matrix. Depends: NV06-NV21. Done gate: tests/spec scenarios cover row-type clicks, selection, reveal, recents, search/filter, and arrangement rows.
3. NV23 Workbench-Navigator Contract Sync Pass. Depends: WB25, NV22. Done gate: workbench pane/focus semantics and Navigator projection semantics no longer contradict each other.
4. NV24 Graph-Navigator Contract Sync Pass. Depends: NV04, NV18, graph backlog equivalents. Done gate: Navigator sections and graph relation/view semantics align.
5. NV24A Graph Overview Host-Form Contract. Depends: NV15, NV20, NV24. Done gate: the first graph-overview Navigator host is explicitly list-first in sidebars, optional-swatch gating is defined by host geometry, and toolbar hosts degrade to compact strips/counters rather than minimap semantics.
6. NV24B Graph Overview Projection Density + Filters. Depends: NV18, NV24A. Done gate: archived graph views are hidden by default behind an explicit filter toggle, dense inter-view relationships degrade to aggregated hints, and overview-projection state remains distinct from graph truth.
7. NV24C Graph Overview Routing Parity. Depends: NV17, NV24A, graph backlog equivalents. Done gate: focus/reveal actions route identically across toolbar and sidebar hosts, while structural editing hands off to the graph-owned Overview Plane rather than mutating Navigator-local state.
8. NV24D Navigator Annotation Registry Contract. Depends: NV18, NV20, NV24. Done gate: NodeAnnotation registry contributions, density classes, and cost/budget rules are canonical and row rendering no longer hard-codes every badge family.
9. NV24E Navigator Portal Gesture Contract. Depends: NV11, NV17, NV24. Done gate: Locate, Reveal-in-place, and Lift are named, routed through graph/workbench intents, and do not contradict reducer-only mutation rules.
10. NV24F Navigator Projection Diff Contract. Depends: NV10, NV20, NV24. Done gate: projection switches and refresh-trigger reruns animate via canonical diff identity and timing rules instead of teleporting rows.
11. NV24G Navigator Time-Axis Projection Contract. Depends: NV10, NV14, NV24. Done gate: time-axis is specified as a specialty projection consuming mixed_timeline_entries, with host-local cursor semantics and composition rules.
12. NV24H Navigator Layout Inheritance Contract. Depends: NV15, NV24A, NV24C. Done gate: every projection declares own, canvas, or canvas-compressed layout inheritance so host rendering and canvas-derived updates do not guess.
13. NV24I Navigator Projection Cost Classification. Depends: NV10, NV24D, NV24H. Done gate: every projection and annotation contributor declares live, debounced, or on-demand behavior plus any incremental-update requirement.
14. NV25 Navigator Milestone Closure Receipt. Depends: NV01-NV24, NV24A-NV24I. Done gate: one closure doc states what another agent can now safely build on for sections, click grammar, routing, and projection behavior.

• NV01 maps to the pipeline boundary and the rule that Navigator is projection-and-routing only.
• NV04 maps to stage 1 Scope and section/source alignment.
• NV10 maps to refresh-trigger routing for projection reruns.
• NV14 maps to recency-scored projections and declared cost class.
• NV15 maps to arrangement-backed scopes, graphlets, and layout inheritance.
• NV18 maps to relation surfacing through annotation, not silent suppression.
• NV24A-NV24C map to host-specific presentation and overview-swatch behavior.
• NV24D-NV24I cover the missing pipeline-wide primitives introduced by navigator_projection_spec.md.

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• NVS01 DI01 Graph-first local exploration parity. Depends: NV06, NV10, NV16. Done gate: selection -> ego graphlet -> frontier transition flow is implemented or evidenced without Navigator absorbing graph truth.
• NVS02 DI02 Corridor transition parity. Depends: NV08, NV18, NV24. Done gate: anchor selection -> corridor graphlet -> graph/path emphasis flow is coherent and evidenced against the canonical scenario.
• NVS03 DI05 Shell overview graphlet reorientation handoff. Depends: NV17, NV21, NV23. Done gate: a Shell overview handoff back into Navigator graphlet context is explicit, routed, and diagnosable.
• NVS04 Graph Overview swatch-to-plane handoff parity. Depends: NV24A, NV24B, NV24C. Done gate: compact Navigator overview surfaces orient and route successfully without pretending to be the full graph-view editor, and the handoff into Overview Plane is explicit and testable.

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Captured from implementation session. These are concrete code-level drift points where the live code does not match the chrome scope split spec.

Spec says (subsystem_ux_semantics/2026-03-13_chrome_scope_split_plan.md §5.1): "Disallowed here as primary command ownership: Back / Forward / Reload / StopLoad, Find in page, Content zoom controls, Compat / backend toggle."

Code does: workbench_host.rs:2281-2288 calls render_navigation_buttons() which renders Back/Forward/Reload/StopLoad/ZoomIn/ZoomOut/ZoomReset buttons, all dispatched via toolbar_routing::run_nav_action().

Fix: Delete render_navigation_buttons() (lines 3528-3629) and its call site (lines 2281-2288).

Spec says: Navigator host projects read-only status badges only, not actionable viewer state.

Code does: render_workbench_host() takes focused_content_status: &FocusedContentStatus (line 1802) and location_dirty: &mut bool (line 1803). Both are ONLY consumed by render_navigation_buttons(). No other code in the function reads them.

Fix: Remove both parameters from render_workbench_host() signature and from the call site in toolbar_dialog.rs.

Code has: use toolbar_routing::{self, ToolbarNavAction} (line 30) and use gui_state::FocusedContentStatus (line 28). Both become unused after removing render_navigation_buttons.

Fix: Remove both import lines.

Spec says (chrome_scope_split_plan.md §6, line 422): the struct still lists pub nav: PaneNavState.

Code does: The real WorkbenchChromeProjection (workbench_host.rs:262-278) does NOT have a nav field — it was never implemented. The spec-only field contradicts the updated §5.1 disallowed-controls list.

Fix: Remove pub nav: PaneNavState from the spec struct. The focused_pane_status: Vec<PaneStatusBadge> field (lines 423-425) already covers read-only badges and is the correct replacement.

Spec says: "Back/Forward/Reload live in the workbench-scoped host, not in the graph-scoped host" — this is the OLD model.

Should say: "Back/Forward/Reload live in tile chrome, not in any Navigator host."

Fix: Update line 750 to match the tile-chrome-only model.

Spec says (pane_chrome_and_promotion_spec.md §2): pane tree should reflect presentation mode (Floating/Docked/Tiled) with graduated row actions.

Code does: WorkbenchPaneEntry (workbench_host.rs:229-239) has no presentation_mode field. All pane rows render identically.

Fix: Add pub(crate) presentation_mode: PanePresentationMode to WorkbenchPaneEntry. Populate from NodePaneState.presentation_mode during pane_entry_for_tile(). Default to PanePresentationMode::Tiled for graph and tool panes.

1. Delete render_navigation_buttons() (workbench_host.rs:3528-3629) and call site (lines 2281-2288). The render_frame_pin_controls call at line 2289 remains.
2. Remove focused_content_status and location_dirty from render_workbench_host() signature; remove corresponding args from gui_frame/toolbar_dialog.rs call site.
3. Remove dead imports (FocusedContentStatus, toolbar_routing/ToolbarNavAction).
4. Add pub(crate) presentation_mode: PanePresentationMode to WorkbenchPaneEntry; populate in pane_entry_for_tile().
5. Spec fixes in chrome_scope_split_plan.md: remove pub nav: PaneNavState; update §12 line 750; add presentation_mode to WorkbenchTreeRow.

Verification: cargo check + cargo test --lib -- --quiet clean.