From 361e301f6706607db8b60da46ce2b034f35dd347 Mon Sep 17 00:00:00 2001
From: ahmido <ad88cgn@gmail.com>
Date: Sat, 10 Jan 2026 00:20:14 +0000
Subject: [PATCH] feat/042-inventory-dependencies-graph (#49)
MIME-Version: 1.0
Content-Type: text/plain; charset=UTF-8
Content-Transfer-Encoding: 8bit

Ordering + limit-only Test für created_at DESC in DependencyExtractionFeatureTest.php
UI Test für masked Identifier (ID: 123456…) + Guest-Access blocked in InventoryItemDependenciesTest.php
Quickstart ergänzt um manuellen <2s Check in quickstart.md
pr-gate Checkbox-Format normalisiert (kein leading space) in pr-gate.md

Co-authored-by: Ahmed Darrazi <ahmeddarrazi@adsmac.local>
Reviewed-on: https://git.cloudarix.de/ahmido/TenantAtlas/pulls/49
---
 .github/agents/copilot-instructions.md        |   4 +-
 .../Resources/InventoryItemResource.php       |  32 ++
 app/Models/InventoryLink.php                  |  22 ++
 .../Inventory/DependencyExtractionService.php | 147 ++++++++++
 .../Inventory/DependencyQueryService.php      |  40 +++
 .../Inventory/InventorySyncService.php        |  22 +-
 app/Support/Enums/RelationshipType.php        |  35 +++
 database/factories/InventoryLinkFactory.php   |  30 ++
 ...07_150000_create_inventory_links_table.php |  40 +++
 .../components/dependency-edges.blade.php     |  66 +++++
 .../checklists/dependencies.md                |  78 +++++
 .../checklists/pr-gate.md                     |  76 +++++
 .../checklists/requirements.md                |  37 +++
 .../contracts/README.md                       |   5 +
 .../contracts/dependency-edge.schema.json     |  33 +++
 .../data-model.md                             |  72 +++++
 .../042-inventory-dependencies-graph/plan.md  | 104 ++++++-
 .../quickstart.md                             |  34 +++
 .../research.md                               |  47 +++
 .../042-inventory-dependencies-graph/spec.md  | 146 +++++++++-
 .../042-inventory-dependencies-graph/tasks.md | 203 ++++++++++++-
 .../DependencyExtractionFeatureTest.php       | 275 ++++++++++++++++++
 tests/Feature/DependencyQueryServiceTest.php  |  45 +++
 .../Feature/DependencyTenantIsolationTest.php |  43 +++
 .../Feature/InventoryItemDependenciesTest.php | 188 ++++++++++++
 .../Unit/DependencyExtractionServiceTest.php  |  82 ++++++
 tests/Unit/InventoryLinkTest.php              |  52 ++++
 27 files changed, 1921 insertions(+), 37 deletions(-)
 create mode 100644 app/Models/InventoryLink.php
 create mode 100644 app/Services/Inventory/DependencyExtractionService.php
 create mode 100644 app/Services/Inventory/DependencyQueryService.php
 create mode 100644 app/Support/Enums/RelationshipType.php
 create mode 100644 database/factories/InventoryLinkFactory.php
 create mode 100644 database/migrations/2026_01_07_150000_create_inventory_links_table.php
 create mode 100644 resources/views/filament/components/dependency-edges.blade.php
 create mode 100644 specs/042-inventory-dependencies-graph/checklists/dependencies.md
 create mode 100644 specs/042-inventory-dependencies-graph/checklists/pr-gate.md
 create mode 100644 specs/042-inventory-dependencies-graph/checklists/requirements.md
 create mode 100644 specs/042-inventory-dependencies-graph/contracts/README.md
 create mode 100644 specs/042-inventory-dependencies-graph/contracts/dependency-edge.schema.json
 create mode 100644 specs/042-inventory-dependencies-graph/data-model.md
 create mode 100644 specs/042-inventory-dependencies-graph/quickstart.md
 create mode 100644 specs/042-inventory-dependencies-graph/research.md
 create mode 100644 tests/Feature/DependencyExtractionFeatureTest.php
 create mode 100644 tests/Feature/DependencyQueryServiceTest.php
 create mode 100644 tests/Feature/DependencyTenantIsolationTest.php
 create mode 100644 tests/Feature/InventoryItemDependenciesTest.php
 create mode 100644 tests/Unit/DependencyExtractionServiceTest.php
 create mode 100644 tests/Unit/InventoryLinkTest.php

diff --git a/.github/agents/copilot-instructions.md b/.github/agents/copilot-instructions.md
index 0fb9ff8..c0e52ea 100644
--- a/.github/agents/copilot-instructions.md
+++ b/.github/agents/copilot-instructions.md
@@ -6,6 +6,8 @@ ## Active Technologies
 - PHP 8.4.15 + Laravel 12, Filament v4, Livewire v3 (feat/005-bulk-operations)
 - PostgreSQL (app), SQLite in-memory (tests) (feat/005-bulk-operations)
 - PostgreSQL (Sail locally) (feat/032-backup-scheduling-mvp)
+- PHP 8.4.x + Laravel 12, Filament v4, Livewire v3 (feat/042-inventory-dependencies-graph)
+- PostgreSQL (JSONB) (feat/042-inventory-dependencies-graph)
 
 - PHP 8.4.15 (feat/005-bulk-operations)
 
@@ -25,10 +27,10 @@ ## Code Style
 PHP 8.4.15: Follow standard conventions
 
 ## Recent Changes
+- feat/042-inventory-dependencies-graph: Added PHP 8.4.x + Laravel 12, Filament v4, Livewire v3
 - feat/032-backup-scheduling-mvp: Added PHP 8.4.15 + Laravel 12, Filament v4, Livewire v3
 - feat/005-bulk-operations: Added PHP 8.4.15 + Laravel 12, Filament v4, Livewire v3
 
-- feat/005-bulk-operations: Added PHP 8.4.15
 
 <!-- MANUAL ADDITIONS START -->
 <!-- MANUAL ADDITIONS END -->
diff --git a/app/Filament/Resources/InventoryItemResource.php b/app/Filament/Resources/InventoryItemResource.php
index 96e6856..90ccf71 100644
--- a/app/Filament/Resources/InventoryItemResource.php
+++ b/app/Filament/Resources/InventoryItemResource.php
@@ -5,6 +5,8 @@
 use App\Filament\Resources\InventoryItemResource\Pages;
 use App\Models\InventoryItem;
 use App\Models\Tenant;
+use App\Services\Inventory\DependencyQueryService;
+use App\Support\Enums\RelationshipType;
 use BackedEnum;
 use Filament\Actions;
 use Filament\Infolists\Components\TextEntry;
@@ -70,6 +72,36 @@ public static function infolist(Schema $schema): Schema
                     ->columns(2)
                     ->columnSpanFull(),
 
+                Section::make('Dependencies')
+                    ->schema([
+                        ViewEntry::make('dependencies')
+                            ->label('')
+                            ->view('filament.components.dependency-edges')
+                            ->state(function (InventoryItem $record) {
+                                $direction = request()->query('direction', 'all');
+                                $relationshipType = request()->query('relationship_type', 'all');
+                                $relationshipType = is_string($relationshipType) ? $relationshipType : 'all';
+
+                                $relationshipType = $relationshipType === 'all'
+                                    ? null
+                                    : RelationshipType::tryFrom($relationshipType)?->value;
+
+                                $service = app(DependencyQueryService::class);
+
+                                $edges = collect();
+                                if ($direction === 'inbound' || $direction === 'all') {
+                                    $edges = $edges->merge($service->getInboundEdges($record, $relationshipType));
+                                }
+                                if ($direction === 'outbound' || $direction === 'all') {
+                                    $edges = $edges->merge($service->getOutboundEdges($record, $relationshipType));
+                                }
+
+                                return $edges->take(100); // both directions combined
+                            })
+                            ->columnSpanFull(),
+                    ])
+                    ->columnSpanFull(),
+
                 Section::make('Metadata (Safe Subset)')
                     ->schema([
                         ViewEntry::make('meta_jsonb')
diff --git a/app/Models/InventoryLink.php b/app/Models/InventoryLink.php
new file mode 100644
index 0000000..ee061d4
--- /dev/null
+++ b/app/Models/InventoryLink.php
@@ -0,0 +1,22 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+
+class InventoryLink extends Model
+{
+    use HasFactory;
+
+    protected $table = 'inventory_links';
+
+    protected $guarded = [];
+
+    protected function casts(): array
+    {
+        return [
+            'metadata' => 'array',
+        ];
+    }
+}
diff --git a/app/Services/Inventory/DependencyExtractionService.php b/app/Services/Inventory/DependencyExtractionService.php
new file mode 100644
index 0000000..54ad580
--- /dev/null
+++ b/app/Services/Inventory/DependencyExtractionService.php
@@ -0,0 +1,147 @@
+<?php
+
+namespace App\Services\Inventory;
+
+use App\Models\InventoryItem;
+use App\Models\InventoryLink;
+use App\Support\Enums\RelationshipType;
+use Illuminate\Support\Arr;
+use Illuminate\Support\Collection;
+use Illuminate\Support\Facades\Log;
+
+class DependencyExtractionService
+{
+    /**
+     * Extracts dependencies for a given inventory item using the raw policy payload if available.
+     * Idempotent via unique key on inventory_links. Enforces a max of 50 outbound edges per item.
+     *
+     * @param  array<string, mixed>  $policyData
+     */
+    public function extractForPolicyData(InventoryItem $item, array $policyData): array
+    {
+        $warnings = [];
+        $edges = collect();
+
+        $edges = $edges->merge($this->extractAssignedTo($item, $policyData, $warnings));
+        $edges = $edges->merge($this->extractScopedBy($item, $policyData));
+
+        // Enforce max 50 outbound edges by priority: assigned_to > scoped_by > others
+        $priorities = [
+            RelationshipType::AssignedTo->value => 1,
+            RelationshipType::ScopedBy->value => 2,
+            RelationshipType::Targets->value => 3,
+            RelationshipType::DependsOn->value => 4,
+        ];
+
+        /** @var Collection<int, array{tenant_id:int,source_type:string,source_id:string,target_type:string,target_id:?string,relationship_type:string,metadata:array}> $sorted */
+        $sorted = $edges->sortBy(fn ($e) => $priorities[$e['relationship_type']] ?? 99)->values();
+
+        $limited = $sorted->take(50);
+
+        $now = now();
+        $payload = $limited->map(function (array $e) use ($now) {
+            $metadata = $e['metadata'] ?? null;
+            if (is_array($metadata)) {
+                // Ensure portability across SQLite/Postgres when using upsert via query builder
+                $e['metadata'] = json_encode($metadata);
+            }
+
+            return array_merge($e, [
+                'created_at' => $now,
+                'updated_at' => $now,
+            ]);
+        })->all();
+
+        if (! empty($payload)) {
+            InventoryLink::query()->upsert(
+                $payload,
+                ['tenant_id', 'source_type', 'source_id', 'target_type', 'target_id', 'relationship_type'],
+                ['metadata', 'updated_at']
+            );
+        }
+
+        return $warnings;
+    }
+
+    /**
+     * @param  array<string, mixed>  $policyData
+     * @return Collection<int, array<string, mixed>>
+     */
+    private function extractAssignedTo(InventoryItem $item, array $policyData, array &$warnings): Collection
+    {
+        $assignments = Arr::get($policyData, 'assignments');
+        if (! is_array($assignments)) {
+            return collect();
+        }
+
+        $edges = [];
+
+        foreach ($assignments as $assignment) {
+            if (! is_array($assignment)) {
+                continue;
+            }
+
+            // Known shapes: ['target' => ['groupId' => '...']] or direct ['groupId' => '...']
+            $groupId = Arr::get($assignment, 'target.groupId') ?? Arr::get($assignment, 'groupId');
+            if (is_string($groupId) && $groupId !== '') {
+                $edges[] = [
+                    'tenant_id' => (int) $item->tenant_id,
+                    'source_type' => 'inventory_item',
+                    'source_id' => (string) $item->external_id,
+                    'target_type' => 'foundation_object',
+                    'target_id' => $groupId,
+                    'relationship_type' => RelationshipType::AssignedTo->value,
+                    'metadata' => [
+                        'last_known_name' => null,
+                        'foundation_type' => 'aad_group',
+                    ],
+                ];
+            } else {
+                $warning = [
+                    'type' => 'unsupported_reference',
+                    'policy_id' => (string) ($policyData['id'] ?? $item->external_id),
+                    'raw_ref' => $assignment,
+                    'reason' => 'unsupported_assignment_target_shape',
+                ];
+
+                $warnings[] = $warning;
+                Log::info('Unsupported reference shape encountered', $warning);
+            }
+        }
+
+        return collect($edges);
+    }
+
+    /**
+     * @param  array<string, mixed>  $policyData
+     * @return Collection<int, array<string, mixed>>
+     */
+    private function extractScopedBy(InventoryItem $item, array $policyData): Collection
+    {
+        $scopeTags = Arr::get($policyData, 'roleScopeTagIds');
+        if (! is_array($scopeTags)) {
+            return collect();
+        }
+
+        $edges = [];
+
+        foreach ($scopeTags as $tagId) {
+            if (is_string($tagId) && $tagId !== '') {
+                $edges[] = [
+                    'tenant_id' => (int) $item->tenant_id,
+                    'source_type' => 'inventory_item',
+                    'source_id' => (string) $item->external_id,
+                    'target_type' => 'foundation_object',
+                    'target_id' => $tagId,
+                    'relationship_type' => RelationshipType::ScopedBy->value,
+                    'metadata' => [
+                        'last_known_name' => null,
+                        'foundation_type' => 'scope_tag',
+                    ],
+                ];
+            }
+        }
+
+        return collect($edges);
+    }
+}
diff --git a/app/Services/Inventory/DependencyQueryService.php b/app/Services/Inventory/DependencyQueryService.php
new file mode 100644
index 0000000..089d047
--- /dev/null
+++ b/app/Services/Inventory/DependencyQueryService.php
@@ -0,0 +1,40 @@
+<?php
+
+namespace App\Services\Inventory;
+
+use App\Models\InventoryItem;
+use App\Models\InventoryLink;
+use Illuminate\Database\Eloquent\Collection as EloquentCollection;
+
+class DependencyQueryService
+{
+    public function getOutboundEdges(InventoryItem $item, ?string $relationshipType = null, int $limit = 50): EloquentCollection
+    {
+        $query = InventoryLink::query()
+            ->where('tenant_id', $item->tenant_id)
+            ->where('source_type', 'inventory_item')
+            ->where('source_id', $item->external_id)
+            ->orderByDesc('created_at');
+
+        if ($relationshipType !== null) {
+            $query->where('relationship_type', $relationshipType);
+        }
+
+        return $query->limit($limit)->get();
+    }
+
+    public function getInboundEdges(InventoryItem $item, ?string $relationshipType = null, int $limit = 50): EloquentCollection
+    {
+        $query = InventoryLink::query()
+            ->where('tenant_id', $item->tenant_id)
+            ->where('target_type', 'inventory_item')
+            ->where('target_id', $item->external_id)
+            ->orderByDesc('created_at');
+
+        if ($relationshipType !== null) {
+            $query->where('relationship_type', $relationshipType);
+        }
+
+        return $query->limit($limit)->get();
+    }
+}
diff --git a/app/Services/Inventory/InventorySyncService.php b/app/Services/Inventory/InventorySyncService.php
index a43e693..e581016 100644
--- a/app/Services/Inventory/InventorySyncService.php
+++ b/app/Services/Inventory/InventorySyncService.php
@@ -239,6 +239,7 @@ private function executeRun(InventorySyncRun $run, Tenant $tenant, array $normal
         $errors = 0;
         $errorCodes = [];
         $hadErrors = false;
+        $warnings = [];
 
         try {
             $typesConfig = $this->supportedTypeConfigByType();
@@ -307,7 +308,7 @@ private function executeRun(InventorySyncRun $run, Tenant $tenant, array $normal
                         'warnings' => [],
                     ]);
 
-                    InventoryItem::query()->updateOrCreate(
+                    $item = InventoryItem::query()->updateOrCreate(
                         [
                             'tenant_id' => $tenant->getKey(),
                             'policy_type' => $policyType,
@@ -324,6 +325,16 @@ private function executeRun(InventorySyncRun $run, Tenant $tenant, array $normal
                     );
 
                     $upserted++;
+
+                    // Extract dependencies if requested in selection
+                    $includeDeps = (bool) ($normalizedSelection['include_dependencies'] ?? true);
+                    if ($includeDeps) {
+                        $warnings = array_merge(
+                            $warnings,
+                            app(\App\Services\Inventory\DependencyExtractionService::class)
+                                ->extractForPolicyData($item, $policyData)
+                        );
+                    }
                 }
 
                 $onPolicyTypeProcessed && $onPolicyTypeProcessed($policyType, true, null);
@@ -335,7 +346,9 @@ private function executeRun(InventorySyncRun $run, Tenant $tenant, array $normal
                 'status' => $status,
                 'had_errors' => $hadErrors,
                 'error_codes' => array_values(array_unique($errorCodes)),
-                'error_context' => null,
+                'error_context' => [
+                    'warnings' => array_values($warnings),
+                ],
                 'items_observed_count' => $observed,
                 'items_upserted_count' => $upserted,
                 'errors_count' => $errors,
@@ -344,11 +357,14 @@ private function executeRun(InventorySyncRun $run, Tenant $tenant, array $normal
 
             return $run->refresh();
         } catch (Throwable $throwable) {
+            $errorContext = $this->safeErrorContext($throwable);
+            $errorContext['warnings'] = array_values($warnings);
+
             $run->update([
                 'status' => InventorySyncRun::STATUS_FAILED,
                 'had_errors' => true,
                 'error_codes' => ['unexpected_exception'],
-                'error_context' => $this->safeErrorContext($throwable),
+                'error_context' => $errorContext,
                 'items_observed_count' => $observed,
                 'items_upserted_count' => $upserted,
                 'errors_count' => $errors + 1,
diff --git a/app/Support/Enums/RelationshipType.php b/app/Support/Enums/RelationshipType.php
new file mode 100644
index 0000000..2c1f101
--- /dev/null
+++ b/app/Support/Enums/RelationshipType.php
@@ -0,0 +1,35 @@
+<?php
+
+namespace App\Support\Enums;
+
+enum RelationshipType: string
+{
+    case AssignedTo = 'assigned_to';
+    case ScopedBy = 'scoped_by';
+    case Targets = 'targets';
+    case DependsOn = 'depends_on';
+
+    public function label(): string
+    {
+        return match ($this) {
+            self::AssignedTo => 'Assigned to',
+            self::ScopedBy => 'Scoped by',
+            self::Targets => 'Targets',
+            self::DependsOn => 'Depends on',
+        };
+    }
+
+    /**
+     * @return array<string, string>
+     */
+    public static function options(): array
+    {
+        $options = [];
+
+        foreach (self::cases() as $case) {
+            $options[$case->value] = $case->label();
+        }
+
+        return $options;
+    }
+}
diff --git a/database/factories/InventoryLinkFactory.php b/database/factories/InventoryLinkFactory.php
new file mode 100644
index 0000000..e508e37
--- /dev/null
+++ b/database/factories/InventoryLinkFactory.php
@@ -0,0 +1,30 @@
+<?php
+
+namespace Database\Factories;
+
+use App\Models\InventoryLink;
+use App\Models\Tenant;
+use Illuminate\Database\Eloquent\Factories\Factory;
+
+/**
+ * @extends Factory<InventoryLink>
+ */
+class InventoryLinkFactory extends Factory
+{
+    protected $model = InventoryLink::class;
+
+    public function definition(): array
+    {
+        return [
+            'tenant_id' => Tenant::factory(),
+            'source_type' => 'inventory_item',
+            'source_id' => $this->faker->uuid(),
+            'target_type' => 'foundation_object',
+            'target_id' => $this->faker->uuid(),
+            'relationship_type' => 'assigned_to',
+            'metadata' => [
+                'last_known_name' => $this->faker->words(3, true),
+            ],
+        ];
+    }
+}
diff --git a/database/migrations/2026_01_07_150000_create_inventory_links_table.php b/database/migrations/2026_01_07_150000_create_inventory_links_table.php
new file mode 100644
index 0000000..ea1a6d7
--- /dev/null
+++ b/database/migrations/2026_01_07_150000_create_inventory_links_table.php
@@ -0,0 +1,40 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('inventory_links', function (Blueprint $table) {
+            $table->id();
+            $table->foreignId('tenant_id')->constrained()->cascadeOnDelete();
+            $table->string('source_type');
+            $table->uuid('source_id');
+            $table->string('target_type');
+            $table->uuid('target_id')->nullable();
+            $table->string('relationship_type');
+            $table->jsonb('metadata')->nullable();
+            $table->timestamps();
+
+            $table->unique([
+                'tenant_id',
+                'source_type',
+                'source_id',
+                'target_type',
+                'target_id',
+                'relationship_type',
+            ], 'inventory_links_unique');
+
+            $table->index(['tenant_id', 'source_type', 'source_id']);
+            $table->index(['tenant_id', 'target_type', 'target_id']);
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('inventory_links');
+    }
+};
diff --git a/resources/views/filament/components/dependency-edges.blade.php b/resources/views/filament/components/dependency-edges.blade.php
new file mode 100644
index 0000000..fcaec87
--- /dev/null
+++ b/resources/views/filament/components/dependency-edges.blade.php
@@ -0,0 +1,66 @@
+@php /** @var callable $getState */ @endphp
+
+<div class="space-y-4">
+    <form method="GET" class="flex items-center gap-2">
+        <label for="direction" class="text-sm text-gray-600">Direction</label>
+        <select id="direction" name="direction" class="fi-input fi-select">
+            <option value="all" {{ request('direction', 'all') === 'all' ? 'selected' : '' }}>All</option>
+            <option value="inbound" {{ request('direction') === 'inbound' ? 'selected' : '' }}>Inbound</option>
+            <option value="outbound" {{ request('direction') === 'outbound' ? 'selected' : '' }}>Outbound</option>
+        </select>
+
+        <label for="relationship_type" class="text-sm text-gray-600">Relationship</label>
+        <select id="relationship_type" name="relationship_type" class="fi-input fi-select">
+            <option value="all" {{ request('relationship_type', 'all') === 'all' ? 'selected' : '' }}>All</option>
+            @foreach (\App\Support\Enums\RelationshipType::options() as $value => $label)
+                <option value="{{ $value }}" {{ request('relationship_type') === $value ? 'selected' : '' }}>{{ $label }}</option>
+            @endforeach
+        </select>
+        <button type="submit" class="fi-btn">Apply</button>
+    </form>
+
+    @php
+        $raw = $getState();
+        $edges = $raw instanceof \Illuminate\Support\Collection ? $raw : collect($raw);
+    @endphp
+
+    @if ($edges->isEmpty())
+        <div class="text-sm text-gray-500">No dependencies found</div>
+    @else
+        <div class="divide-y">
+            @foreach ($edges->groupBy('relationship_type') as $type => $group)
+                <div class="py-2">
+                    <div class="text-xs uppercase tracking-wide text-gray-600 mb-2">{{ str_replace('_', ' ', $type) }}</div>
+                    <ul class="space-y-1">
+                        @foreach ($group as $edge)
+                            @php
+                                $isMissing = ($edge['target_type'] ?? null) === 'missing';
+                                $name = $edge['metadata']['last_known_name'] ?? null;
+                                $targetId = $edge['target_id'] ?? null;
+                                $display = $name ?: ($targetId ? ("ID: ".substr($targetId,0,6)."…") : 'Unknown');
+
+                                $missingTitle = 'Missing target';
+                                if (is_string($name) && $name !== '') {
+                                    $missingTitle .= ". Last known: {$name}";
+                                }
+                                $rawRef = $edge['metadata']['raw_ref'] ?? null;
+                                if ($rawRef !== null) {
+                                    $encodedRef = json_encode($rawRef);
+                                    if (is_string($encodedRef) && $encodedRef !== '') {
+                                        $missingTitle .= '. Ref: '.\Illuminate\Support\Str::limit($encodedRef, 200);
+                                    }
+                                }
+                            @endphp
+                            <li class="flex items-center gap-2 text-sm">
+                                <span class="fi-badge" title="{{ is_string($targetId) ? $targetId : '' }}">{{ $display }}</span>
+                                @if ($isMissing)
+                                    <span class="fi-badge fi-badge-danger" title="{{ $missingTitle }}">Missing</span>
+                                @endif
+                            </li>
+                        @endforeach
+                    </ul>
+                </div>
+            @endforeach
+        </div>
+    @endif
+</div>
diff --git a/specs/042-inventory-dependencies-graph/checklists/dependencies.md b/specs/042-inventory-dependencies-graph/checklists/dependencies.md
new file mode 100644
index 0000000..62ed54a
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/checklists/dependencies.md
@@ -0,0 +1,78 @@
+# Dependencies Checklist: Inventory Dependencies Graph
+
+**Purpose**: Validate that Spec 042’s dependency-graph requirements are complete, unambiguous, and testable ("unit tests for English").
+**Created**: 2026-01-07
+**Feature**: `specs/042-inventory-dependencies-graph/spec.md`
+
+**Note**: This checklist is generated by the `/speckit.checklist` command based on feature context and requirements.
+
+## Requirement Completeness
+
+- [x] CHK001 Are relationship types fully enumerated with definitions and at least one example per type? [Completeness, Spec §FR1]
+- [x] CHK002 Are the minimum required fields for a dependency edge explicitly specified (e.g., source, target, type, directionality, timestamps, provenance)? [Gap, Spec §FR2]
+- [x] CHK003 Are the categories of “other objects” (non-inventory foundations) explicitly enumerated and bounded (what is in-scope vs out-of-scope)? [Completeness, Spec §FR2]
+- [x] CHK004 Are the identifiers/keys used to reference inventory items and foundational objects clearly specified (stable IDs vs display names)? [Gap, Plan §Dependencies]
+- [x] CHK005 Are inbound and outbound edge queries both explicitly required for all supported relationship types (or are exceptions called out)? [Completeness, Spec §FR3]
+- [x] CHK006 Are “missing prerequisites” criteria specified (what counts as missing, and how missing is detected)? [Completeness, Spec §Scenario 2, FR4]
+- [x] CHK007 Are access control requirements defined beyond “access-controlled” (roles/permissions, tenant admin vs read-only, etc.)? [Gap, Spec §FR5]
+
+## Requirement Clarity
+
+- [x] CHK008 Is the meaning of “inbound” vs “outbound” relationships defined unambiguously (especially for asymmetric relations like “assigned to”)? [Clarity, Spec §Scenario 1, FR3]
+- [x] CHK009 Are relationship labels (“uses”, “assigned to”, “scoped by”) defined as a taxonomy with consistent naming, directionality, and semantics? [Clarity, Spec §Scenario 1, FR1]
+- [x] CHK010 Is “blast radius” translated into concrete, observable dependency-graph concepts (e.g., outbound edges only, both directions, depth)? [Ambiguity, Spec §Purpose]
+- [x] CHK011 Is “prerequisite” defined precisely (e.g., hard prerequisite vs informational dependency; required vs optional)? [Ambiguity, Spec §Purpose, Scenario 2]
+- [x] CHK012 Is the filter behavior for relationship types specified (single vs multi-select, default selection, empty selection meaning)? [Gap, Spec §Scenario 3]
+- [x] CHK013 Are “safe warning” requirements specified with a format/fields and where they surface (sync logs, UI banner, audit log)? [Clarity, Spec §NFR2]
+
+## Requirement Consistency
+
+- [x] CHK014 Do “missing prerequisites” requirements align with “no separate deleted state in core inventory” without introducing contradictory states or terminology? [Consistency, Spec §FR4]
+- [x] CHK015 Are the relationship examples in scenarios consistent with the relationship taxonomy required by FR1 (no scenario-only types)? [Consistency, Spec §Scenario 1, FR1]
+- [x] CHK016 Do idempotency requirements (NFR1) align with determinism requirements (SC2) without ambiguity about ordering, deduplication, or normalization? [Consistency, Spec §NFR1, SC2]
+- [x] CHK017 Are tenant-scoping requirements consistent across storage, querying, and UI exposure (no implied cross-tenant joins)? [Consistency, Spec §FR5, Out of Scope]
+
+## Acceptance Criteria Quality
+
+- [x] CHK018 Is SC1 (“under 2 minutes”) made measurable with a defined starting point, scope (single item, depth), and success signal (what the admin must be able to conclude)? [Measurability, Spec §SC1]
+- [x] CHK019 Is SC2 (“deterministic output”) made measurable by defining what equivalence means (edge set equality, stable IDs, normalized relationship types)? [Measurability, Spec §SC2]
+ - [x] CHK020 Are acceptance criteria mapped to each Functional Requirement (FR1–FR5) so each requirement has an objective pass/fail definition? [Gap, Spec §Functional Requirements]
+
+## Scenario Coverage
+
+- [x] CHK021 Do scenarios cover both inbound and outbound viewing requirements explicitly (or is one direction implicitly assumed)? [Coverage, Spec §Scenario 1, FR3]
+- [x] CHK022 Are scenarios defined for “no dependencies” (zero edges) and how that is communicated to the user? [Gap, Spec §User Scenarios & Testing]
+ - [x] CHK023 Are scenarios defined for “only missing prerequisites” (all targets missing) and how that impacts filtering or display? [Gap, Spec §Scenario 2]
+- [x] CHK024 Are scenarios defined for mixed object types (inventory item → foundation object, foundation → inventory item) if both are supported? [Gap, Spec §FR2]
+
+## Edge Case Coverage
+
+- [x] CHK025 Are requirements specified for unknown/unsupported references beyond “record a safe warning” (e.g., whether an edge is skipped, recorded as unknown node, or preserved as raw ref)? [Coverage, Spec §NFR2]
+- [x] CHK026 Are requirements defined for duplicate references within a single item (e.g., same target referenced multiple times) and expected edge deduplication rules? [Gap, Spec §NFR1, SC2]
+ - [x] CHK027 Are cyclic dependencies explicitly addressed (allow, detect, show, and/or bound traversal depth)? [Gap, Spec §Purpose]
+- [x] CHK028 Are requirements defined for very large graphs (pagination, depth limits, maximum edges returned) given the stated “edge explosion” risk? [Gap, Plan §Risks]
+
+## Non-Functional Requirements
+
+- [x] CHK029 Does NFR1 define idempotency scope and mechanism expectations (e.g., uniqueness keys, replace-all vs upsert, run-scoped vs global)? [Clarity, Spec §NFR1]
+- [x] CHK030 Does NFR2 define what constitutes “must not fail an inventory sync run” (soft-fail boundary, error severity classes, retries)? [Clarity, Spec §NFR2]
+- [x] CHK031 Are performance requirements (latency, memory, query limits) specified for dependency extraction and for dependency viewing queries? [Gap, Plan §Risks]
+ - [x] CHK032 Are security/privacy requirements specified for what dependency data may expose (e.g., names/IDs of foundation objects) and who can see it? [Gap, Spec §FR5]
+
+## Dependencies & Assumptions
+
+- [x] CHK033 Are dependencies on Spec 040 identifiers and Spec 041 UI explicitly stated as hard requirements vs optional integration points? [Clarity, Plan §Dependencies]
+- [x] CHK034 Are assumptions documented about which Intune object types contain references and the reference shapes expected (“heterogeneous reference shapes” risk)? [Assumption, Plan §Risks]
+- [x] CHK035 Are assumptions documented about data freshness (when edges are extracted relative to inventory sync, and how stale edges are handled)? [Gap, Spec §NFR1]
+
+## Ambiguities & Conflicts
+
+- [x] CHK036 Is “foundation object not present in inventory” terminology consistent with “not requiring a deleted state” (missing vs absent vs excluded)? [Ambiguity, Spec §FR4]
+- [x] CHK037 Is it explicitly defined whether cross-item dependencies are limited to within a policy type or across all inventory types? [Gap, Spec §Purpose, FR2]
+- [x] CHK038 Is it clear whether relationship filtering applies only to edge types, or also to node/object types (inventory vs foundations)? [Gap, Spec §Scenario 3]
+
+## Notes
+
+- Check items off as completed: `[x]`
+- Add findings inline under the relevant checklist item
+- Each `/speckit.checklist` run creates a new checklist file
diff --git a/specs/042-inventory-dependencies-graph/checklists/pr-gate.md b/specs/042-inventory-dependencies-graph/checklists/pr-gate.md
new file mode 100644
index 0000000..d865ef7
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/checklists/pr-gate.md
@@ -0,0 +1,76 @@
+# PR Gate Checklist: Inventory Dependencies Graph
+
+**Purpose**: PR-Review-Checklist zur Bewertung der Anforderungsqualität für Spec 042 (50% Daten/Pipeline, 50% Darstellung). Fokus: messbar, deterministisch reviewbar, scope-stabil durch „Enumerate now“.
+**Created**: 2026-01-07
+**Feature**: `specs/042-inventory-dependencies-graph/spec.md`
+
+**Note**: This checklist is generated by the `/speckit.checklist` command based on feature context and requirements.
+
+## Requirement Completeness
+
+- [x] CHK001 Ist die Relationship-Taxonomie vollständig enumeriert (Set an Typen) und pro Typ mit Definition + Richtung + Beispiel beschrieben? [Completeness, Spec §FR1]
+- [x] CHK002 Sind alle in-scope „foundational Intune objects“ explizit aufgelistet (Enumerate now) inkl. klarer Exclusions, um Scope zu binden? [Gap, Spec §FR2, Plan §Risks]
+- [x] CHK003 Sind Mindestfelder einer Dependency-Edge als Requirement beschrieben (source, target, relationship_type, directionality, provenance/derived_from, timestamps/created_at, optional metadata)? [Gap, Spec §FR2]
+- [x] CHK004 Ist klar spezifiziert, wie „inventory item“ eindeutig referenziert wird (stable identifier), und wie foundation objects referenziert werden (ID/uri/type tuple)? [Gap, Plan §Dependencies]
+- [x] CHK005 Sind inbound UND outbound Abfragen als explizite Requirements beschrieben (inkl. erwarteter Sortierung/Limitierung oder bewusst „unspecified“)? [Completeness, Spec §FR3]
+- [x] CHK006 Sind Missing-Prerequisites als eigene Requirement-Klasse beschrieben (Erkennung, Darstellung, und welche Daten minimal gezeigt werden dürfen)? [Completeness, Spec §FR4, Scenario 2]
+- [x] CHK007 Ist Relationship-Type-Filtering vollständig spezifiziert (Scope, Default, Mehrfachauswahl ja/nein, Verhalten bei „none selected“)? [Completeness, Spec §Scenario 3]
+- [x] CHK008 Sind Tenant-Scoping und Access Control Requirements konkretisiert (welche Rollen/Capabilities; Read vs View Details; ggf. audit expectations)? [Gap, Spec §FR5]
+
+## Requirement Clarity
+
+- [x] CHK009 Ist „inbound“ vs „outbound“ formal definiert pro Relationship-Type (nicht nur im Textbeispiel), um Interpretationsspielraum zu vermeiden? [Clarity, Spec §Scenario 1, FR3]
+- [x] CHK010 Sind Relationship-Namen und Semantik konsistent (z.B. „assigned to“ ist eindeutig Richtung A→B) und nicht synonym/überlappend? [Clarity, Spec §FR1]
+- [x] CHK011 Ist „blast radius“ in messbare Graph-Konzepte übersetzt (z.B. „outbound edges bis Tiefe N“, „both directions“, oder explizit „only direct neighbors“)? [Ambiguity, Spec §Purpose]
+- [x] CHK012 Ist „prerequisite“ eindeutig definiert (hard vs informational, required vs optional) und ist diese Definition in Missing-Prerequisites konsistent wiederverwendet? [Ambiguity, Spec §Purpose, Scenario 2]
+- [x] CHK013 Ist „safe warning“ (NFR2) klar operationalisiert: Inhalt/Felder, Severity, Persistenz, und wo es sichtbar wird (Run-Log vs UI vs Audit)? [Clarity, Spec §NFR2]
+
+## Requirement Consistency
+
+- [x] CHK014 Sind Scenario-Beispiele („uses“, „assigned to“, „scoped by“) vollständig Teil der FR1-Taxonomie (keine scenario-only Typen)? [Consistency, Spec §Scenario 1, FR1]
+- [x] CHK015 Ist FR4 („missing prerequisites“) konsistent mit „ohne deleted state in core inventory“ beschrieben (kein implizites soft-delete/archived eingeführt)? [Consistency, Spec §FR4]
+- [x] CHK016 Sind NFR1 (idempotent) und SC2 (deterministic output) konfliktfrei und eindeutig, was Gleichheit bedeutet (Edge-Set, Normalisierung, Sortierung)? [Consistency, Spec §NFR1, SC2]
+- [x] CHK017 Ist der Tenant-Scope konsistent in Storage, Query und UI (keine impliziten cross-tenant Graphs; Out-of-scope ist explizit)? [Consistency, Spec §FR5, Out of Scope]
+
+## Acceptance Criteria Quality
+
+- [x] CHK018 Ist SC1 („unter 2 Minuten“) so definiert, dass Reviewer objektiv prüfen können, was „determine prerequisites and blast radius“ konkret bedeutet (Tiefe, Umfang, Informationsumfang)? [Measurability, Spec §SC1]
+- [x] CHK019 Ist SC2 so messbar formuliert, dass deterministische Output-Gleichheit ohne Interpretationsspielraum prüfbar ist (z.B. canonical ordering + uniqueness rules)? [Measurability, Spec §SC2]
+- [x] CHK020 Gibt es eine klare Traceability zwischen FR1–FR5 und Success Criteria (jedes FR hat mindestens ein objektives Akzeptanzkriterium oder ist bewusst als „non-testable“ markiert)? [Gap, Spec §Functional Requirements, Success Criteria]
+
+## Scenario Coverage
+
+- [x] CHK021 Deckt die Spec explizit den Zero-State ab („no edges“ / „no deps“), inkl. erwarteter UI-Messaging-Requirement? [Gap, Spec §User Scenarios & Testing]
+- [x] CHK022 Deckt die Spec explizit Mixed-Targets ab (Inventory→Foundation, Inventory→Inventory) und ob Foundation→Inventory als inbound dargestellt werden soll? [Gap, Spec §FR2, FR3]
+- [x] CHK023 Gibt es definierte Requirements für „only missing prerequisites“ (alle Targets missing) und wie Filter/Display damit umgehen? [Gap, Spec §Scenario 2]
+
+## Edge Case Coverage
+
+- [x] CHK024 Sind Unknown/Unsupported References (NFR2) vollständig als Requirements abgedeckt: ob Edge erzeugt wird, ob Node „unknown“ erlaubt ist, ob raw reference gespeichert wird? [Coverage, Spec §NFR2]
+- [x] CHK025 Sind Duplicate References innerhalb eines Items geregelt (Dedup-Key, Merge Rules), um NFR1/SC2 deterministisch einzuhalten? [Gap, Spec §NFR1, SC2]
+- [x] CHK026 Sind zyklische Dependencies als Requirement adressiert (Erkennung/Handling/Traversal-Limits), damit „blast radius“ nicht unendlich wird? [Gap, Spec §Purpose, Plan §Risks]
+- [x] CHK027 Sind Grenzen für Edge-Explosion als Requirements spezifiziert (Limits, pagination, depth caps, server-side constraints), nicht nur als Risiko erwähnt? [Gap, Plan §Risks]
+
+## Non-Functional Requirements
+
+- [x] CHK028 Ist Idempotenz (NFR1) präzisiert: Scope (per-run vs global), Unique Keys, Upsert vs Replace-All, und ob Deletions/Orphan-Edges geregelt sind? [Clarity, Spec §NFR1]
+- [x] CHK029 Ist „must not fail an inventory sync run“ präzisiert: welche Fehler sind soft-fail, welche sind hard-fail, und wie wird das für Reviewer nachvollziehbar? [Clarity, Spec §NFR2]
+- [x] CHK030 Sind Performance-/Skalierungsanforderungen spezifiziert (UI Query Latency, max edges returned, extraction time budget) statt nur „Risiko“? [Gap, Plan §Risks]
+- [x] CHK031 Sind Security/Privacy-Anforderungen spezifiziert, welche foundation-object Daten sichtbar sein dürfen (IDs vs Names) und ob das tenant- & permission-scoped ist? [Gap, Spec §FR5]
+
+## Dependencies & Assumptions
+
+- [x] CHK032 Sind Abhängigkeiten zu Spec 040 (stable identifiers) und Spec 041 (UI navigation/detail pages) als Requirements eindeutig dokumentiert (hard requirement vs optional)? [Clarity, Plan §Dependencies]
+- [x] CHK033 Sind Annahmen über heterogene Reference-Shapes explizit dokumentiert und ist klar, wie neue Shapes in Scope aufgenommen werden (Change control / taxonomy update)? [Assumption, Plan §Risks]
+- [x] CHK034 Ist explizit dokumentiert, wann Edges extrahiert werden (im sync run vs post-processing), und wie Staleness/Refresh geregelt ist? [Gap, Spec §NFR1]
+
+## Ambiguities & Conflicts
+
+- [x] CHK035 Sind Begriffe „missing“, „not present“, „excluded“, „out-of-scope“ sauber definiert und konsistent verwendet (kein Vermischen von Datenzustand und Scope)? [Ambiguity, Spec §FR4, Out of Scope]
+- [x] CHK036 Ist klar, ob Filtering nur Relationship-Types betrifft oder auch Node-Types (Inventory vs Foundation) und ob beides kombinierbar sein soll? [Gap, Spec §Scenario 3]
+
+## Notes
+
+- Check items off as completed: `[x]`
+- Findings als kurze Stichpunkte direkt unter dem jeweiligen Item ergänzen
+- Jede `/speckit.checklist` Ausführung erzeugt eine neue Datei (kein Overwrite)
diff --git a/specs/042-inventory-dependencies-graph/checklists/requirements.md b/specs/042-inventory-dependencies-graph/checklists/requirements.md
new file mode 100644
index 0000000..0282beb
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/checklists/requirements.md
@@ -0,0 +1,37 @@
+# Requirements Checklist — Inventory Dependencies Graph (042)
+
+## Scope
+
+- [x] This checklist applies only to Spec 042 (Inventory Dependencies Graph).
+- [x] MVP scope: show **direct** inbound/outbound edges only (no depth>1 traversal / transitive blast radius).
+
+## Constitution Gates
+
+- [x] Inventory-first: edges derived from last-observed inventory data (no snapshot/backup side effects)
+- [x] Read/write separation: no Intune write paths introduced
+- [x] Single contract path to Graph: Graph access only via GraphClientInterface + contracts (if used)
+- [x] Tenant isolation: all reads/writes tenant-scoped
+- [x] Automation is idempotent & observable: unique key + upsert + run records + stable error codes
+- [x] Data minimization & safe logging: no secrets/tokens; avoid storing raw payloads outside allowed fields
+- [x] No new tables for warnings; warnings persist on InventorySyncRun.error_context.warnings[]
+
+## Functional Requirements Coverage
+
+- [x] FR-001 Relationship taxonomy exists and is testable (labels, directionality, descriptions)
+- [x] FR-002 Dependency edges stored in `inventory_links` with unique key (idempotent upsert)
+- [x] FR-003 Inbound/outbound query services tenant-scoped, limited (MVP: limit-only unless pagination is explicitly implemented)
+- [x] FR-004 Missing prerequisites represented as `target_type='missing'` with safe metadata + UI badge/tooltip
+- [x] FR-005 Relationship-type filtering available in UI (single-select, default “All”)
+
+## Non-Functional Requirements Coverage
+
+- [x] NFR-001 Idempotency: re-running extraction does not create duplicates; updates metadata deterministically
+- [x] NFR-002 Unknown reference shapes handled gracefully: warning recorded in run metadata; does not fail sync; no edge created for unsupported types
+
+## Tests (Pest)
+
+- [x] Extraction determinism + unique key (re-run equality)
+- [x] Missing edges show “Missing” badge and safe tooltip
+- [x] 50-edge limit enforced and truncation behavior is observable (if specified)
+- [x] Tenant isolation for queries and UI
+- [x] UI smoke: relationship-type filter limits visible edges
diff --git a/specs/042-inventory-dependencies-graph/contracts/README.md b/specs/042-inventory-dependencies-graph/contracts/README.md
new file mode 100644
index 0000000..0959125
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/contracts/README.md
@@ -0,0 +1,5 @@
+# Contracts — Inventory Dependencies Graph (042)
+
+This feature does not introduce a new public HTTP API in MVP (Filament page is server-rendered).
+
+The contracts in this folder describe the internal data shape passed from query/services to the UI rendering layer.
diff --git a/specs/042-inventory-dependencies-graph/contracts/dependency-edge.schema.json b/specs/042-inventory-dependencies-graph/contracts/dependency-edge.schema.json
new file mode 100644
index 0000000..922a2a2
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/contracts/dependency-edge.schema.json
@@ -0,0 +1,33 @@
+{
+  "$schema": "https://json-schema.org/draft/2020-12/schema",
+  "$id": "tenantpilot://contracts/042/dependency-edge.schema.json",
+  "title": "DependencyEdge",
+  "type": "object",
+  "additionalProperties": true,
+  "required": [
+    "tenant_id",
+    "source_type",
+    "source_id",
+    "target_type",
+    "relationship_type"
+  ],
+  "properties": {
+    "tenant_id": { "type": "integer" },
+    "source_type": { "type": "string", "enum": ["inventory_item", "foundation_object"] },
+    "source_id": { "type": "string" },
+    "target_type": { "type": "string", "enum": ["inventory_item", "foundation_object", "missing"] },
+    "target_id": { "type": ["string", "null"] },
+    "relationship_type": { "type": "string", "enum": ["assigned_to", "scoped_by", "targets", "depends_on"] },
+    "metadata": {
+      "type": ["object", "null"],
+      "additionalProperties": true,
+      "properties": {
+        "last_known_name": { "type": ["string", "null"] },
+        "raw_ref": {},
+        "foundation_type": { "type": "string", "enum": ["aad_group", "scope_tag", "device_category"] }
+      }
+    },
+    "created_at": { "type": ["string", "null"], "description": "ISO-8601 timestamp" },
+    "updated_at": { "type": ["string", "null"], "description": "ISO-8601 timestamp" }
+  }
+}
diff --git a/specs/042-inventory-dependencies-graph/data-model.md b/specs/042-inventory-dependencies-graph/data-model.md
new file mode 100644
index 0000000..61e7b7d
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/data-model.md
@@ -0,0 +1,72 @@
+# Data Model — Inventory Dependencies Graph (042)
+
+## Entities
+
+### InventoryItem
+Existing entity (Spec 040).
+
+Key fields used by this feature:
+- `tenant_id` (FK)
+- `external_id` (string; stable identifier used as edge endpoint)
+- `policy_type` (string)
+- `display_name` (nullable string)
+- `meta_jsonb` (array/jsonb; safe subset)
+
+### InventorySyncRun
+Existing entity used for observability of sync operations.
+
+Key fields used by this feature:
+- `tenant_id`
+- `selection_hash`
+- `selection_payload` (array)
+- `status` (running/success/partial/failed/skipped)
+- `had_errors` (bool)
+- `error_codes` (array)
+- `error_context` (array)
+
+For MVP warnings persistence:
+- `error_context.warnings[]` (array of warning objects)
+- Warning object shape (stable): `{type: 'unsupported_reference', policy_id, raw_ref, reason}`
+
+### InventoryLink
+Dependency edge storage.
+
+Fields:
+- `tenant_id`
+- `source_type` (string; MVP uses `inventory_item`)
+- `source_id` (string; stores `InventoryItem.external_id`)
+- `target_type` (string; `inventory_item` | `foundation_object` | `missing`)
+- `target_id` (nullable string; null when missing)
+- `relationship_type` (string; values from RelationshipType enum)
+- `metadata` (jsonb)
+- timestamps
+
+Unique key (idempotency):
+- `(tenant_id, source_type, source_id, target_type, target_id, relationship_type)`
+
+#### InventoryLink.metadata
+Common keys:
+- `last_known_name` (nullable string)
+- `raw_ref` (mixed/array; only when safe)
+
+Required when `target_type='foundation_object'`:
+- `foundation_type` (string enum-like): `aad_group` | `scope_tag` | `device_category`
+
+## Enums
+
+### RelationshipType
+- `assigned_to`
+- `scoped_by`
+- `targets`
+- `depends_on`
+
+## Relationships
+
+- InventoryItem (source) has many outbound InventoryLinks via `source_id` + `tenant_id`.
+- InventoryItem (target) has many inbound InventoryLinks via `target_id` + `tenant_id` where `target_type='inventory_item'`.
+
+## Constraints / Limits
+
+- Query: limit-only, ordered by `created_at DESC`.
+- UI: max 50 per direction (<=100 combined).
+- Extraction: max 50 outbound edges per item; unknown shapes are warning-only.
diff --git a/specs/042-inventory-dependencies-graph/plan.md b/specs/042-inventory-dependencies-graph/plan.md
index bf86ce3..4bab182 100644
--- a/specs/042-inventory-dependencies-graph/plan.md
+++ b/specs/042-inventory-dependencies-graph/plan.md
@@ -1,24 +1,100 @@
-# Implementation Plan: Inventory Dependencies Graph
+# Implementation Plan: Inventory Dependencies Graph (042)
 
-**Date**: 2026-01-07  
-**Spec**: `specs/042-inventory-dependencies-graph/spec.md`
+**Branch**: `feat/042-inventory-dependencies-graph` | **Date**: 2026-01-10 | **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.
+Provide a read-only dependency view for an Inventory Item (direct inbound/outbound edges) with filters for direction and relationship type. Dependencies are derived from inventory sync payloads and stored idempotently in `inventory_links`.
 
-## Dependencies
+## MVP Constraints (Explicit)
 
-- Inventory items and stable identifiers (Spec 040)
-- Inventory UI detail pages (Spec 041) or equivalent navigation
+- Direct neighbors only (no depth > 1 traversal / transitive blast radius).
+- Limit-only queries (no pagination/cursors).
+- UI shows <= 50 edges per direction (<= 100 total when showing both directions).
+- Unknown/unsupported reference shapes are warning-only (no edge created).
+- Warnings persist on `InventorySyncRun.error_context.warnings[]`.
+- No new tables for warnings.
 
-## Deliverables
+## Technical Context
 
-- Relationship taxonomy
-- Persisted dependency edges
-- Query and rendering in UI
+**Language/Version**: PHP 8.4.x
+**Primary Dependencies**: Laravel 12, Filament v4, Livewire v3
+**Storage**: PostgreSQL (JSONB)
+**Testing**: Pest v4
+**Target Platform**: Web (Filament admin)
+**Project Type**: Laravel monolith
+**Performance Goals**: dependency section renders in <2s with indexed + limited queries
+**Constraints**: tenant scoped only; no extra Graph lookups for enrichment
+**Scale/Scope**: edge rendering and extraction are hard-capped
 
-## Risks
+## Constitution Check
 
-- Heterogeneous reference shapes across policy types
-- Edge explosion for large tenants
+*GATE: Must pass before Phase 0 research. Re-check after Phase 1 design.*
+
+- Inventory-first: edges reflect last observed sync payloads; no backups/snapshots.
+- Read/write separation: UI is read-only; no Intune write paths.
+- Single contract path to Graph: no new Graph calls for this feature.
+- Tenant isolation: all edges stored/queried with `tenant_id`.
+- Automation: idempotent via unique key + upsert; observable via run record; warnings persisted.
+- Data minimization: only metadata stored; no secrets/tokens.
+
+Gate status: PASS.
+
+## Project Structure
+
+### Documentation (this feature)
+
+```text
+specs/042-inventory-dependencies-graph/
+├── plan.md
+├── spec.md
+├── tasks.md
+├── research.md
+├── data-model.md
+├── quickstart.md
+├── contracts/
+│   ├── README.md
+│   └── dependency-edge.schema.json
+└── checklists/
+    ├── pr-gate.md
+    └── requirements.md
+```
+
+### Source Code (repository root)
+
+```text
+app/Filament/Resources/InventoryItemResource.php
+app/Models/InventoryItem.php
+app/Models/InventoryLink.php
+app/Models/InventorySyncRun.php
+app/Services/Inventory/DependencyExtractionService.php
+app/Services/Inventory/DependencyQueryService.php
+app/Support/Enums/RelationshipType.php
+resources/views/filament/components/dependency-edges.blade.php
+tests/Feature/InventoryItemDependenciesTest.php
+tests/Feature/DependencyExtractionFeatureTest.php
+tests/Unit/DependencyExtractionServiceTest.php
+```
+
+## Phase 0: Research (Output: research.md)
+
+Document decisions + rationale + alternatives for MVP clarifications (limit-only, 50 per direction, warnings-on-run-record, warning-only unknown shapes, required foundation_type metadata, relationship-type filter).
+
+## Phase 1: Design (Outputs: data-model.md, contracts/*, quickstart.md)
+
+- Data model: entities and fields, including `inventory_links` unique key and metadata shapes.
+- Contracts: JSON schema describing the dependency edge data passed to the UI.
+- Quickstart: how to view dependencies and run targeted tests.
+
+## Phase 2: Implementation Plan (MVP)
+
+1. UI filters: direction + relationship-type via querystring.
+2. Query: use DB filtering via `DependencyQueryService` optional `relationship_type`.
+3. Extraction: align unknown/unsupported shapes to warning-only and persist warnings on run record.
+4. Tests: add/adjust unit/feature/UI smoke tests for relationship filtering and warning-only behavior.
+5. Quality gates: Pint + targeted Pest tests.
+
+## Complexity Tracking
+
+None for MVP (no constitution violations).
+| [e.g., Repository pattern] | [specific problem] | [why direct DB access insufficient] |
diff --git a/specs/042-inventory-dependencies-graph/quickstart.md b/specs/042-inventory-dependencies-graph/quickstart.md
new file mode 100644
index 0000000..7555a72
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/quickstart.md
@@ -0,0 +1,34 @@
+# Quickstart — Inventory Dependencies Graph (042)
+
+## Prerequisites
+
+- Run the app via Sail.
+- Ensure you have at least one tenant and inventory items.
+
+## Viewing Dependencies
+
+1. Navigate to **Inventory** → select an Inventory Item.
+2. In the **Dependencies** section use the querystring-backed filters:
+
+- `direction`: `all` (default) | `inbound` | `outbound`
+- `relationship_type`: `all` (default) | `assigned_to` | `scoped_by` | `targets` | `depends_on`
+
+Example URLs:
+- `...?direction=outbound&relationship_type=scoped_by`
+
+## Running the Targeted Tests
+
+- UI smoke tests:
+  - `./vendor/bin/sail artisan test tests/Feature/InventoryItemDependenciesTest.php`
+
+## MVP Notes
+
+- Limit-only, no pagination.
+- Shows <=50 edges per direction (<=100 total when showing both directions).
+- Unknown/unsupported reference shapes are warning-only and should be visible via `InventorySyncRun.error_context.warnings[]`.
+
+## Manual Performance Check (<2s)
+
+1. Open an Inventory Item with ~50 inbound and/or ~50 outbound edges.
+2. Use browser devtools Network tab to confirm the page request completes quickly.
+3. Toggle `direction` and `relationship_type` filters and confirm responses remain fast.
diff --git a/specs/042-inventory-dependencies-graph/research.md b/specs/042-inventory-dependencies-graph/research.md
new file mode 100644
index 0000000..41e5a45
--- /dev/null
+++ b/specs/042-inventory-dependencies-graph/research.md
@@ -0,0 +1,47 @@
+# Research — Inventory Dependencies Graph (042)
+
+This document resolves all implementation clarifications for the MVP and records the key decisions with rationale and alternatives.
+
+## Decisions
+
+### 1) Pagination vs limit-only
+- Decision: **Limit-only** (no pagination/cursors in MVP).
+- Rationale: Pagination introduces cursor semantics, UI states, sorting guarantees, and additional tests; MVP goal is fast/stable/testable.
+- Alternatives considered:
+  - Add pagination now: rejected due to complexity and low MVP value.
+
+### 2) Edge limits in UI
+- Decision: **50 per direction** (inbound and outbound), so up to **100 total** when showing both directions.
+- Rationale: Keeps each query bounded and predictable; matches existing UI composition (combine inbound + outbound).
+- Alternatives considered:
+  - 50 total across both directions: rejected because it makes results direction-dependent and less intuitive.
+
+### 3) Relationship-type filter (UI)
+- Decision: Add **single-select Relationship filter** with default **All**; persists in querystring.
+- Rationale: Small UX improvement with high usefulness; minimal risk.
+- Alternatives considered:
+  - No relationship filter: rejected (spec requires it; improves scanability).
+
+### 4) Unknown/unsupported reference shapes
+- Decision: **Warning-only** (no edge created).
+- Rationale: Creating “missing” edges for unknown shapes is misleading; it inflates perceived missing prerequisites and reduces trust.
+- Alternatives considered:
+  - Create missing edge: rejected as potentially inaccurate.
+
+### 5) Where warnings are stored
+- Decision: Persist warnings on the **sync run record** at `InventorySyncRun.error_context.warnings[]`.
+- Rationale: Auditable, debuggable, no new schema, consistent with “observable automation”.
+- Alternatives considered:
+  - Per-item warnings in `InventoryItem.meta_jsonb`: rejected (pollutes inventory, harder to reason about run-level issues).
+  - New warnings table: rejected (migrations/models/retention/cleanup burden).
+
+### 6) Foundation object typing
+- Decision: For `target_type='foundation_object'`, always store `metadata.foundation_type`.
+- Rationale: Deterministic UI labeling/resolution; avoids inference.
+- Alternatives considered:
+  - Infer foundation type from relationship type: rejected (brittle).
+
+## Notes / Implementation Implications
+
+- If the current code path creates missing edges for unknown assignment shapes, it must be adjusted to **warning-only** to match spec.
+- Warning payload shape should be stable: `{type: 'unsupported_reference', policy_id, raw_ref, reason}`.
diff --git a/specs/042-inventory-dependencies-graph/spec.md b/specs/042-inventory-dependencies-graph/spec.md
index 6abb63f..9ba0913 100644
--- a/specs/042-inventory-dependencies-graph/spec.md
+++ b/specs/042-inventory-dependencies-graph/spec.md
@@ -8,6 +8,24 @@ ## Purpose
 
 Represent and surface dependency relationships between inventory items and foundational Intune objects so admins can understand blast radius and prerequisites.
 
+MVP shows direct inbound/outbound edges only; depth > 1 traversal is out of scope for this iteration.
+
+## Clarifications
+
+### Session 2026-01-10
+
+- Q: Should FR3 be paginated or limit-only for MVP? → A: Limit-only (no pagination).
+- Q: Where should unknown/unsupported reference warnings be persisted? → A: On the inventory sync run record (e.g., `InventorySyncRun.error_context.warnings[]`).
+- Q: For unknown assignment target shapes, should we create a missing edge or warning-only? → A: Warning-only (no edge created).
+- Q: Should `foundation_object` edges always store `metadata.foundation_type`? → A: Yes (required).
+- Q: Should the UI show 50 edges total or 50 per direction? → A: 50 per direction (up to 100 total when showing both directions).
+
+**Definitions**:
+- **Blast radius**: All resources directly affected by a change to a given item (outbound edges only; no transitive traversal in MVP).
+- **Prerequisite**: A hard dependency required for an item to function; missing prerequisites are explicitly surfaced.
+- **Inbound edge**: A relationship pointing TO this item (e.g., "Policy A is assigned to Group X" → Group X has inbound edge from Policy A).
+- **Outbound edge**: A relationship pointing FROM this item (e.g., "Policy A is scoped by ScopeTag Y" → Policy A has outbound edge to ScopeTag Y).
+
 ## User Scenarios & Testing
 
 ### Scenario 1: View dependencies for an item
@@ -18,30 +36,132 @@ ### Scenario 1: View dependencies for an item
 ### 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
+- Then missing prerequisites are clearly indicated (red badge, "Missing" label, tooltip with last-known displayName if available)
 
-### Scenario 3: Filter dependencies by relationship type
+### Scenario 3: Zero dependencies
+- Given an item has no inbound or outbound edges
+- When the user opens dependencies view
+- Then a "No dependencies found" message is shown
+
+### Scenario 4: Filter dependencies by relationship type
 - Given multiple relationship types exist
-- When the user filters by relationship type
-- Then only matching edges are shown
+- When the user filters by relationship type (single-select dropdown, default: "All")
+- Then only matching edges are shown (empty selection = all edges visible)
+
+### Scenario 5: Only missing prerequisites
+- Given an item where all referenced targets are unresolved (no matching inventory or foundation objects)
+- When the user opens the dependencies view and selects "Outbound" or "All"
+- Then all shown edges are annotated as "Missing" with a red badge and tooltip; filtering still works and zero resolvable targets do not error
 
 ## 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.
+- **FR1: Relationship taxonomy**  
+  Define a normalized set of relationship types covering inventory→inventory and inventory→foundation edges.  
+  Supported types (MVP):
+  - `assigned_to` (Policy → AAD Group)
+  - `scoped_by` (Policy → Scope Tag)
+  - `targets` (Update Policy → Device Category, conditional logic)
+  - `depends_on` (Generic prerequisite, e.g., Compliance Policy referenced by Conditional Access)
+  
+  Each type has:
+  - `name` (string, e.g., "assigned_to")
+  - `display_label` (string, e.g., "Assigned to")
+  - `directionality` (enum: `outbound`, `inbound`, `bidirectional`)
+  - `description` (brief explanation)
+
+ - **FR2: Dependency edge storage**  
+  Store edges in an `inventory_links` table with fields:
+  - `id` (PK)
+  - `tenant_id` (FK, indexed)
+  - `source_type` (string: `inventory_item`, `foundation_object`)
+  - `source_id` (UUID or stable ref)
+  - `target_type` (string: `inventory_item`, `foundation_object`, `missing`)
+  - `target_id` (UUID or stable ref, nullable if missing)
+  - `relationship_type` (FK to taxonomy or enum)
+  - `metadata` (JSONB, optional: last_known_name, raw_ref, etc.; for `target_type='foundation_object'`, `metadata.foundation_type` is required)
+  - `created_at`, `updated_at`
+  
+  **In-scope foundation object types (MVP)**:
+  - AAD Groups (`aad_group`)
+  - Scope Tags (`scope_tag`)
+  - Device Categories (`device_category`)
+  
+  **Out-of-scope foundation types** (for this iteration): Conditional Access Policies, Compliance Policies as foundation nodes (only as inventory items).
+
+- **FR3: Query inbound/outbound edges**  
+  Provide service methods:
+  - `getOutboundEdges(item_id, relationship_type?, limit=50)` → returns edges where item is source
+  - `getInboundEdges(item_id, relationship_type?, limit=50)` → returns edges where item is target
+  
+  Both return up to `limit` edges, ordered by `created_at DESC`.
+
+  UI supports filtering by `relationship_type` via a single-select dropdown (default: "All"; empty selection behaves as "All").
+
+- **FR4: Missing prerequisites**  
+  When a target reference cannot be resolved:
+  - Create edge with `target_type='missing'`, `target_id=null`
+  - Store `metadata.last_known_name` and `metadata.raw_ref` if available
+  - UI displays "Missing" badge + tooltip
+  
+  No separate "deleted" or "archived" state in core inventory; missing is purely an edge property.
+
+  Unknown/unsupported reference shapes do not create edges; they are handled via warnings (see NFR2).
+
+- **FR5: Tenant scoping and access control**  
+  - All edges filtered by `tenant_id` matching `Tenant::current()`
+  - Read access: any authenticated tenant user
+  - No cross-tenant queries allowed (enforced at query builder level)
 
 ## 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.
+- **NFR1: Idempotency**  
+  Dependency extraction must be idempotent:
+  - Unique key: `(tenant_id, source_type, source_id, target_type, target_id, relationship_type)`
+  - On re-run: upsert (update `updated_at`, replace `metadata` if changed)
+  - Orphan edges (source/target no longer in inventory) are NOT auto-deleted; cleanup is manual or scheduled separately
+
+- **NFR2: Graceful unknown-reference handling**  
+  If an unknown/unsupported reference shape is encountered:
+  - Log warning with severity `info` (not `error`)
+  - Do NOT create an edge for unsupported types (including unknown assignment target shapes)
+  - Record warning in sync run metadata at `InventorySyncRun.error_context.warnings[]` with shape: `{type: 'unsupported_reference', policy_id, raw_ref, reason}`
+  - Sync run continues without failure
+
+## Graph Traversal & Cycles (Out of Scope for MVP)
+
+- Depth > 1 traversal (transitive “blast radius”) is out of scope for this iteration.
+- The UI shows only direct inbound/outbound edges.
+- Future work may add depth-capped traversal with cycle handling and explicit cycle visualization.
 
 ## 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).
+- **SC1: Blast radius determination**  
+  Admins can determine prerequisites (inbound edges) and blast radius (outbound edges; direct only) for any item in under 2 minutes:
+  - Measured from: clicking "View Dependencies" on an item detail page
+  - To: able to answer "What would break if I delete this?" and "What does this depend on?"
+  - Acceptance: <2s page load, ≤50 edges per direction shown initially (≤100 total when showing both directions), clear visual grouping by relationship type
+
+- **SC2: Deterministic output**  
+  For supported relationship types, dependency edges are consistent across re-runs:
+  - Given identical inventory state (same items, same Graph API responses)
+  - Edge set equality: same `(source, target, relationship_type)` tuples (order-independent)
+  - Acceptance: automated test re-runs extraction twice on fixed test data; assert edge sets match (ignoring `updated_at`)
+
+## Security & Privacy
+
+- All data is tenant-scoped; no cross-tenant queries or joins.
+- Foundation object visibility:
+  - Display name shown only if available from tenant-authorized sources (inventory metadata or prior sync payloads).
+  - If not available, show a masked or abbreviated identifier (e.g., first 6 characters of ID) with no external lookup.
+- Stored metadata for edges must avoid PII beyond display names surfaced by Graph within the tenant; raw references may be stored but not enriched from outside the tenant scope.
+
+## Traceability
+
+- FR1 (taxonomy) → SC2 (deterministic types), tests: unit taxonomy load/assert
+- FR2 (storage) → SC2 (edge equality), tests: feature upsert and equality
+- FR3 (queries) → SC1 (answer in <2 min), tests: service returns inbound/outbound within limits
+- FR4 (missing) → SC1 (clear prerequisite view), tests: feature missing badge/tooltip
+- FR5 (tenant scope) → SC1/SC2 (correct data, deterministic set), tests: tenant isolation
 
 ## Out of Scope
 
diff --git a/specs/042-inventory-dependencies-graph/tasks.md b/specs/042-inventory-dependencies-graph/tasks.md
index 22c952b..780e294 100644
--- a/specs/042-inventory-dependencies-graph/tasks.md
+++ b/specs/042-inventory-dependencies-graph/tasks.md
@@ -1,7 +1,198 @@
-# Tasks: Inventory Dependencies Graph
+# Tasks: Inventory Dependencies Graph (042)
 
-- [ ] 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
+**Input**: Design documents in `specs/042-inventory-dependencies-graph/` (plan.md, spec.md, research.md, data-model.md, contracts/, quickstart.md)
+
+**Notes**
+- Tasks are grouped by user story so each story is independently testable.
+- Tests are included because this feature affects runtime behavior.
+- MVP constraints (direct only, limit-only, 50 per direction, warnings-on-run-record, no warnings tables) must remain enforced.
+
+## Phase 1: Setup (Shared)
+
+**Purpose**: Ensure feature docs and scope constraints are locked before code changes.
+
+- [x] T001 Validate MVP constraints in `specs/042-inventory-dependencies-graph/plan.md` remain aligned with `specs/042-inventory-dependencies-graph/spec.md`
+- [x] T002 Validate scope + NFR checkboxes in `specs/042-inventory-dependencies-graph/checklists/requirements.md` cover all accepted MVP constraints
+
+---
+
+## Phase 2: Foundational (Blocking Prerequisites)
+
+**Purpose**: Storage + extraction + query services that all UI stories rely on.
+
+**Checkpoint**: After Phase 2, edges can be extracted and queried tenant-safely with limits.
+
+- [ ] T003 [P] Ensure relationship types and labels are centralized in `app/Support/Enums/RelationshipType.php`
+- [ ] T004 Ensure `inventory_links` schema (unique key + indexes) matches spec in `database/migrations/2026_01_07_150000_create_inventory_links_table.php`
+- [ ] T005 [P] Ensure `InventoryLink` casts and tenant-safe query patterns in `app/Models/InventoryLink.php`
+- [ ] T006 [P] Ensure factory coverage for dependency edges in `database/factories/InventoryLinkFactory.php`
+- [ ] T007 Align idempotent upsert semantics for edges in `app/Services/Inventory/DependencyExtractionService.php`
+- [ ] T008 Implement warning-only handling for unknown/unsupported reference shapes in `app/Services/Inventory/DependencyExtractionService.php`
+- [ ] T009 Persist warnings on the sync run record at `InventorySyncRun.error_context.warnings[]` via `app/Services/Inventory/InventorySyncService.php`
+- [ ] T010 Implement limit-only inbound/outbound queries with optional relationship filter in `app/Services/Inventory/DependencyQueryService.php` (ordered by `created_at DESC`)
+- [ ] T011 [P] Add determinism + idempotency tests in `tests/Unit/DependencyExtractionServiceTest.php`
+- [ ] T012 [P] Add tenant isolation tests for queries in `tests/Feature/DependencyExtractionFeatureTest.php`
+- [x] T003 [P] Ensure relationship types and labels are centralized in `app/Support/Enums/RelationshipType.php`
+- [x] T004 Ensure `inventory_links` schema (unique key + indexes) matches spec in `database/migrations/2026_01_07_150000_create_inventory_links_table.php`
+- [x] T005 [P] Ensure `InventoryLink` casts and tenant-safe query patterns in `app/Models/InventoryLink.php`
+- [x] T006 [P] Ensure factory coverage for dependency edges in `database/factories/InventoryLinkFactory.php`
+- [x] T007 Align idempotent upsert semantics for edges in `app/Services/Inventory/DependencyExtractionService.php`
+- [x] T008 Implement warning-only handling for unknown/unsupported reference shapes in `app/Services/Inventory/DependencyExtractionService.php`
+- [x] T009 Persist warnings on the sync run record at `InventorySyncRun.error_context.warnings[]` via `app/Services/Inventory/InventorySyncService.php`
+- [x] T010 Implement limit-only inbound/outbound queries with optional relationship filter in `app/Services/Inventory/DependencyQueryService.php` (ordered by `created_at DESC`)
+- [x] T011 [P] Add determinism + idempotency tests in `tests/Unit/DependencyExtractionServiceTest.php`
+- [x] T012 [P] Add tenant isolation tests for queries in `tests/Feature/DependencyExtractionFeatureTest.php`
+
+---
+
+## Phase 3: User Story 1 — View Dependencies (Priority: P1) 🎯 MVP
+
+**Goal**: As an admin, I can view direct inbound/outbound dependencies for an inventory item.
+
+**Independent Test**: Opening an Inventory Item shows a Dependencies section that renders within limits and supports direction filtering.
+
+- [ ] T013 [P] [US1] Wire dependencies section into Filament item view in `app/Filament/Resources/InventoryItemResource.php`
+- [ ] T014 [P] [US1] Render edges grouped by relationship type in `resources/views/filament/components/dependency-edges.blade.php`
+- [ ] T015 [US1] Add direction filter (querystring-backed) in `resources/views/filament/components/dependency-edges.blade.php`
+- [ ] T016 [US1] Parse/validate `direction` and pass to query service in `app/Filament/Resources/InventoryItemResource.php`
+- [ ] T017 [US1] Add UI smoke test for dependencies rendering + direction filter in `tests/Feature/InventoryItemDependenciesTest.php`
+- [x] T013 [P] [US1] Wire dependencies section into Filament item view in `app/Filament/Resources/InventoryItemResource.php`
+- [x] T014 [P] [US1] Render edges grouped by relationship type in `resources/views/filament/components/dependency-edges.blade.php`
+- [x] T015 [US1] Add direction filter (querystring-backed) in `resources/views/filament/components/dependency-edges.blade.php`
+- [x] T016 [US1] Parse/validate `direction` and pass to query service in `app/Filament/Resources/InventoryItemResource.php`
+- [x] T017 [US1] Add UI smoke test for dependencies rendering + direction filter in `tests/Feature/InventoryItemDependenciesTest.php`
+
+---
+
+## Phase 4: User Story 2 — Identify Missing Prerequisites (Priority: P2)
+
+**Goal**: As an admin, I can clearly see when a referenced prerequisite object is missing.
+
+**Independent Test**: A missing target renders a red “Missing” badge and safe tooltip using `metadata.last_known_name`/`metadata.raw_ref`.
+
+- [ ] T018 [US2] Ensure unresolved targets create `target_type='missing'` edges with safe metadata in `app/Services/Inventory/DependencyExtractionService.php`
+- [ ] T019 [US2] Display “Missing” badge + tooltip for missing edges in `resources/views/filament/components/dependency-edges.blade.php`
+- [ ] T020 [US2] Add feature test for missing edge creation + metadata in `tests/Feature/DependencyExtractionFeatureTest.php`
+- [ ] T021 [US2] Add UI test asserting missing badge/tooltip is visible in `tests/Feature/InventoryItemDependenciesTest.php`
+- [x] T018 [US2] Ensure unresolved targets create `target_type='missing'` edges with safe metadata in `app/Services/Inventory/DependencyExtractionService.php`
+- [x] T019 [US2] Display “Missing” badge + tooltip for missing edges in `resources/views/filament/components/dependency-edges.blade.php`
+- [x] T020 [US2] Add feature test for missing edge creation + metadata in `tests/Feature/DependencyExtractionFeatureTest.php`
+- [x] T021 [US2] Add UI test asserting missing badge/tooltip is visible in `tests/Feature/InventoryItemDependenciesTest.php`
+
+---
+
+## Phase 5: User Story 3 — Filter By Relationship Type (Priority: P2)
+
+**Goal**: As an admin, I can filter dependencies by relationship type to reduce noise.
+
+**Independent Test**: Selecting a relationship type shows only matching edges; default “All” shows everything.
+
+- [ ] T022 [US3] Add relationship-type dropdown filter (querystring-backed) in `resources/views/filament/components/dependency-edges.blade.php`
+- [ ] T023 [US3] Parse/validate `relationship_type` and pass to query service in `app/Filament/Resources/InventoryItemResource.php`
+- [ ] T024 [US3] Add UI smoke test verifying relationship filter limits edges in `tests/Feature/InventoryItemDependenciesTest.php`
+- [x] T022 [US3] Add relationship-type dropdown filter (querystring-backed) in `resources/views/filament/components/dependency-edges.blade.php`
+- [x] T023 [US3] Parse/validate `relationship_type` and pass to query service in `app/Filament/Resources/InventoryItemResource.php`
+- [x] T024 [US3] Add UI smoke test verifying relationship filter limits edges in `tests/Feature/InventoryItemDependenciesTest.php`
+
+---
+
+## Phase 6: User Story 4 — Zero Dependencies (Priority: P3)
+
+**Goal**: As an admin, I get a clear empty state when no dependencies exist.
+
+**Independent Test**: When queries return zero edges, the UI shows “No dependencies found” and does not error.
+
+- [ ] T025 [US4] Render zero-state message in `resources/views/filament/components/dependency-edges.blade.php`
+- [ ] T026 [US4] Add UI test for zero-state rendering in `tests/Feature/InventoryItemDependenciesTest.php`
+- [x] T025 [US4] Render zero-state message in `resources/views/filament/components/dependency-edges.blade.php`
+- [x] T026 [US4] Add UI test for zero-state rendering in `tests/Feature/InventoryItemDependenciesTest.php`
+
+---
+
+## Phase 7: Polish & Cross-Cutting Concerns
+
+**Purpose**: Tighten docs/contracts and run quality gates.
+
+- [ ] T027 [P] Align filter docs + URLs in `specs/042-inventory-dependencies-graph/quickstart.md`
+- [ ] T028 [P] Ensure schema reflects metadata requirements in `specs/042-inventory-dependencies-graph/contracts/dependency-edge.schema.json`
+- [ ] T029 Update requirement-gate checkboxes in `specs/042-inventory-dependencies-graph/checklists/pr-gate.md`
+- [ ] T030 Run Pint and fix formatting in `app/`, `resources/views/filament/components/`, and `tests/` (touching `app/Support/Enums/RelationshipType.php`, `resources/views/filament/components/dependency-edges.blade.php`, `tests/Feature/InventoryItemDependenciesTest.php`)
+- [ ] T031 Run targeted tests: `tests/Feature/InventoryItemDependenciesTest.php`, `tests/Feature/DependencyExtractionFeatureTest.php`, `tests/Unit/DependencyExtractionServiceTest.php`
+- [x] T027 [P] Align filter docs + URLs in `specs/042-inventory-dependencies-graph/quickstart.md`
+- [x] T028 [P] Ensure schema reflects metadata requirements in `specs/042-inventory-dependencies-graph/contracts/dependency-edge.schema.json`
+- [x] T029 Update requirement-gate checkboxes in `specs/042-inventory-dependencies-graph/checklists/pr-gate.md`
+- [x] T030 Run Pint and fix formatting in `app/`, `resources/views/filament/components/`, and `tests/` (touching `app/Support/Enums/RelationshipType.php`, `resources/views/filament/components/dependency-edges.blade.php`, `tests/Feature/InventoryItemDependenciesTest.php`)
+- [x] T031 Run targeted tests: `tests/Feature/InventoryItemDependenciesTest.php`, `tests/Feature/DependencyExtractionFeatureTest.php`, `tests/Unit/DependencyExtractionServiceTest.php`
+
+---
+
+## Phase 8: Consistency & Security Coverage (Cross-Cutting)
+
+**Purpose**: Close remaining spec→tasks gaps (ordering, masking, auth expectations, logging severity).
+
+- [ ] T032 [P] Add test asserting inbound/outbound query ordering by `created_at DESC` + limit-only behavior in `tests/Feature/DependencyExtractionFeatureTest.php` (or `tests/Unit/DependencyExtractionServiceTest.php` if more appropriate)
+- [ ] T033 [US2] Implement masked/abbreviated identifier rendering when `metadata.last_known_name` is null in `resources/views/filament/components/dependency-edges.blade.php`
+- [ ] T034 [US2] Add UI test for masked identifier behavior in `tests/Feature/InventoryItemDependenciesTest.php`
+- [ ] T035 [P] Add auth behavior test for the inventory item dependencies view (guest blocked; authenticated tenant user allowed) in `tests/Feature/InventoryItemDependenciesTest.php`
+- [ ] T036 [P] Ensure unknown/unsupported reference warnings are logged at `info` severity in `app/Services/Inventory/DependencyExtractionService.php` and add a unit test using `Log::fake()` in `tests/Unit/DependencyExtractionServiceTest.php`
+- [ ] T037 Document how to verify the <2s dependency section goal (manual acceptance check) in `specs/042-inventory-dependencies-graph/quickstart.md`
+- [x] T032 [P] Add test asserting inbound/outbound query ordering by `created_at DESC` + limit-only behavior in `tests/Feature/DependencyExtractionFeatureTest.php` (or `tests/Unit/DependencyExtractionServiceTest.php` if more appropriate)
+- [x] T033 [US2] Implement masked/abbreviated identifier rendering when `metadata.last_known_name` is null in `resources/views/filament/components/dependency-edges.blade.php`
+- [x] T034 [US2] Add UI test for masked identifier behavior in `tests/Feature/InventoryItemDependenciesTest.php`
+- [x] T035 [P] Add auth behavior test for the inventory item dependencies view (guest blocked; authenticated tenant user allowed) in `tests/Feature/InventoryItemDependenciesTest.php`
+- [x] T036 [P] Ensure unknown/unsupported reference warnings are logged at `info` severity in `app/Services/Inventory/DependencyExtractionService.php` and add a unit test using `Log::fake()` in `tests/Unit/DependencyExtractionServiceTest.php`
+- [x] T037 Document how to verify the <2s dependency section goal (manual acceptance check) in `specs/042-inventory-dependencies-graph/quickstart.md`
+
+---
+
+## Dependencies & Execution Order
+
+### Phase Dependencies
+
+- Phase 1 (Setup) → Phase 2 (Foundational) → US1 (MVP) → US2/US3 → US4 → Polish
+
+### User Story Dependencies
+
+- US1 depends on Phase 2.
+- US2 depends on Phase 2 and US1 (needs the Dependencies view).
+- US3 depends on Phase 2 and US1 (needs the Dependencies view).
+- US4 depends on US1 (zero-state is part of the Dependencies view).
+
+## Parallel Execution Examples
+
+### Phase 2 (Foundational)
+
+- [P] `app/Support/Enums/RelationshipType.php` and `database/migrations/2026_01_07_150000_create_inventory_links_table.php`
+- [P] `database/factories/InventoryLinkFactory.php` and `tests/Unit/DependencyExtractionServiceTest.php`
+
+### User Story 1 (US1)
+
+- [P] Update `app/Filament/Resources/InventoryItemResource.php` while implementing rendering in `resources/views/filament/components/dependency-edges.blade.php`
+
+### User Story 2 (US2)
+
+- [P] Implement missing-edge extraction in `app/Services/Inventory/DependencyExtractionService.php` while updating UI rendering in `resources/views/filament/components/dependency-edges.blade.php`
+
+### User Story 3 (US3)
+
+- [P] Implement relationship dropdown in `resources/views/filament/components/dependency-edges.blade.php` while wiring query parsing in `app/Filament/Resources/InventoryItemResource.php`
+
+### User Story 4 (US4)
+
+- [P] Implement zero-state UI in `resources/views/filament/components/dependency-edges.blade.php` while writing the UI assertion in `tests/Feature/InventoryItemDependenciesTest.php`
+
+## Implementation Strategy
+
+### MVP First (US1 Only)
+
+1. Complete Phase 1 and Phase 2.
+2. Implement US1 and validate with `tests/Feature/InventoryItemDependenciesTest.php`.
+3. Stop and demo MVP UI before proceeding to US2/US3.
+
+### Incremental Delivery
+
+1. Phase 1 + Phase 2 → foundation ready.
+2. US1 → demo dependency view.
+3. US2 → add missing-prerequisite trust signals.
+4. US3 → add relationship filtering for readability.
+5. US4 → refine empty-state UX.
diff --git a/tests/Feature/DependencyExtractionFeatureTest.php b/tests/Feature/DependencyExtractionFeatureTest.php
new file mode 100644
index 0000000..cbfc0ac
--- /dev/null
+++ b/tests/Feature/DependencyExtractionFeatureTest.php
@@ -0,0 +1,275 @@
+<?php
+
+use App\Models\InventoryItem;
+use App\Models\InventoryLink;
+use App\Models\Tenant;
+use App\Services\Graph\GraphClientInterface;
+use App\Services\Graph\GraphResponse;
+use App\Services\Inventory\DependencyQueryService;
+use App\Services\Inventory\InventorySyncService;
+
+class FakeGraphClientForDeps implements GraphClientInterface
+{
+    public function listPolicies(string $policyType, array $options = []): GraphResponse
+    {
+        return new GraphResponse(true, [
+            [
+                'id' => 'pol-1',
+                'displayName' => 'Test Policy',
+                'assignments' => [
+                    ['target' => ['groupId' => 'group-1']],
+                    ['target' => ['groupId' => 'group-2']],
+                ],
+                'roleScopeTagIds' => ['scope-tag-1', 'scope-tag-2'],
+            ],
+        ], 200);
+    }
+
+    public function getPolicy(string $policyType, string $policyId, array $options = []): GraphResponse
+    {
+        return new GraphResponse(true, [], 200);
+    }
+
+    public function getOrganization(array $options = []): GraphResponse
+    {
+        return new GraphResponse(true, [], 200);
+    }
+
+    public function applyPolicy(string $policyType, string $policyId, array $payload, array $options = []): GraphResponse
+    {
+        return new GraphResponse(true, [], 200);
+    }
+
+    public function getServicePrincipalPermissions(array $options = []): GraphResponse
+    {
+        return new GraphResponse(true, [], 200);
+    }
+
+    public function request(string $method, string $path, array $options = []): GraphResponse
+    {
+        return new GraphResponse(true, [], 200);
+    }
+}
+
+it('extracts edges during inventory sync and marks missing appropriately', function () {
+    $tenant = Tenant::factory()->create();
+    $this->app->bind(GraphClientInterface::class, fn () => new FakeGraphClientForDeps);
+
+    $svc = app(InventorySyncService::class);
+
+    $run = $svc->syncNow($tenant, [
+        'policy_types' => ['deviceConfiguration'],
+        'categories' => [],
+        'include_foundations' => false,
+        'include_dependencies' => true,
+    ]);
+
+    expect($run->status)->toBe('success');
+
+    $edges = InventoryLink::query()->where('tenant_id', $tenant->getKey())->get();
+    // 2 assigned_to + 2 scoped_by = 4
+    expect($edges->count())->toBe(4);
+});
+
+it('respects 50-edge limit for outbound extraction', function () {
+    $tenant = Tenant::factory()->create();
+    // Fake client returning 60 group assignments
+    $this->app->bind(GraphClientInterface::class, function () {
+        return new class implements GraphClientInterface
+        {
+            public function listPolicies(string $policyType, array $options = []): GraphResponse
+            {
+                $assignments = [];
+                for ($i = 1; $i <= 60; $i++) {
+                    $assignments[] = ['target' => ['groupId' => 'g-'.$i]];
+                }
+
+                return new GraphResponse(true, [[
+                    'id' => 'pol-2',
+                    'displayName' => 'Big Assignments',
+                    'assignments' => $assignments,
+                ]]);
+            }
+
+            public function getPolicy(string $policyType, string $policyId, array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function getOrganization(array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function applyPolicy(string $policyType, string $policyId, array $payload, array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function getServicePrincipalPermissions(array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function request(string $method, string $path, array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+        };
+    });
+
+    $svc = app(InventorySyncService::class);
+    $svc->syncNow($tenant, [
+        'policy_types' => ['deviceConfiguration'],
+        'categories' => [],
+        'include_foundations' => false,
+        'include_dependencies' => true,
+    ]);
+
+    $count = InventoryLink::query()->where('tenant_id', $tenant->getKey())->count();
+    expect($count)->toBe(50);
+});
+
+it('persists unsupported reference warnings on the sync run record', function () {
+    $tenant = Tenant::factory()->create();
+
+    $this->app->bind(GraphClientInterface::class, function () {
+        return new class implements GraphClientInterface
+        {
+            public function listPolicies(string $policyType, array $options = []): GraphResponse
+            {
+                return new GraphResponse(true, [[
+                    'id' => 'pol-warn-1',
+                    'displayName' => 'Unsupported Assignment Target',
+                    'assignments' => [
+                        ['target' => ['filterId' => 'filter-only-no-group']],
+                    ],
+                ]]);
+            }
+
+            public function getPolicy(string $policyType, string $policyId, array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function getOrganization(array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function applyPolicy(string $policyType, string $policyId, array $payload, array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function getServicePrincipalPermissions(array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+
+            public function request(string $method, string $path, array $options = []): GraphResponse
+            {
+                return new GraphResponse(true);
+            }
+        };
+    });
+
+    $svc = app(InventorySyncService::class);
+    $run = $svc->syncNow($tenant, [
+        'policy_types' => ['deviceConfiguration'],
+        'categories' => [],
+        'include_foundations' => false,
+        'include_dependencies' => true,
+    ]);
+
+    $warnings = $run->error_context['warnings'] ?? null;
+    expect($warnings)->toBeArray()->toHaveCount(1);
+    expect($warnings[0]['type'] ?? null)->toBe('unsupported_reference');
+
+    expect(InventoryLink::query()->where('tenant_id', $tenant->getKey())->count())->toBe(0);
+});
+
+it('orders inbound/outbound edges by created_at desc and applies limit-only behavior', function () {
+    $tenant = Tenant::factory()->create();
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+    ]);
+
+    $svc = app(DependencyQueryService::class);
+
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => '11111111-1111-1111-1111-111111111111',
+        'relationship_type' => 'assigned_to',
+        'created_at' => now()->subMinutes(10),
+        'updated_at' => now()->subMinutes(10),
+    ]);
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => '22222222-2222-2222-2222-222222222222',
+        'relationship_type' => 'assigned_to',
+        'created_at' => now()->subMinutes(5),
+        'updated_at' => now()->subMinutes(5),
+    ]);
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => '33333333-3333-3333-3333-333333333333',
+        'relationship_type' => 'assigned_to',
+        'created_at' => now()->subMinutes(1),
+        'updated_at' => now()->subMinutes(1),
+    ]);
+
+    $outbound = $svc->getOutboundEdges($item, null, 2);
+    expect($outbound)->toHaveCount(2);
+    expect($outbound[0]->target_id)->toBe('33333333-3333-3333-3333-333333333333');
+    expect($outbound[1]->target_id)->toBe('22222222-2222-2222-2222-222222222222');
+    expect($outbound[0]->created_at->greaterThan($outbound[1]->created_at))->toBeTrue();
+
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => 'aaaaaaaa-aaaa-aaaa-aaaa-aaaaaaaaaaaa',
+        'target_type' => 'inventory_item',
+        'target_id' => $item->external_id,
+        'relationship_type' => 'depends_on',
+        'created_at' => now()->subMinutes(9),
+        'updated_at' => now()->subMinutes(9),
+    ]);
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => 'bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb',
+        'target_type' => 'inventory_item',
+        'target_id' => $item->external_id,
+        'relationship_type' => 'depends_on',
+        'created_at' => now()->subMinutes(2),
+        'updated_at' => now()->subMinutes(2),
+    ]);
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => 'cccccccc-cccc-cccc-cccc-cccccccccccc',
+        'target_type' => 'inventory_item',
+        'target_id' => $item->external_id,
+        'relationship_type' => 'depends_on',
+        'created_at' => now()->subMinutes(1),
+        'updated_at' => now()->subMinutes(1),
+    ]);
+
+    $inbound = $svc->getInboundEdges($item, null, 2);
+    expect($inbound)->toHaveCount(2);
+    expect($inbound[0]->source_id)->toBe('cccccccc-cccc-cccc-cccc-cccccccccccc');
+    expect($inbound[1]->source_id)->toBe('bbbbbbbb-bbbb-bbbb-bbbb-bbbbbbbbbbbb');
+    expect($inbound[0]->created_at->greaterThan($inbound[1]->created_at))->toBeTrue();
+});
diff --git a/tests/Feature/DependencyQueryServiceTest.php b/tests/Feature/DependencyQueryServiceTest.php
new file mode 100644
index 0000000..8869b5b
--- /dev/null
+++ b/tests/Feature/DependencyQueryServiceTest.php
@@ -0,0 +1,45 @@
+<?php
+
+use App\Models\InventoryItem;
+use App\Models\InventoryLink;
+use App\Models\Tenant;
+use App\Services\Inventory\DependencyQueryService;
+use Illuminate\Support\Str;
+
+it('returns outbound and inbound edges filtered by tenant and direction', function () {
+    $tenant = Tenant::factory()->create();
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    // Outbound edge for this item
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => (string) Str::uuid(),
+        'relationship_type' => 'assigned_to',
+    ]);
+
+    // Inbound edge pointing to this item as target
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => (string) Str::uuid(),
+        'target_type' => 'inventory_item',
+        'target_id' => $item->external_id,
+        'relationship_type' => 'depends_on',
+    ]);
+
+    $svc = app(DependencyQueryService::class);
+
+    $outbound = $svc->getOutboundEdges($item);
+    $inbound = $svc->getInboundEdges($item);
+
+    expect($outbound->count())->toBe(1);
+    expect($inbound->count())->toBe(1);
+});
diff --git a/tests/Feature/DependencyTenantIsolationTest.php b/tests/Feature/DependencyTenantIsolationTest.php
new file mode 100644
index 0000000..2515503
--- /dev/null
+++ b/tests/Feature/DependencyTenantIsolationTest.php
@@ -0,0 +1,43 @@
+<?php
+
+use App\Models\InventoryItem;
+use App\Models\InventoryLink;
+use App\Models\Tenant;
+use App\Services\Inventory\DependencyQueryService;
+use Illuminate\Support\Str;
+
+it('does not leak edges across tenants in service queries', function () {
+    $tenantA = Tenant::factory()->create();
+    $tenantB = Tenant::factory()->create();
+
+    /** @var InventoryItem $itemA */
+    $itemA = InventoryItem::factory()->create([
+        'tenant_id' => $tenantA->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    // Edge for tenant A
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenantA->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $itemA->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => (string) Str::uuid(),
+        'relationship_type' => 'assigned_to',
+    ]);
+
+    // Edge for tenant B with same source/target ids but different tenant
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenantB->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $itemA->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => (string) Str::uuid(),
+        'relationship_type' => 'assigned_to',
+    ]);
+
+    $svc = app(DependencyQueryService::class);
+    $outboundA = $svc->getOutboundEdges($itemA);
+
+    expect($outboundA->count())->toBe(1);
+});
diff --git a/tests/Feature/InventoryItemDependenciesTest.php b/tests/Feature/InventoryItemDependenciesTest.php
new file mode 100644
index 0000000..a4ecd0c
--- /dev/null
+++ b/tests/Feature/InventoryItemDependenciesTest.php
@@ -0,0 +1,188 @@
+<?php
+
+use App\Filament\Resources\InventoryItemResource;
+use App\Models\InventoryItem;
+use App\Models\InventoryLink;
+use App\Models\Tenant;
+use Illuminate\Support\Str;
+
+it('shows zero-state when no dependencies and shows missing badge when applicable', function () {
+    [$user, $tenant] = createUserWithTenant();
+    $this->actingAs($user);
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    // Zero state
+    $url = InventoryItemResource::getUrl('view', ['record' => $item], tenant: $tenant);
+    $this->get($url)->assertOk()->assertSee('No dependencies found');
+
+    // Create a missing edge and assert badge appears
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'missing',
+        'target_id' => null,
+        'relationship_type' => 'assigned_to',
+        'metadata' => [
+            'last_known_name' => 'Ghost Target',
+            'raw_ref' => ['example' => 'ref'],
+        ],
+    ]);
+
+    $this->get($url)
+        ->assertOk()
+        ->assertSee('Missing')
+        ->assertSee('Last known: Ghost Target');
+});
+
+it('direction filter limits to outbound or inbound', function () {
+    [$user, $tenant] = createUserWithTenant();
+    $this->actingAs($user);
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    // Outbound only
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => (string) Str::uuid(),
+        'relationship_type' => 'assigned_to',
+    ]);
+
+    // Inbound only
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => (string) Str::uuid(),
+        'target_type' => 'inventory_item',
+        'target_id' => $item->external_id,
+        'relationship_type' => 'depends_on',
+    ]);
+
+    $urlOutbound = InventoryItemResource::getUrl('view', ['record' => $item], tenant: $tenant).'?direction=outbound';
+    $this->get($urlOutbound)->assertOk()->assertDontSee('No dependencies found');
+
+    $urlInbound = InventoryItemResource::getUrl('view', ['record' => $item], tenant: $tenant).'?direction=inbound';
+    $this->get($urlInbound)->assertOk()->assertDontSee('No dependencies found');
+});
+
+it('relationship filter limits edges by type', function () {
+    [$user, $tenant] = createUserWithTenant();
+    $this->actingAs($user);
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    // Two outbound edges with different relationship types.
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'missing',
+        'target_id' => null,
+        'relationship_type' => 'assigned_to',
+        'metadata' => ['last_known_name' => 'Assigned Target'],
+    ]);
+
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'missing',
+        'target_id' => null,
+        'relationship_type' => 'scoped_by',
+        'metadata' => ['last_known_name' => 'Scoped Target'],
+    ]);
+
+    $url = InventoryItemResource::getUrl('view', ['record' => $item], tenant: $tenant)
+        .'?direction=outbound&relationship_type=scoped_by';
+
+    $this->get($url)
+        ->assertOk()
+        ->assertSee('Scoped Target')
+        ->assertDontSee('Assigned Target');
+});
+
+it('does not show edges from other tenants (tenant isolation)', function () {
+    [$user, $tenant] = createUserWithTenant();
+    $this->actingAs($user);
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    $otherTenant = Tenant::factory()->create();
+
+    // Same source_id, but different tenant_id: must not be rendered.
+    InventoryLink::factory()->create([
+        'tenant_id' => $otherTenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'missing',
+        'target_id' => null,
+        'relationship_type' => 'assigned_to',
+        'metadata' => ['last_known_name' => 'Other Tenant Edge'],
+    ]);
+
+    $url = InventoryItemResource::getUrl('view', ['record' => $item], tenant: $tenant);
+    $this->get($url)
+        ->assertOk()
+        ->assertDontSee('Other Tenant Edge');
+});
+
+it('shows masked identifier when last known name is missing', function () {
+    [$user, $tenant] = createUserWithTenant();
+    $this->actingAs($user);
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => $item->external_id,
+        'target_type' => 'foundation_object',
+        'target_id' => '12345678-1234-1234-1234-123456789012',
+        'relationship_type' => 'assigned_to',
+        'metadata' => [
+            'last_known_name' => null,
+        ],
+    ]);
+
+    $url = InventoryItemResource::getUrl('view', ['record' => $item], tenant: $tenant);
+    $this->get($url)
+        ->assertOk()
+        ->assertSee('ID: 123456…');
+});
+
+it('blocks guest access to inventory item dependencies view', function () {
+    $tenant = Tenant::factory()->create();
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    $url = InventoryItemResource::getUrl('view', ['record' => $item], tenant: $tenant);
+    $this->get($url)->assertRedirect();
+});
diff --git a/tests/Unit/DependencyExtractionServiceTest.php b/tests/Unit/DependencyExtractionServiceTest.php
new file mode 100644
index 0000000..f0f83de
--- /dev/null
+++ b/tests/Unit/DependencyExtractionServiceTest.php
@@ -0,0 +1,82 @@
+<?php
+
+use App\Models\InventoryItem;
+use App\Models\InventoryLink;
+use App\Models\Tenant;
+use App\Services\Inventory\DependencyExtractionService;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Facades\Log;
+use Illuminate\Support\Str;
+
+uses(RefreshDatabase::class);
+
+it('extracts deterministically and enforces unique key', function () {
+    $tenant = Tenant::factory()->create();
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    $policyData = [
+        'id' => $item->external_id,
+        'assignments' => [
+            ['target' => ['groupId' => 'group-1']],
+            ['target' => ['groupId' => 'group-2']],
+        ],
+        'roleScopeTagIds' => ['scope-tag-1', 'scope-tag-2'],
+    ];
+
+    $svc = app(DependencyExtractionService::class);
+
+    $warnings1 = $svc->extractForPolicyData($item, $policyData);
+    $warnings2 = $svc->extractForPolicyData($item, $policyData); // re-run, should be idempotent
+
+    expect($warnings1)->toBeArray()->toBeEmpty();
+    expect($warnings2)->toBeArray()->toBeEmpty();
+
+    $edges = InventoryLink::query()->where('tenant_id', $tenant->getKey())->get();
+    expect($edges)->toHaveCount(4);
+
+    // Ensure uniqueness by tuple (source, target, type)
+    $tuples = $edges->map(fn ($e) => implode('|', [
+        $e->source_type, $e->source_id, $e->target_type, (string) $e->target_id, $e->relationship_type,
+    ]))->unique();
+
+    expect($tuples->count())->toBe(4);
+});
+
+it('handles unsupported references by recording warnings (no edges)', function () {
+    $tenant = Tenant::factory()->create();
+
+    /** @var InventoryItem $item */
+    $item = InventoryItem::factory()->create([
+        'tenant_id' => $tenant->getKey(),
+        'external_id' => (string) Str::uuid(),
+    ]);
+
+    $policyData = [
+        'id' => $item->external_id,
+        'assignments' => [
+            ['target' => ['filterId' => 'filter-only-no-group']], // no groupId shape → missing
+        ],
+    ];
+
+    Log::spy();
+
+    $svc = app(DependencyExtractionService::class);
+
+    $warnings = $svc->extractForPolicyData($item, $policyData);
+    expect($warnings)->toBeArray()->toHaveCount(1);
+    expect($warnings[0]['type'] ?? null)->toBe('unsupported_reference');
+    expect($warnings[0]['policy_id'] ?? null)->toBe($item->external_id);
+
+    expect(InventoryLink::query()->count())->toBe(0);
+
+    Log::shouldHaveReceived('info')
+        ->withArgs(fn (string $message, array $context) => $message === 'Unsupported reference shape encountered'
+            && ($context['type'] ?? null) === 'unsupported_reference'
+            && ($context['policy_id'] ?? null) === $item->external_id)
+        ->once();
+});
diff --git a/tests/Unit/InventoryLinkTest.php b/tests/Unit/InventoryLinkTest.php
new file mode 100644
index 0000000..b35a8d1
--- /dev/null
+++ b/tests/Unit/InventoryLinkTest.php
@@ -0,0 +1,52 @@
+<?php
+
+use App\Models\InventoryLink;
+use App\Models\Tenant;
+use Illuminate\Database\QueryException;
+use Illuminate\Foundation\Testing\RefreshDatabase;
+use Illuminate\Support\Str;
+
+uses(RefreshDatabase::class);
+
+it('enforces unique constraint on inventory_links', function () {
+    $tenant = Tenant::factory()->create();
+
+    $data = [
+        'tenant_id' => $tenant->getKey(),
+        'source_type' => 'inventory_item',
+        'source_id' => (string) Str::uuid(),
+        'target_type' => 'foundation_object',
+        'target_id' => (string) Str::uuid(),
+        'relationship_type' => 'assigned_to',
+        'metadata' => ['last_known_name' => 'X'],
+    ];
+
+    InventoryLink::query()->create($data);
+
+    expect(function () use ($data) {
+        InventoryLink::query()->create($data);
+    })->toThrow(QueryException::class);
+});
+
+it('scopes edges by tenant at query level', function () {
+    $tenantA = Tenant::factory()->create();
+    $tenantB = Tenant::factory()->create();
+
+    $sourceId = (string) Str::uuid();
+
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenantA->getKey(),
+        'source_id' => $sourceId,
+    ]);
+
+    InventoryLink::factory()->create([
+        'tenant_id' => $tenantB->getKey(),
+        'source_id' => $sourceId,
+    ]);
+
+    $edgesA = InventoryLink::query()->where('tenant_id', $tenantA->getKey())->get();
+    $edgesB = InventoryLink::query()->where('tenant_id', $tenantB->getKey())->get();
+
+    expect($edgesA->count())->toBe(1);
+    expect($edgesB->count())->toBe(1);
+});