diff --git a/specs/039-inventory-program/plan.md b/specs/039-inventory-program/plan.md
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+# Implementation Plan: Inventory Program (Meta)
+
+**Branch**: `feat/039-inventory-program` | **Date**: 2026-01-07 | **Spec**: `specs/039-inventory-program/spec.md`
+
+## Summary
+
+Program-level north star and decomposition for the Inventory-first roadmap.
+
+## Deliverables
+
+- A shared vocabulary and boundaries (Inventory vs Snapshot/Backup)
+- A roadmap to split delivery into 040–044 feature specs
+- Program principles aligned with constitution
+
+## Notes
+
+This spec is not tied to code changes.
diff --git a/specs/039-inventory-program/spec.md b/specs/039-inventory-program/spec.md
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+# Feature Specification: Inventory Program (Meta)
+
+**Feature Branch**: `feat/039-inventory-program`  
+**Created**: 2026-01-07  
+**Status**: Draft  
+
+## Purpose
+
+This is an epic/program-level specification that anchors vision, scope, principles, and a roadmap for an Inventory-first approach across TenantPilot.
+
+This document is intentionally non-implementation and does not require immediate code changes.
+
+## Program Goals
+
+- Establish Inventory as the primary substrate for analysis, reporting, monitoring, and UI navigation (Inventory is “last observed”, not absolute Intune truth).
+- Maintain immutable snapshots/backups as explicit actions (manual/scheduled), separate from inventory sync.
+- Provide a config-driven coverage/support matrix across policy types (backup/restore/risk/support).
+- Build toward dependency visibility, cross-tenant comparison/promotion, and drift detection.
+
+## Key Definitions
+
+- **Inventory**: TenantPilot’s last observed catalog of Intune objects (mutable; updated by sync runs).
+- **Snapshot/Backup**: Immutable capture of an object’s payload for versioning/restore (explicit action).
+- **Coverage/Support Matrix**: Derived view describing support level (backup/restore/risk) per policy type.
+
+## Data Domains
+
+- Inventory Items
+- Sync Runs (observability)
+- Support/Capabilities derived from contracts/config
+- Dependencies (links between inventory items and foundation objects)
+- Cross-tenant context (explicit and access-checked)
+
+## Principles (Program-level)
+
+- Inventory-first, snapshots-second
+- Read/write separation by default (preview + confirmation + audit + tests for writes)
+- Single contract path to Graph
+- Deterministic capabilities
+- Tenant isolation is non-negotiable
+- Automation is idempotent & observable (locks, run records, stable error codes)
+- Data minimization & safe logging
+
+## Roadmap / Decomposition
+
+- **Spec 040 — Inventory Core**: inventory items + sync runs + deterministic selection + missing semantics
+- **Spec 041 — Inventory UI**: inventory lists, coverage matrix, sync runs UI, policy viewer
+- **Spec 042 — Dependencies Graph**: inventory_links and dependency views (assignments/scope tags/filters first)
+- **Spec 043 — Cross-tenant Compare & Promotion**: read-only compare first; gated promotion later
+- **Spec 044 — Drift MVP**: drift findings based on inventory/run metadata and optional hashes
+
+## Non-Goals
+
+- This meta spec does not define concrete schemas or endpoints.
+- This meta spec does not introduce new write paths (promotion/remediation) without dedicated feature specs.
diff --git a/specs/039-inventory-program/tasks.md b/specs/039-inventory-program/tasks.md
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+# Tasks: Inventory Program (Meta)
+
+**Input**: `specs/039-inventory-program/spec.md`
+
+- [ ] T001 Confirm naming/numbering for 040–044
+- [ ] T002 Draft skeleton specs for 041–044
+- [ ] T003 Validate alignment with constitution principles
diff --git a/specs/040-inventory-core/plan.md b/specs/040-inventory-core/plan.md
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+# Implementation Plan: Inventory Core (040)
+
+**Branch**: `feat/040-inventory-core` | **Date**: 2026-01-07 | **Spec**: `specs/040-inventory-core/spec.md`
+
+## Summary
+
+Implement a tenant-scoped inventory catalog (“last observed”) and an observable sync run system with deterministic selection scoping. Ensure no snapshots/backups are created by sync.
+
+## Constitution Check
+
+- Inventory-first, snapshots-second (sync never creates snapshots)
+- Read/write separation (sync is read-only; any future writes require preview/confirmation/audit/tests)
+- Single contract path to Graph (Graph access only through existing abstractions/contracts)
+- Deterministic capabilities (capabilities resolver output testable)
+- Tenant isolation (non-negotiable)
+- Automation observable + idempotent (locks, run records, stable error codes, 429/503 handling)
+- Data minimization + safe logging
+
+## Deliverables (Phase-friendly)
+
+- Data model for inventory items and sync runs
+- Sync engine orchestration and locking strategy
+- Deterministic selection hashing
+- Capabilities resolver output snapshot tests
+- Minimal Filament/CLI surface to trigger and observe sync runs (if required by tasks)
+
+## Out of Scope
+
+- Dependency graph hydration (spec 042)
+- Cross-tenant promotion (spec 043)
+- Drift reporting (spec 044)
+- Lifecycle “deleted” semantics (feature 900)
diff --git a/specs/040-inventory-core/spec.md b/specs/040-inventory-core/spec.md
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+# Feature Specification: Inventory Core (Sync + Catalog)
+
+**Feature Branch**: `feat/040-inventory-core`  
+**Created**: 2026-01-07  
+**Status**: Draft  
+
+## Overview
+
+TenantPilot needs a reliable, tenant-scoped inventory catalog that represents what the system last observed in Microsoft Intune. This inventory is used as the primary substrate for analysis, reporting, monitoring, and UI visibility.
+
+**Key intent:** Inventory is a “last observed” catalog (TenantPilot’s truth), not an absolute truth about Intune completeness.
+
+**Non-goal:** A sync MUST NOT create snapshots or backups automatically.
+
+## User Scenarios & Testing *(mandatory)*
+
+### User Story 1 — Run Inventory Sync for a Tenant (Priority: P1)
+
+A tenant admin (or scheduled automation) runs an inventory sync for a tenant to populate/update the inventory catalog.
+
+**Why this priority**: Everything else depends on having a stable, queryable inventory catalog.
+
+**Independent Test**: Run a sync for a tenant and verify inventory items are upserted, tenant-scoped, and last-observed fields update without producing snapshots/backups.
+
+**Acceptance Scenarios**:
+
+1. **Given** a tenant and a configured selection of policy types/categories, **When** a sync completes, **Then** inventory items are upserted for each observed object with correct `tenant_id`, `policy_type`, `external_id`, and `last_seen_at`.
+2. **Given** an existing inventory item, **When** the same object is observed again, **Then** the existing record is updated (not duplicated) and `last_seen_at` and `last_seen_run_id` are updated.
+3. **Given** a sync selection that excludes some policy types/categories, **When** the sync completes, **Then** only objects within that selection are observed/updated.
+4. **Given** a successful sync, **When** the sync finishes, **Then** no policy snapshots/backups are created as a side effect.
+
+---
+
+### User Story 2 — Observe Completeness/Confidence of a Sync (Priority: P1)
+
+A tenant admin views whether missing items are likely “not seen” due to partial/failed sync vs confidently missing in a clean run.
+
+**Why this priority**: Prevents misleading conclusions (e.g., “deleted”) when Graph errors or permissions issues occur.
+
+**Independent Test**: Mark a run as partial/failed and verify missing items are presented as low confidence (derived at query/UI time) and do not imply deletion.
+
+**Acceptance Scenarios**:
+
+1. **Given** a `latestRun` for a tenant+selection that has `status != success` or `had_errors = true`, **When** inventory is queried for missing items relative to that run, **Then** missing is presented as low confidence (and no stronger claim is made).
+2. **Given** a `latestRun` for a tenant+selection that is `status = success` and `had_errors = false`, **When** an item was not observed in that run, **Then** the UI can show it as “not seen in latest run” (higher confidence) without implying deletion.
+
+---
+
+### User Story 3 — Monitor Sync Runs (Priority: P2)
+
+A tenant admin (and platform admin) can see sync run history and quickly diagnose failures using stable error codes and counts.
+
+**Why this priority**: Makes automation observable and supportable at MSP scale.
+
+**Independent Test**: Create sync runs with different statuses and verify run records include counts and stable error codes.
+
+**Acceptance Scenarios**:
+
+1. **Given** multiple sync runs, **When** a user views run history, **Then** each run shows status, started/finished timestamps, and counts (observed/updated/errors).
+2. **Given** a throttling event, **When** a sync run records it, **Then** the run captures a stable error code (e.g., “graph_throttled”) and does not fail silently.
+
+---
+
+### Edge Cases
+
+- Sync is triggered twice for the same tenant+selection while the first is still running.
+- Sync completes with partial results due to transient Graph errors.
+- A tenant’s permissions change between runs causing objects to be invisible.
+- Selection payload is equivalent but arrays are ordered differently.
+
+## Requirements *(mandatory)*
+
+### Functional Requirements
+
+- **FR-001**: System MUST maintain an Inventory Catalog that represents TenantPilot’s last observed state of Intune objects.
+- **FR-002**: System MUST upsert inventory items by a stable identity key that prevents duplicates.
+- **FR-003**: System MUST record Sync Runs with status, timestamps, counts, and stable error codes.
+- **FR-004**: System MUST ensure tenant isolation for all inventory and run queries.
+- **FR-005**: System MUST support deterministic selection scoping via `selection_hash` for sync runs.
+- **FR-006**: System MUST NOT create snapshots/backups during inventory sync (sync is not backup).
+- **FR-007**: System MUST derive “missing” as a computed state relative to the latest completed run for the same tenant+selection.
+- **FR-008**: System MUST enforce `meta_jsonb` key whitelisting by dropping unknown keys without failing the sync.
+- **FR-009**: System MUST implement safe automation behavior: locking, idempotency, and observable failures.
+
+### Non-Functional Requirements
+
+- **NFR-001 (Concurrency limits)**: Sync automation MUST enforce two limits: a global concurrency limit (across tenants) and a per-tenant concurrency limit.
+- **NFR-002 (Throttling resilience)**: Sync MUST handle throttling/transient failures (e.g., 429/503) using backoff + jitter.
+- **NFR-003 (Deterministic behavior)**: Selection hashing and capability derivation MUST be deterministic and testable.
+- **NFR-004 (Data minimization)**: Inventory MUST store metadata and whitelisted meta only; payload-heavy content belongs to snapshots/backups.
+- **NFR-005 (Safe logging)**: Logs MUST not contain secrets/tokens; monitoring MUST rely on run records + error codes.
+
+### Key Entities *(include if feature involves data)*
+
+- **Inventory Item**: A tenant-scoped record representing a single Intune object as last observed (type, external identity, display name/metadata, last observed fields, whitelisted meta).
+- **Sync Run**: A tenant-scoped record representing an inventory sync execution for a specific selection (selection_hash, status, timestamps, counts, stable error codes).
+- **Selection Payload**: The normalized representation of the run scope used to compute selection_hash.
+
+## Success Criteria *(mandatory)*
+
+### Measurable Outcomes
+
+- **SC-001**: For a given tenant, inventory sync can be executed repeatedly without creating duplicate inventory items.
+- **SC-002**: A sync run always produces a run record with status, timestamps, and counts.
+- **SC-003**: Missing is computed relative to latest completed run for the same tenant+selection; runs with different selection hashes do not affect each other.
+- **SC-004**: Unknown meta keys never break sync and are not persisted.
+- **SC-005**: Operators can distinguish “not seen” from “deleted” (deleted is reserved and not produced in this feature).
+
+## Spec Appendix: Deterministic Selection + Missing Semantics (copy/paste-ready)
+
+### Definition: “completed” and “latestRun”
+
+- **Definition:** `completed` means `status ∈ {success, partial, failed, skipped}` and `finished_at != null` (or the equivalent field used by the run model).
+- **Definition:** `latestRun` is the latest completed Sync Run for `(tenant_id, selection_hash)`.
+
+### Selection Hash
+
+- `selection_payload` includes only fields that influence run scope:
+  - `policy_types[]`, `categories[]`, `include_foundations` (bool), `include_dependencies` (bool)
+- `canonical_json(payload)` is a canonical JSON serialization with:
+  - sorted object keys
+  - sorted arrays for `policy_types` and `categories`
+  - no whitespace / pretty formatting
+- `selection_hash = sha256(canonical_json(selection_payload))`
+- **AC:** Identical selection payload ⇒ identical selection_hash (independent of array ordering).
+
+### Missing is derived (not persisted)
+
+- **Definition:** Missing is a derived state computed at query/UI time relative to `latestRun(tenant_id, selection_hash)`.
+- **AC:** Runs with different `selection_hash` do not affect missing computation for other selections.
+- If `latestRun.status != success` or `latestRun.had_errors = true`, items not observed in that run are presented as `missing (low confidence)`.
+
+### Deleted is reserved
+
+- `deleted` is reserved and MUST NOT be produced by this feature.
+- Only a later lifecycle feature may set `deleted` with strict verification rules.
+
+### Meta Whitelist (Fail-safe)
+
+- `meta_jsonb` has a documented whitelist of allowed keys.
+- **AC:** Unknown `meta_jsonb` keys are dropped (not persisted) and MUST NOT cause sync to fail.
+
+### Observed Run
+
+- `inventory_items.last_seen_run_id` and `inventory_items.last_seen_at` are updated when an item is observed.
+- `last_seen_run_id` implies the selection via `sync_runs.selection_hash`; no per-item selection hash is required for core.
+
+## Testing Guidance (non-implementation)
+
+These are test cases expressed in behavior terms (not code).
+
+### Test Cases — Sync and Upsert
+
+- **TC-001**: Sync creates or updates inventory items and sets `last_seen_at`.
+- **TC-002**: Re-running sync for the same tenant+selection updates existing records and does not create duplicates.
+- **TC-003**: Inventory queries scoped to Tenant A never return Tenant B’s items.
+
+### Test Cases — Selection Hash Determinism
+
+- **TC-010**: Same selection payload with arrays in different order yields the same selection_hash.
+- **TC-011**: Different selection payload yields a different selection_hash.
+
+### Test Cases — Missing Semantics
+
+- **TC-020**: Missing is derived relative to latest completed run for the same tenant+selection.
+- **TC-021**: A run for selection Y does not affect missing computation for selection X.
+- **TC-022**: If latestRun is partial/failed or had_errors, missing is shown as low confidence.
+
+### Test Cases — Meta Whitelist
+
+- **TC-030**: Unknown meta keys are not persisted and do not fail sync.
+
+### Test Cases — Automation Safety
+
+- **TC-040**: Concurrent sync triggers for the same tenant+selection do not result in overlapping runs (lock behavior).
+- **TC-041**: A throttling event results in a visible, stable error code and a non-silent failure signal.
diff --git a/specs/040-inventory-core/tasks.md b/specs/040-inventory-core/tasks.md
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+# Tasks: Inventory Core (040)
+
+**Input**: `specs/040-inventory-core/spec.md`, `specs/040-inventory-core/plan.md`
+
+## P1 — MVP (US1/US2)
+
+- [ ] T001 [US1] Define Inventory Item data model (tenant-scoped identity + last_seen fields)
+- [ ] T002 [US1] Define Sync Run data model (tenant_id, selection_hash, status, timestamps, counts, stable error codes)
+- [ ] T003 [US1] Implement deterministic selection hashing (canonical json + sha256)
+- [ ] T004 [US1] Implement inventory upsert semantics (no duplicates)
+- [ ] T005 [US1] Enforce tenant isolation in all inventory/run queries
+- [ ] T006 [US2] Implement derived “missing” computation relative to latest completed run (tenant_id + selection_hash)
+- [ ] T007 [US2] Ensure low-confidence missing when latestRun is partial/failed or had_errors
+- [ ] T008 [US2] Implement meta_jsonb whitelist enforcement (drop unknown keys, never fail sync)
+
+## P2 — Observability & Safety (US3 + NFR)
+
+- [ ] T009 [US3] Ensure run records include stable error codes and counts
+- [ ] T010 [NFR] Add idempotency + locks to prevent overlapping runs per tenant+selection
+- [ ] T011 [NFR] Add global + per-tenant concurrency limiting strategy
+- [ ] T012 [NFR] Implement throttling handling strategy (backoff + jitter for transient Graph failures)
+
+## Tests (Required for runtime behavior)
+
+- [ ] T020 [US1] Tests: upsert does not create duplicates; last_seen updated
+- [ ] T021 [US2] Tests: missing derived per latestRun(selection_hash); selection isolation
+- [ ] T022 [US2] Tests: partial/failed run => low confidence missing
+- [ ] T023 [US2] Tests: meta whitelist drops unknown keys without failing
+- [ ] T024 [NFR] Tests: selection_hash determinism (array ordering)
+
+## Notes
+
+- “deleted” is reserved and MUST NOT be produced in this feature.
diff --git a/specs/041-inventory-ui/plan.md b/specs/041-inventory-ui/plan.md
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+# Implementation Plan: Inventory UI
+
+**Date**: 2026-01-07  
+**Spec**: `specs/041-inventory-ui/spec.md`
+
+## Summary
+
+Add admin screens for inventory browsing, item inspection, sync run visibility, and type coverage/capabilities.
+
+## Dependencies
+
+- Inventory core data + sync runs available (Spec 040)
+- Capabilities/support matrix derivation available
+
+## Deliverables
+
+- Inventory landing + list + detail
+- Sync runs list + detail
+- Coverage/capabilities view
+
+## Risks
+
+- UI performance for large tenants
+- Data leakage if raw payload rendering is not constrained
diff --git a/specs/041-inventory-ui/spec.md b/specs/041-inventory-ui/spec.md
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+# Feature Specification: Inventory UI
+
+**Feature Branch**: `feat/041-inventory-ui`  
+**Created**: 2026-01-07  
+**Status**: Draft  
+
+## Purpose
+
+Provide a consistent admin UI for browsing Inventory, understanding sync status, and seeing capability/coverage information per policy type.
+
+## Users
+
+- Tenant Admin (primary)
+- MSP Operator (if cross-tenant access exists; read-only unless explicitly allowed)
+
+## User Scenarios & Testing
+
+### Scenario 1: Browse inventory
+- Given a tenant context
+- When the user opens Inventory
+- Then they can browse inventory items by type and see core fields (name, platform/type, last observed, status)
+
+### Scenario 2: Inspect a single inventory item
+- Given an inventory item exists
+- When the user opens the item details
+- Then they can see normalized metadata and the latest observed payload (or a safe subset if full payload is not available)
+
+### Scenario 3: See sync run outcomes
+- Given sync runs exist
+- When the user opens Sync Runs
+- Then they can see run status, timing, counts, and error summaries
+
+### Scenario 4: Understand coverage/capabilities
+- Given the system has a support matrix
+- When the user views the coverage table
+- Then they can see which types are supported for backup/restore/preview and any restrictions
+
+## Functional Requirements
+
+- FR1: Provide an Inventory landing view scoped to the current tenant.
+- FR2: Provide inventory list views grouped by policy type (or category) with pagination/search.
+- FR3: Provide an inventory item detail view showing:
+  - stable identifiers
+  - last observed timestamps
+  - source run reference
+  - capability/support status for the item’s type
+- FR4: Provide a Sync Runs list/detail view.
+- FR5: Provide a Coverage/Capabilities view derived from configuration/contract registry.
+- FR6: Enforce tenant isolation in all navigation and data access.
+
+## Non-Functional Requirements
+
+- NFR1: Pages should remain usable for tenants with large inventories (no full-table loads).
+- NFR2: UI must not expose secrets or unsafe payload fields.
+- NFR3: Errors should be actionable (clear messages + stable error codes where available).
+
+## Success Criteria
+
+- SC1: Admins can find an inventory item and view its details in under 60 seconds.
+- SC2: Admins can identify the latest completed sync run for a tenant in under 30 seconds.
+- SC3: Coverage view communicates support level clearly enough that admins make the correct decision without trial-and-error.
+
+## Out of Scope
+
+- Writing changes back to Intune from inventory screens (restore/promotion).
+- Cross-tenant comparison (covered in Spec 043).
+
+## Related Specs
+
+- Program: `specs/039-inventory-program/spec.md`
+- Core: `specs/040-inventory-core/spec.md`
diff --git a/specs/041-inventory-ui/tasks.md b/specs/041-inventory-ui/tasks.md
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+# Tasks: Inventory UI
+
+- [ ] T001 Inventory landing page + navigation
+- [ ] T002 Inventory list views per type/category
+- [ ] T003 Inventory detail view with capability/support indicator
+- [ ] T004 Sync runs list + detail
+- [ ] T005 Coverage/capabilities view derived from config/contracts
+- [ ] T006 Authorization + tenant isolation tests
+- [ ] T007 Performance sanity checks (pagination/search)
diff --git a/specs/042-inventory-dependencies-graph/plan.md b/specs/042-inventory-dependencies-graph/plan.md
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+# Implementation Plan: Inventory Dependencies Graph
+
+**Date**: 2026-01-07  
+**Spec**: `specs/042-inventory-dependencies-graph/spec.md`
+
+## Summary
+
+Add dependency edge model, extraction logic, and UI views to explain relationships between inventory items and prerequisite/foundation objects.
+
+## Dependencies
+
+- Inventory items and stable identifiers (Spec 040)
+- Inventory UI detail pages (Spec 041) or equivalent navigation
+
+## Deliverables
+
+- Relationship taxonomy
+- Persisted dependency edges
+- Query and rendering in UI
+
+## Risks
+
+- Heterogeneous reference shapes across policy types
+- Edge explosion for large tenants
diff --git a/specs/042-inventory-dependencies-graph/spec.md b/specs/042-inventory-dependencies-graph/spec.md
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+# Feature Specification: Inventory Dependencies Graph
+
+**Feature Branch**: `feat/042-inventory-dependencies-graph`  
+**Created**: 2026-01-07  
+**Status**: Draft  
+
+## Purpose
+
+Represent and surface dependency relationships between inventory items and foundational Intune objects so admins can understand blast radius and prerequisites.
+
+## User Scenarios & Testing
+
+### Scenario 1: View dependencies for an item
+- Given an inventory item
+- When the user opens its dependencies view
+- Then they can see inbound and outbound relationships (e.g., “uses”, “assigned to”, “scoped by”)
+
+### Scenario 2: Identify missing prerequisites
+- Given an item references a prerequisite object not present in inventory
+- When the user views dependencies
+- Then missing prerequisites are clearly indicated
+
+### Scenario 3: Filter dependencies by relationship type
+- Given multiple relationship types exist
+- When the user filters by relationship type
+- Then only matching edges are shown
+
+## Functional Requirements
+
+- FR1: Define a normalized set of relationship types.
+- FR2: Store dependency edges between inventory items and other objects (including non-inventory foundations when applicable).
+- FR3: Allow querying inbound/outbound edges for a given item.
+- FR4: Show missing prerequisites without requiring a separate “deleted” state in core inventory.
+- FR5: All dependency data is tenant-scoped and access-controlled.
+
+## Non-Functional Requirements
+
+- NFR1: Dependency extraction must be idempotent (re-runnable without duplicating edges).
+- NFR2: Dependency extraction must not fail an inventory sync run if an unknown/unsupported reference is encountered; it should record a safe warning.
+
+## Success Criteria
+
+- SC1: Admins can determine prerequisites and blast radius for an item in under 2 minutes.
+- SC2: For supported relationship types, dependency edges are consistent across re-runs (deterministic output).
+
+## Out of Scope
+
+- Automatic remediation.
+- Cross-tenant dependency graphs.
+
+## Related Specs
+
+- Program: `specs/039-inventory-program/spec.md`
+- Core: `specs/040-inventory-core/spec.md`
diff --git a/specs/042-inventory-dependencies-graph/tasks.md b/specs/042-inventory-dependencies-graph/tasks.md
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+# Tasks: Inventory Dependencies Graph
+
+- [ ] T001 Define relationship taxonomy
+- [ ] T002 Add dependency edge storage and indexes
+- [ ] T003 Extraction pipeline (idempotent)
+- [ ] T004 Item-level dependencies UI
+- [ ] T005 Tests for edge determinism and tenant scoping
diff --git a/specs/043-cross-tenant-compare-and-promotion/plan.md b/specs/043-cross-tenant-compare-and-promotion/plan.md
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+# Implementation Plan: Cross-tenant Compare and Promotion
+
+**Date**: 2026-01-07  
+**Spec**: `specs/043-cross-tenant-compare-and-promotion/spec.md`
+
+## Summary
+
+Introduce read-only cross-tenant comparison views; optionally add promotion with strong safety gates.
+
+## Dependencies
+
+- Inventory core + UI (Specs 040–041)
+- Strong authorization model for multi-tenant access
+
+## Deliverables
+
+- Tenant selection + comparison view
+- Safe diff output and export
+- (Optional) gated promotion workflow
+
+## Risks
+
+- Data leakage across tenants
+- Over-scoping promotion beyond safe MVP
diff --git a/specs/043-cross-tenant-compare-and-promotion/spec.md b/specs/043-cross-tenant-compare-and-promotion/spec.md
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+# Feature Specification: Cross-tenant Compare and Promotion
+
+**Feature Branch**: `feat/043-cross-tenant-compare-and-promotion`  
+**Created**: 2026-01-07  
+**Status**: Draft  
+
+## Purpose
+
+Enable safe cross-tenant comparison of inventory and, optionally, controlled promotion workflows.
+
+Comparison is read-only by default. Any write/promotion behavior must be explicitly gated, audited, and separately authorized.
+
+## User Scenarios & Testing
+
+### Scenario 1: Compare two tenants (read-only)
+- Given the operator has access to Tenant A and Tenant B
+- When they select two tenants and a set of policy types
+- Then they can see differences in presence and key metadata
+
+### Scenario 2: Compare with a stable reference
+- Given a reference selection scope
+- When the operator runs comparison
+- Then results are stable and reproducible for that scope
+
+### Scenario 3: Promotion is explicitly gated (optional)
+- Given promotion is enabled by policy
+- When the operator initiates promotion
+- Then the system requires explicit confirmation and records an audit event
+
+## Functional Requirements
+
+- FR1: Support selecting two tenants within authorized scope.
+- FR2: Provide read-only diff views based on inventory metadata and stable identifiers.
+- FR3: Provide exportable comparison results.
+- FR4: If promotion is included:
+  - require explicit enablement
+  - require explicit confirmation per operation
+  - record audit logs
+  - support dry-run/preview
+
+## Non-Functional Requirements
+
+- NFR1: Enforce tenant isolation and least privilege across tenant selection and data access.
+- NFR2: Comparison must not expose secrets or unsafe payload fields.
+
+## Success Criteria
+
+- SC1: Operators can identify which tenant differs for a given policy type in under 2 minutes.
+- SC2: Read-only comparisons are reproducible when run again with the same scope.
+
+## Out of Scope
+
+- Bulk remediation without preview/confirmation.
+
+## Related Specs
+
+- Program: `specs/039-inventory-program/spec.md`
+- Core: `specs/040-inventory-core/spec.md`
+- Drift: `specs/044-drift-mvp/spec.md`
diff --git a/specs/043-cross-tenant-compare-and-promotion/tasks.md b/specs/043-cross-tenant-compare-and-promotion/tasks.md
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+# Tasks: Cross-tenant Compare and Promotion
+
+- [ ] T001 Define authorized tenant selection rules
+- [ ] T002 Read-only compare UI and diff rules
+- [ ] T003 Export capability for comparison results
+- [ ] T004 If enabled: promotion workflow with preview + confirm + audit
+- [ ] T005 Tests: tenant isolation, authorization, reproducibility
diff --git a/specs/044-drift-mvp/plan.md b/specs/044-drift-mvp/plan.md
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+# Implementation Plan: Drift MVP
+
+**Date**: 2026-01-07  
+**Spec**: `specs/044-drift-mvp/spec.md`
+
+## Summary
+
+Add drift findings generation and UI using inventory and sync run metadata.
+
+## Dependencies
+
+- Inventory core + run tracking (Spec 040)
+- Inventory UI patterns (Spec 041)
+
+## Deliverables
+
+- Baseline definition and drift finding generation
+- Drift summary + detail UI
+- Acknowledge/triage actions
+
+## Risks
+
+- False positives if baseline definition is unclear
+- Data volume for large tenants
diff --git a/specs/044-drift-mvp/spec.md b/specs/044-drift-mvp/spec.md
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+# Feature Specification: Drift MVP
+
+**Feature Branch**: `feat/044-drift-mvp`  
+**Created**: 2026-01-07  
+**Status**: Draft  
+
+## Purpose
+
+Detect and report drift between expected and observed states using inventory and run metadata.
+
+This MVP focuses on reporting and triage, not automatic remediation.
+
+## User Scenarios & Testing
+
+### Scenario 1: View drift summary
+- Given inventory sync has run at least twice
+- When the admin opens Drift
+- Then they see a summary of changes since the last baseline
+
+### Scenario 2: Drill into a drift finding
+- Given a drift finding exists
+- When the admin opens the finding
+- Then they see what changed, when, and which run observed it
+
+### Scenario 3: Acknowledge/triage
+- Given a drift finding exists
+- When the admin marks it acknowledged
+- Then it is hidden from “new” lists but remains auditable
+
+## Functional Requirements
+
+- FR1: Define a baseline concept (e.g., last completed run for a selection scope).
+- FR2: Produce drift findings for adds/removals/metadata changes based on inventory/run state.
+- FR3: Provide drift UI with summary and details.
+- FR4: Allow acknowledgement/triage states.
+
+## Non-Functional Requirements
+
+- NFR1: Drift generation must be deterministic for the same baseline and scope.
+- NFR2: Drift must remain tenant-scoped and safe to display.
+
+## Success Criteria
+
+- SC1: Admins can identify drift across supported types in under 3 minutes.
+- SC2: Drift results are consistent across repeated generation for the same baseline.
+
+## Out of Scope
+
+- Automatic revert/promotion.
+
+## Related Specs
+
+- Program: `specs/039-inventory-program/spec.md`
+- Core: `specs/040-inventory-core/spec.md`
+- Compare: `specs/043-cross-tenant-compare-and-promotion/spec.md`
diff --git a/specs/044-drift-mvp/tasks.md b/specs/044-drift-mvp/tasks.md
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+# Tasks: Drift MVP
+
+- [ ] T001 Define baseline and scope rules
+- [ ] T002 Drift finding generation (deterministic)
+- [ ] T003 Drift summary + detail UI
+- [ ] T004 Acknowledge/triage state
+- [ ] T005 Tests for determinism and tenant scoping