optimize retrieval

public/assets/js/base.js

@@ -62,7 +62,7 @@ document.addEventListener('DOMContentLoaded', () => {
 
     function hasMeaningfulChildContent(element) {
         return element.querySelector(
-            'img, table, pre, code, ul, ol, h1, h2, h3, h4, h5, h6, a, hr'
+            'img, table, pre, code, ul, ol, h1, h2, h3, h4, h5, h6, a, hr, .badge'
         ) !== null;
     }
 
@@ -86,68 +86,23 @@ document.addEventListener('DOMContentLoaded', () => {
         });
     }
 
-    function stripAllThinkContent(container) {
+    function removeThinkSpansOnly(container) {
-        const blockSelector = 'p, div, li, blockquote';
+        container.querySelectorAll('.think').forEach((span) => {
-        const thinkSpans = Array.from(container.querySelectorAll('.think'));
+            span.remove();
-
-        if (thinkSpans.length === 0) {
-            return;
-        }
-
-        const handledBlocks = new Set();
-
-        thinkSpans.forEach((span) => {
-            const block = span.closest(blockSelector) || span.parentElement;
-
-            if (!block || handledBlocks.has(block)) {
-                return;
-            }
-
-            handledBlocks.add(block);
-
-            const thinksInBlock = Array.from(block.querySelectorAll('.think'));
-            const lastThinkInBlock = thinksInBlock[thinksInBlock.length - 1];
-
-            if (!lastThinkInBlock) {
-                return;
-            }
-
-            let node = block.firstChild;
-
-            while (node) {
-                const next = node.nextSibling;
-                const isLastThink = node === lastThinkInBlock;
-
-                node.remove();
-
-                if (isLastThink) {
-                    break;
-                }
-
-                node = next;
-            }
-
-            while (
-                block.firstChild &&
-                (
-                    (block.firstChild.nodeType === Node.TEXT_NODE &&
-                        block.firstChild.textContent.trim() === '') ||
-                    (block.firstChild.nodeType === Node.ELEMENT_NODE &&
-                        block.firstChild.tagName === 'BR')
-                )
-                ) {
-                block.firstChild.remove();
-            }
         });
 
         cleanupEmptyBlocks(container);
     }
 
-    function hasNonThinkContent(container) {
+    function cloneWithoutThinkContent(container) {
         const clone = container.cloneNode(true);
-
+        clone.querySelectorAll('.think').forEach((span) => span.remove());
-        stripAllThinkContent(clone);
         cleanupEmptyBlocks(clone);
+        return clone;
+    }
+
+    function hasNonThinkContent(container) {
+        const clone = cloneWithoutThinkContent(container);
 
         if ((clone.textContent || '').trim() !== '') {
             return true;
@@ -156,6 +111,49 @@ document.addEventListener('DOMContentLoaded', () => {
         return hasMeaningfulChildContent(clone);
     }
 
+    function keepOnlyLastThink(container) {
+        const thinkSpans = Array.from(container.querySelectorAll('.think'));
+
+        if (thinkSpans.length <= 1) {
+            cleanupEmptyBlocks(container);
+            return;
+        }
+
+        const lastThink = thinkSpans[thinkSpans.length - 1];
+
+        thinkSpans.slice(0, -1).forEach((span) => {
+            span.remove();
+        });
+
+        const blockSelector = 'p, div, li, blockquote';
+        const lastBlock = lastThink.closest(blockSelector) || lastThink.parentElement;
+
+        if (lastBlock && lastThink.parentElement === lastBlock) {
+            Array.from(lastBlock.childNodes).forEach((node) => {
+                if (node === lastThink) {
+                    return;
+                }
+
+                if (
+                    node.nodeType === Node.TEXT_NODE &&
+                    node.textContent.trim() === ''
+                ) {
+                    node.remove();
+                    return;
+                }
+
+                if (
+                    node.nodeType === Node.ELEMENT_NODE &&
+                    node.tagName === 'BR'
+                ) {
+                    node.remove();
+                }
+            });
+        }
+
+        cleanupEmptyBlocks(container);
+    }
+
     function cleanupThinkSpans(container) {
         if (!container) {
             return;
@@ -168,54 +166,11 @@ document.addEventListener('DOMContentLoaded', () => {
         }
 
         if (hasNonThinkContent(container)) {
-            stripAllThinkContent(container);
+            removeThinkSpansOnly(container);
             return;
         }
 
-        if (thinkSpans.length <= 1) {
+        keepOnlyLastThink(container);
-            return;
-        }
-
-        const blockSelector = 'p, div, li, blockquote';
-        const lastThink = thinkSpans[thinkSpans.length - 1];
-        const lastBlock = lastThink.closest(blockSelector) || lastThink.parentElement;
-
-        thinkSpans.slice(0, -1).forEach((span) => {
-            const block = span.closest(blockSelector) || span.parentElement;
-
-            if (block && block !== lastBlock) {
-                block.remove();
-                return;
-            }
-
-            if (block === lastBlock) {
-                span.remove();
-            }
-        });
-
-        if (lastBlock && lastBlock.contains(lastThink)) {
-            let node = lastBlock.firstChild;
-
-            while (node && node !== lastThink) {
-                const next = node.nextSibling;
-                node.remove();
-                node = next;
-            }
-
-            while (
-                lastThink.nextSibling &&
-                (
-                    (lastThink.nextSibling.nodeType === Node.TEXT_NODE &&
-                        lastThink.nextSibling.textContent.trim() === '') ||
-                    (lastThink.nextSibling.nodeType === Node.ELEMENT_NODE &&
-                        lastThink.nextSibling.tagName === 'BR')
-                )
-                ) {
-                lastThink.nextSibling.remove();
-            }
-        }
-
-        cleanupEmptyBlocks(container);
     }
 
     function renderBubbleContent(bubble, raw) {

src/Agent/AgentRunner.php

@@ -4,6 +4,9 @@ declare(strict_types=1);
 
 namespace App\Agent;
 
+use App\Commerce\CommerceReferenceResolver;
+use App\Commerce\CommerceReferenceStore;
+use App\Commerce\Dto\CommerceReferenceContext;
 use App\Commerce\SearchRepairService;
 use App\Commerce\ShopSearchService;
 use App\Config\AgentRunnerConfig;
@@ -30,6 +33,8 @@ final readonly class AgentRunner
         private RetrieverInterface $retriever,
         private ShopSearchService $shopSearchService,
         private SearchRepairService $searchRepairService,
+        private CommerceReferenceStore $commerceReferenceStore,
+        private CommerceReferenceResolver $commerceReferenceResolver,
         private CommerceIntentLite $commerceIntentLite,
         private OllamaClient $ollamaClient,
         private LoggerInterface $agentLogger,
@@ -52,7 +57,8 @@ final readonly class AgentRunner
 
         $shopResults = [];
         $primaryShopResults = [];
-        $sources = [];
+        $factSources = [];
+        $contextSignals = [];
         $optimizedShopQuery = '';
         $shopSearchQuery = '';
         $commerceIntent = CommerceIntentLite::NONE;
@@ -60,6 +66,8 @@ final readonly class AgentRunner
         $attemptedShopRepair = false;
         $usedShopRepair = false;
         $shopRepairQueries = [];
+        $activeCommerceReference = null;
+        $shopChecked = false;
 
         $this->agentLogger->info('Agent run started', [
             'userId' => $userId,
@@ -72,19 +80,18 @@ final readonly class AgentRunner
             }
 
             yield $this->systemMsg('Ich analysiere deine Anfrage...', 'think');
-
             yield $this->systemMsg('Ich prüfe auf Internetquellen...', 'think');
 
             $urlContent = $this->urlAnalyzer->extractContentFromPrompt($prompt);
             if ($urlContent !== '') {
-                $this->addSource($sources, 'Externe URL');
+                $this->addBadge($factSources, 'Externe URL');
             }
 
             yield $this->systemMsg('Ich hole relevante Daten aus meinem RAG-Wissen...', 'think');
 
             $knowledgeChunks = $this->retriever->retrieve($prompt);
             if ($knowledgeChunks !== []) {
-                $this->addSource($sources, 'RAG Wissen');
+                $this->addBadge($factSources, 'RAG Wissen');
             }
 
             $commerceIntent = $this->detectCommerceIntent($prompt);
@@ -93,18 +100,53 @@ final readonly class AgentRunner
                 yield $this->systemMsg('Ich optimiere die Recherche...', 'think');
 
                 $commerceHistoryContext = $this->buildCommerceHistoryContext($userId);
+                $activeCommerceReference = $this->loadCommerceReference($userId);
 
                 if ($commerceHistoryContext !== '') {
-                    $this->addSource($sources, 'Chatverlauf');
+                    $this->addBadge($contextSignals, 'Gesprächskontext');
                 }
 
-                $optimizedShopQuery = $this->buildOptimizedShopQuery(
+                if ($activeCommerceReference !== null) {
+                    $this->addBadge($contextSignals, 'Commerce-Referenz');
+                }
+
+                $isReferenceOnlyFollowUp = $this->isReferenceOnlyCommerceFollowUp(
                     $prompt,
-                    $userId,
+                    $activeCommerceReference
-                    $commerceHistoryContext
                 );
 
-                $shopSearchQuery = $optimizedShopQuery !== '' ? $optimizedShopQuery : $prompt;
+                if ($isReferenceOnlyFollowUp) {
+                    $shopSearchQuery = $this->buildDeterministicReferenceShopQuery($activeCommerceReference);
+
+                    if ($shopSearchQuery !== '') {
+                        $this->addBadge($contextSignals, 'Deterministische Referenzsuche');
+                    }
+
+                    $this->agentLogger->info('Using deterministic reference shop query', [
+                        'userId' => $userId,
+                        'commerceIntent' => $commerceIntent,
+                        'prompt' => $prompt,
+                        'shopSearchQuery' => $shopSearchQuery,
+                        'referenceProductName' => $activeCommerceReference?->productName,
+                        'referenceFocusTerms' => $activeCommerceReference?->focusTerms,
+                    ]);
+                } else {
+                    $optimizedShopQuery = $this->buildOptimizedShopQuery(
+                        $prompt,
+                        $userId,
+                        $commerceHistoryContext
+                    );
+
+                    if ($optimizedShopQuery !== '' && $optimizedShopQuery !== $prompt) {
+                        $this->addBadge($contextSignals, 'Query-Optimierung');
+                    }
+
+                    $shopSearchQuery = $optimizedShopQuery !== '' ? $optimizedShopQuery : $prompt;
+                }
+
+                if ($shopSearchQuery === '') {
+                    $shopSearchQuery = $prompt;
+                }
 
                 $this->agentLogger->info('Commerce search prepared', [
                     'userId' => $userId,
@@ -112,8 +154,11 @@ final readonly class AgentRunner
                     'usedOptimizedShopQuery' => $optimizedShopQuery !== '',
                     'optimizedShopQuery' => $optimizedShopQuery,
                     'shopSearchQuery' => $shopSearchQuery,
+                    'usedDeterministicReferenceQuery' => $isReferenceOnlyFollowUp,
                     'hasCommerceHistoryContext' => $commerceHistoryContext !== '',
                     'commerceHistoryContextLength' => mb_strlen($commerceHistoryContext),
+                    'hasActiveCommerceReference' => $activeCommerceReference !== null,
+                    'activeCommerceReferenceProduct' => $activeCommerceReference?->productName,
                 ]);
 
                 yield $this->systemMsg(
@@ -121,11 +166,14 @@ final readonly class AgentRunner
                     'think'
                 );
 
+                $shopChecked = true;
+
                 $primaryShopResults = $this->searchShop(
                     $shopSearchQuery,
                     $commerceIntent,
                     $userId,
-                    $commerceHistoryContext
+                    $commerceHistoryContext,
+                    $activeCommerceReference
                 );
 
                 $repairPayload = $this->repairShopResults(
@@ -144,11 +192,13 @@ final readonly class AgentRunner
                 $shopRepairQueries = $repairPayload['repairQueries'];
 
                 if ($shopResults !== []) {
-                    $this->addSource($sources, 'Shopsystem');
+                    $this->addBadge($factSources, 'Shopsystem');
+                } elseif ($shopChecked) {
+                    $this->addBadge($factSources, 'Shopsystem geprüft');
                 }
 
                 if ($attemptedShopRepair) {
-                    $this->addSource($sources, 'Erweiterte Shopsuche');
+                    $this->addBadge($contextSignals, 'Erweiterte Shopsuche');
                 }
             }
 
@@ -176,6 +226,7 @@ final readonly class AgentRunner
                     'shopSearchQuery' => $shopSearchQuery,
                     'primaryShopResultsCount' => count($primaryShopResults),
                     'shopResultsCount' => count($shopResults),
+                    'shopChecked' => $shopChecked,
                     'attemptedShopRepair' => $attemptedShopRepair,
                     'usedShopRepair' => $usedShopRepair,
                     'shopRepairQueries' => $shopRepairQueries,
@@ -192,14 +243,22 @@ final readonly class AgentRunner
                 ]);
             }
 
-            if ($sources !== []) {
+            if ($factSources !== [] || $contextSignals !== []) {
-                yield $this->emitSources($sources, 'Genutzte Quellen: ');
+                yield $this->emitSourceSummary(
+                    $factSources,
+                    $contextSignals,
+                    'Genutzte Datenpfade'
+                );
             }
 
             $fullOutput = yield from $this->streamFinalAnswer($finalPrompt);
 
-            if ($sources !== []) {
+            if ($factSources !== [] || $contextSignals !== []) {
-                yield $this->emitSources($sources, 'Quellen: ');
+                yield $this->emitSourceSummary(
+                    $factSources,
+                    $contextSignals,
+                    'Quellen und Signale'
+                );
             }
 
             if ($this->debug) {
@@ -207,10 +266,11 @@ final readonly class AgentRunner
             }
 
             if ($fullOutput !== '') {
-                $this->contextService->appendHistory(
+                $this->persistConversationState(
-                    $userId,
+                    userId: $userId,
-                    $prompt,
+                    prompt: $prompt,
-                    $fullOutput
+                    fullOutput: $fullOutput,
+                    shopResults: $shopResults
                 );
             }
 
@@ -221,6 +281,7 @@ final readonly class AgentRunner
                 'commerceIntent' => $commerceIntent,
                 'primaryShopResultsCount' => count($primaryShopResults),
                 'shopResultsCount' => count($shopResults),
+                'shopChecked' => $shopChecked,
                 'attemptedShopRepair' => $attemptedShopRepair,
                 'usedShopRepair' => $usedShopRepair,
                 'shopRepairQueries' => $shopRepairQueries,
@@ -231,6 +292,8 @@ final readonly class AgentRunner
                 'shopSearchQuery' => $shopSearchQuery,
                 'hasCommerceHistoryContext' => $commerceHistoryContext !== '',
                 'commerceHistoryContextLength' => mb_strlen($commerceHistoryContext),
+                'hasActiveCommerceReference' => $activeCommerceReference !== null,
+                'activeCommerceReferenceProduct' => $activeCommerceReference?->productName,
             ]);
         } catch (Throwable $e) {
             $this->agentLogger->error('Agent run failed', [
@@ -298,6 +361,42 @@ final readonly class AgentRunner
         return $this->sanitizeOptimizedShopQuery($optimizedQuery);
     }
 
+    private function isReferenceOnlyCommerceFollowUp(
+        string $prompt,
+        ?CommerceReferenceContext $referenceContext
+    ): bool {
+        if ($referenceContext === null) {
+            return false;
+        }
+
+        $normalizedPrompt = mb_strtolower(trim($prompt), 'UTF-8');
+        $normalizedPrompt = preg_replace('/[^\p{L}\p{N}\s]+/u', ' ', $normalizedPrompt) ?? $normalizedPrompt;
+        $normalizedPrompt = preg_replace('/\s+/u', ' ', $normalizedPrompt) ?? $normalizedPrompt;
+        $normalizedPrompt = trim($normalizedPrompt);
+
+        if ($normalizedPrompt === '') {
+            return false;
+        }
+
+        if (preg_match('/\b(testomat|lab|evo|eco|calc|thcl|808|2000)\b/u', $normalizedPrompt) === 1) {
+            return false;
+        }
+
+        return preg_match(
+                '/\b(preis|preise|kosten|kostet|dazu|dafuer|dafür|davon|was kostet das|verfuegbarkeit|verfügbarkeit|shop|link)\b/u',
+                $normalizedPrompt
+            ) === 1;
+    }
+
+    private function buildDeterministicReferenceShopQuery(?CommerceReferenceContext $referenceContext): string
+    {
+        if ($referenceContext === null) {
+            return '';
+        }
+
+        return trim($referenceContext->buildReferenceSearchText());
+    }
+
     /**
      * @return array{
      *     results: array,
@@ -346,13 +445,15 @@ final readonly class AgentRunner
         string $query,
         string $commerceIntent,
         string $userId,
-        string $commerceHistoryContext = ''
+        string $commerceHistoryContext = '',
+        ?CommerceReferenceContext $referenceContext = null
     ): array {
         try {
             return $this->shopSearchService->search(
                 $query,
                 $commerceIntent,
-                $commerceHistoryContext
+                $commerceHistoryContext,
+                $referenceContext
             );
         } catch (Throwable $e) {
             $this->agentLogger->warning('Shop search failed, continuing without shop results', [
@@ -361,6 +462,8 @@ final readonly class AgentRunner
                 'query' => $query,
                 'hasCommerceHistoryContext' => $commerceHistoryContext !== '',
                 'commerceHistoryContextLength' => mb_strlen($commerceHistoryContext),
+                'hasReferenceContext' => $referenceContext !== null,
+                'referenceProductName' => $referenceContext?->productName,
                 'exception' => $e,
             ]);
 
@@ -376,6 +479,64 @@ final readonly class AgentRunner
         );
     }
 
+    private function loadCommerceReference(string $userId): ?CommerceReferenceContext
+    {
+        try {
+            return $this->commerceReferenceStore->load($userId);
+        } catch (Throwable $e) {
+            $this->agentLogger->warning('Failed to load commerce reference context', [
+                'userId' => $userId,
+                'exception' => $e,
+            ]);
+
+            return null;
+        }
+    }
+
+    /**
+     * @param array<int, mixed> $shopResults
+     */
+    private function storeCommerceReference(string $userId, string $prompt, string $answer, array $shopResults): void
+    {
+        try {
+            $referenceContext = $this->commerceReferenceResolver->resolveFromCommerceTurn(
+                $prompt,
+                $answer,
+                $shopResults
+            );
+
+            if ($referenceContext === null) {
+                return;
+            }
+
+            $this->commerceReferenceStore->save($userId, $referenceContext);
+        } catch (Throwable $e) {
+            $this->agentLogger->warning('Failed to persist commerce reference context', [
+                'userId' => $userId,
+                'exception' => $e,
+            ]);
+        }
+    }
+
+    /**
+     * @param array<int, mixed> $shopResults
+     */
+    private function persistConversationState(
+        string $userId,
+        string $prompt,
+        string $fullOutput,
+        array $shopResults
+    ): void {
+        $this->contextService->appendHistory($userId, $prompt, $fullOutput);
+
+        $this->storeCommerceReference(
+            userId: $userId,
+            prompt: $prompt,
+            answer: $fullOutput,
+            shopResults: $shopResults
+        );
+    }
+
     private function limitKnowledgeChunks(array $knowledgeChunks, string $commerceIntent): array
     {
         return match ($commerceIntent) {
@@ -447,22 +608,36 @@ final readonly class AgentRunner
     }
 
     /**
-     * @param string[] $sources
+     * @param string[] $factSources
+     * @param string[] $contextSignals
      */
-    private function emitSources(array $sources, string $prefix): string
+    private function emitSourceSummary(array $factSources, array $contextSignals, string $label): string
     {
-        return $this->systemMsg($prefix . implode(' ', $sources), 'info');
+        $parts = [];
+
+        if ($factSources !== []) {
+            $parts[] = 'Fakten: ' . implode(' ', $factSources);
+        }
+
+        if ($contextSignals !== []) {
+            $parts[] = 'Kontext: ' . implode(' ', $contextSignals);
+        }
+
+        return $this->systemMsg(
+            $label . ': ' . implode(' &nbsp;&nbsp; ', $parts),
+            'info'
+        );
     }
 
     /**
-     * @param string[] $sources
+     * @param string[] $target
      */
-    private function addSource(array &$sources, string $label): void
+    private function addBadge(array &$target, string $label): void
     {
         $badge = $this->badge($label);
 
-        if (!in_array($badge, $sources, true)) {
+        if (!in_array($badge, $target, true)) {
-            $sources[] = $badge;
+            $target[] = $badge;
         }
     }
 

src/Agent/PromptBuilder.php

@@ -14,7 +14,6 @@ use RuntimeException;
 
 final readonly class PromptBuilder
 {
-
     public function __construct(
         private ContextService $contextService,
         private SystemPromptRepository $systemPromptRepository,
@@ -49,12 +48,24 @@ final readonly class PromptBuilder
 
         $hasShopResults = $shopResults !== [];
         $isTechnicalProductQuestion = $this->isLikelyTechnicalProductQuestion($prompt);
+        $isPriceDrivenQuestion = $this->isLikelyPriceDrivenQuestion($prompt);
 
         $systemBlock = $this->buildSystemBlock();
         $shopBlock = $this->buildShopBlock($shopResults, $swagFullOutPut);
-        $outputPriorityBlock = $this->buildOutputPriorityBlock($hasShopResults);
+        $outputPriorityBlock = $this->buildOutputPriorityBlock($hasShopResults, $isPriceDrivenQuestion);
-        $responseFormatBlock = $this->buildResponseFormatBlock($prompt, $hasShopResults, $isTechnicalProductQuestion);
+        $responseFormatBlock = $this->buildResponseFormatBlock(
-        $knowledgeBlock = $this->buildKnowledgeBlock($knowledgeChunks, $urlContent, $prompt, $hasShopResults);
+            $prompt,
+            $hasShopResults,
+            $isTechnicalProductQuestion,
+            $isPriceDrivenQuestion
+        );
+        $knowledgeBlock = $this->buildKnowledgeBlock(
+            $knowledgeChunks,
+            $urlContent,
+            $prompt,
+            $hasShopResults,
+            $isPriceDrivenQuestion
+        );
         $userBlock = $this->buildUserBlock($prompt);
 
         $fixedPrompt = $this->implodeBlocks([
@@ -231,7 +242,9 @@ final readonly class PromptBuilder
                 "Output real URL values exactly as provided in the shop results. Do not replace them with placeholders, link labels, or product names.\n" .
                 "Do not infer undocumented technical specifications from shop data.\n" .
                 "Commercial fields from shop data may only be assigned to a product if the shop item clearly matches the same product identity.\n" .
-                "Do not merge a device identified in retrieved knowledge with price, URL, product number, or availability from a different shop item such as a reagent, accessory, kit, consumable, or service item.";
+                "Do not merge a device identified in retrieved knowledge with price, URL, product number, or availability from a different shop item such as a reagent, accessory, kit, consumable, or service item.\n" .
+                "If shop results only contain accessories, reagents, indicators, or consumables, do not conclude that no matching main device exists unless the sources explicitly support that conclusion.\n" .
+                "If the user asks for price filtering, use the numeric prices in these live shop results as the decisive source for filtering.";
 
             if ($totalCount > count($limitedShopResults)) {
                 $header .= "\n" .
@@ -247,12 +260,20 @@ final readonly class PromptBuilder
     /**
      * Build a small priority block that tells the model what to surface first.
      */
-    private function buildOutputPriorityBlock(bool $hasShopResults): string
+    private function buildOutputPriorityBlock(bool $hasShopResults, bool $isPriceDrivenQuestion): string
     {
         if (!$hasShopResults) {
             return '';
         }
 
+        if ($isPriceDrivenQuestion) {
+            return
+                "OUTPUT PRIORITY:\n" .
+                "For price-driven questions, evaluate shop results first for numeric price filtering.\n" .
+                "Use retrieved knowledge afterwards only to add technical context or explain missing commercial coverage.\n" .
+                "Do not let accessory-only shop results prove that no matching device exists unless the sources explicitly support that conclusion.\n";
+        }
+
         return
             "OUTPUT PRIORITY:\n" .
             "Use retrieved knowledge first to determine the technically matching product or answer.\n" .
@@ -263,7 +284,8 @@ final readonly class PromptBuilder
     private function buildResponseFormatBlock(
         string $prompt,
         bool $hasShopResults,
-        bool $isTechnicalProductQuestion
+        bool $isTechnicalProductQuestion,
+        bool $isPriceDrivenQuestion
     ): string {
         $rules = [
             "RESPONSE FORMAT RULES:",
@@ -284,6 +306,8 @@ final readonly class PromptBuilder
             $rules[] = "- Only use shop price, URL, product number, or availability for the main product when the shop result clearly matches that same main product.";
             $rules[] = "- If the matching shop item appears to be an accessory, reagent, consumable, set, or kit, keep it separate and do not present its commercial fields as the main device.";
             $rules[] = "- If the commercial match is uncertain, say that commercial details for the main product are not clearly available in the provided shop results.";
+            $rules[] = "- If the question includes a price threshold, filter using only explicit numeric shop prices.";
+            $rules[] = "- Do not say that no device exists above a threshold merely because only cheaper accessories were found in the shop results.";
         } else {
             $rules[] = "- If no shop results are present, do not compensate by inventing external products or external manufacturers.";
         }
@@ -294,6 +318,12 @@ final readonly class PromptBuilder
             $rules[] = "- If the sources only support a negative finding, output only that negative finding and do not add speculative alternatives.";
         }
 
+        if ($isPriceDrivenQuestion) {
+            $rules[] = "- For price-driven questions, answer the threshold result first.";
+            $rules[] = "- If no grounded shop product fulfills the threshold, say that clearly.";
+            $rules[] = "- Then optionally explain whether retrieved knowledge mentions relevant devices that are not commercially listed in the current shop results.";
+        }
+
         if ($this->asksForAccessoryOrBundle($prompt)) {
             $rules[] = "- If the user asks for a matching accessory, separate the answer into: main device and matching accessory.";
             $rules[] = "- The main device must come first. The accessory must not replace the main device.";
@@ -304,14 +334,13 @@ final readonly class PromptBuilder
         return implode("\n", $rules);
     }
 
-    /**
+    private function buildKnowledgeBlock(
-     * Build the knowledge block.
+        array $knowledgeChunks,
-     *
+        string $urlContent,
-     * Retrieved knowledge remains the main source for technical matching and explanation.
+        string $prompt,
-     * Shop data is preferred for current commercial fields.
+        bool $hasShopResults,
-     */
+        bool $isPriceDrivenQuestion
-    private function buildKnowledgeBlock(array $knowledgeChunks, string $urlContent, string $prompt, bool $hasShopResults): string
+    ): string {
-    {
         $knowledgeParts = [];
         $isTechnicalProductQuestion = $this->isLikelyTechnicalProductQuestion($prompt);
 
@@ -334,7 +363,7 @@ final readonly class PromptBuilder
                     "LANGUAGE RULES:\n" .
                     implode("\n", $this->buildLanguageRules()),
                     "FACT GROUNDING RULES:\n" .
-                    implode("\n", $this->buildFactGroundingRules($isTechnicalProductQuestion, $hasShopResults)),
+                    implode("\n", $this->buildFactGroundingRules($isTechnicalProductQuestion, $hasShopResults, $isPriceDrivenQuestion)),
                     "RETRIEVED KNOWLEDGE (primary for technical matching and factual explanation):\n" .
                     "Source: Documents\n" .
                     implode("\n\n", $lines),
@@ -354,13 +383,6 @@ final readonly class PromptBuilder
         return $this->implodeBlocks($knowledgeParts);
     }
 
-    /**
-     * Resolve how many characters may still be used by history.
-     *
-     * The active model num_ctx is converted into a conservative prompt budget.
-     * Shop, knowledge and user question are fixed priority blocks.
-     * History only receives the remaining space.
-     */
     private function resolveHistoryBudgetChars(string $fixedPrompt): int
     {
         $numCtx = $this->modelGenerationConfigProvider->getActiveNumCtx();
@@ -407,8 +429,11 @@ final readonly class PromptBuilder
     /**
      * @return string[]
      */
-    private function buildFactGroundingRules(bool $isTechnicalProductQuestion, bool $hasShopResults): array
+    private function buildFactGroundingRules(
-    {
+        bool $isTechnicalProductQuestion,
+        bool $hasShopResults,
+        bool $isPriceDrivenQuestion
+    ): array {
         $rules = [
             "- State only facts that are explicitly present in the provided sources.",
             "- Extract concrete values exactly when they are present, including units, ranges, model names, indicator names, IP classes, temperatures, pressures, dimensions, counts, relay outputs, current outputs, and error codes.",
@@ -437,6 +462,11 @@ final readonly class PromptBuilder
                 "- Only use commercial fields for the main product when the shop item and the technically identified product clearly refer to the same product identity.",
                 "- If the shop match is ambiguous, keep the technical identification and commercial details separate.",
             ]);
+
+            if ($isPriceDrivenQuestion) {
+                $rules[] = "- For price-threshold questions, shop prices are authoritative for the threshold check.";
+                $rules[] = "- Accessory-only shop hits do not prove that no qualifying device exists.";
+            }
         } else {
             $rules[] = "- Use retrieved knowledge as authoritative for factual answers.";
             $rules[] = "- If no shop results are present, do not compensate with external recommendations or external product suggestions.";
@@ -523,6 +553,20 @@ final readonly class PromptBuilder
         return preg_match('/\b[\p{L}]{2,}\s?\d{2,5}\b/u', $prompt) === 1;
     }
 
+    private function isLikelyPriceDrivenQuestion(string $prompt): bool
+    {
+        $normalized = mb_strtolower($prompt, 'UTF-8');
+
+        if (preg_match('/\b(mehr\s+als|über|ueber|größer\s+als|groesser\s+als|unter|bis|ab|mindestens|min)\s+\d+(?:[.,]\d+)?\s*(?:euro|eur|€)\b/u', $normalized) === 1) {
+            return true;
+        }
+
+        return str_contains($normalized, 'preis')
+            || str_contains($normalized, 'preise')
+            || str_contains($normalized, 'kosten')
+            || str_contains($normalized, 'kostet');
+    }
+
     private function asksForAccessoryOrBundle(string $prompt): bool
     {
         $normalized = mb_strtolower($prompt, 'UTF-8');

src/Commerce/CommerceQueryParser.php

@@ -4,6 +4,7 @@ declare(strict_types=1);
 
 namespace App\Commerce;
 
+use App\Commerce\Dto\CommerceReferenceContext;
 use App\Commerce\Dto\CommerceSearchQuery;
 use App\Config\CommerceIntentConfig;
 use App\Config\CommerceQueryParserConfig;
@@ -23,10 +24,12 @@ final readonly class CommerceQueryParser
     public function parse(
         string $originalPrompt,
         string $intent,
-        string $historyContext = ''
+        string $historyContext = '',
+        ?CommerceReferenceContext $referenceContext = null
     ): CommerceSearchQuery {
         $normalizedPrompt = $this->normalize($originalPrompt);
         $isDirectProductQuery = $this->isDirectProductQuery($normalizedPrompt);
+        $isReferenceOnlyFollowUp = $this->isReferenceOnlyFollowUp($normalizedPrompt);
 
         [$priceMin, $priceMax] = $this->extractPriceRange($normalizedPrompt);
         $sizes = $this->extractSizes($normalizedPrompt);
@@ -44,7 +47,7 @@ final readonly class CommerceQueryParser
         if (
             !$isDirectProductQuery
             && $historyContext !== ''
-            && $this->shouldUseHistoryContext($normalizedPrompt)
+            && $this->shouldUseHistoryContext($normalizedPrompt, $searchText)
         ) {
             $latestHistoryQuestion = $this->extractLatestQuestionFromHistory($historyContext);
 
@@ -73,7 +76,29 @@ final readonly class CommerceQueryParser
             }
         }
 
-        $finalSearchText = $searchText !== '' ? $searchText : $normalizedPrompt;
+        if (
+            !$isDirectProductQuery
+            && $referenceContext !== null
+            && $this->shouldUseReferenceContext($normalizedPrompt, $searchText)
+        ) {
+            $referenceSearchText = $this->buildReferenceSearchText($referenceContext);
+
+            if ($isReferenceOnlyFollowUp || $this->isTooGenericSearchText($searchText)) {
+                $searchText = $referenceSearchText !== '' ? $referenceSearchText : $searchText;
+            } else {
+                $searchText = $this->mergeSearchTexts($referenceSearchText, $searchText);
+            }
+
+            if (($brand === null || $brand === '') && $referenceContext->manufacturer !== null) {
+                $normalizedManufacturer = $this->normalize($referenceContext->manufacturer);
+
+                if ($normalizedManufacturer !== '') {
+                    $brand = $normalizedManufacturer;
+                }
+            }
+        }
+
+        $finalSearchText = trim($searchText !== '' ? $searchText : $normalizedPrompt);
 
         return new CommerceSearchQuery(
             originalPrompt: $originalPrompt,
@@ -93,7 +118,7 @@ final readonly class CommerceQueryParser
     {
         $value = $this->textNormalizer->normalize($prompt);
         $value = $this->queryCleaner->clean($value);
-        $value = mb_strtolower(trim($value));
+        $value = mb_strtolower(trim($value), 'UTF-8');
         $value = str_replace(['€'], ' euro ', $value);
         $value = preg_replace('/[^\p{L}\p{N}\s.,\-]/u', ' ', $value) ?? $value;
         $value = preg_replace('/\s+/u', ' ', $value) ?? $value;
@@ -126,6 +151,17 @@ final readonly class CommerceQueryParser
             $priceMin = $this->toFloat($m[1]);
         }
 
+        // NEW:
+        // Recognize comparative lower-bound phrasing such as:
+        // - mehr als 3000 euro
+        // - über 3000 euro
+        // - ueber 3000 euro
+        // - größer als 3000 euro
+        // - groesser als 3000 euro
+        if (preg_match('/\b(?:mehr\s+als|über|ueber|größer\s+als|groesser\s+als)\s+(\d+(?:[.,]\d+)?)\s+euro\b/u', $prompt, $m) === 1) {
+            $priceMin = $this->toFloat($m[1]);
+        }
+
         return [$priceMin, $priceMax];
     }
 
@@ -152,7 +188,10 @@ final readonly class CommerceQueryParser
             }
         }
 
-        return array_values(array_unique(array_filter($sizes, static fn($v) => $v !== '')));
+        return array_values(array_unique(array_filter(
+            $sizes,
+            static fn(string $value): bool => $value !== ''
+        )));
     }
 
     private function extractBrand(string $prompt): ?string
@@ -184,6 +223,7 @@ final readonly class CommerceQueryParser
 
         foreach ($this->config->getPhrasesToRemove() as $phrase) {
             $normalizedPhrase = $this->normalize((string) $phrase);
+
             if ($normalizedPhrase === '') {
                 continue;
             }
@@ -193,6 +233,7 @@ final readonly class CommerceQueryParser
 
         foreach ($sizes as $size) {
             $normalizedSize = $this->normalize((string) $size);
+
             if ($normalizedSize === '') {
                 continue;
             }
@@ -207,6 +248,7 @@ final readonly class CommerceQueryParser
         if ($priceMin !== null || $priceMax !== null) {
             $text = preg_replace('/\bzwischen\s+\d+(?:[.,]\d+)?\s+und\s+\d+(?:[.,]\d+)?\s*euro\b/u', ' ', $text) ?? $text;
             $text = preg_replace('/\b(?:unter|bis|max(?:imal)?|ab|mindestens|min)\s+\d+(?:[.,]\d+)?\s*euro\b/u', ' ', $text) ?? $text;
+            $text = preg_replace('/\b(?:mehr\s+als|über|ueber|größer\s+als|groesser\s+als)\s+\d+(?:[.,]\d+)?\s*euro\b/u', ' ', $text) ?? $text;
             $text = preg_replace('/\b' . $this->intentConfig->getPricePattern() . '\b/u', ' ', $text) ?? $text;
         }
 
@@ -219,14 +261,14 @@ final readonly class CommerceQueryParser
         );
 
         $tokens = $this->filterSearchTokens($tokens);
+        $tokens = $this->stripReferenceOnlyTokens($tokens);
 
         return trim(implode(' ', $tokens));
     }
 
     private function buildDirectProductSearchText(string $prompt): string
     {
-        $text = $prompt;
+        $text = preg_replace('/\s+/u', ' ', $prompt) ?? $prompt;
-        $text = preg_replace('/\s+/u', ' ', $text) ?? $text;
         $text = trim($text, " \t\n\r\0\x0B-.,");
 
         $tokens = array_filter(
@@ -234,17 +276,61 @@ final readonly class CommerceQueryParser
             static fn(string $token): bool => mb_strlen($token) > 0
         );
 
-        $tokens = array_values(array_unique($tokens));
+        return trim(implode(' ', array_values(array_unique($tokens))));
-
-        return trim(implode(' ', $tokens));
     }
 
-    private function shouldUseHistoryContext(string $prompt): bool
+    private function shouldUseHistoryContext(string $prompt, string $searchText): bool
     {
-        return preg_match(
+        if ($this->isReferenceOnlyFollowUp($prompt)) {
-                '/\b(' . $this->config->getHistoryContextPattern() . ')\b/u',
+            return true;
-                $prompt
+        }
-            ) === 1;
+
+        if ($this->isTooGenericSearchText($searchText)) {
+            return true;
+        }
+
+        return preg_match('/\b(' . $this->config->getHistoryContextPattern() . ')\b/u', $prompt) === 1;
+    }
+
+    private function shouldUseReferenceContext(string $prompt, string $searchText): bool
+    {
+        if ($this->isReferenceOnlyFollowUp($prompt)) {
+            return true;
+        }
+
+        return $this->isTooGenericSearchText($searchText);
+    }
+
+    private function isReferenceOnlyFollowUp(string $prompt): bool
+    {
+        return preg_match('/\b(' . $this->config->getReferenceFollowUpPattern() . ')\b/u', $prompt) === 1;
+    }
+
+    private function isTooGenericSearchText(string $searchText): bool
+    {
+        $tokens = array_values(array_filter(
+            preg_split('/\s+/u', $searchText, -1, PREG_SPLIT_NO_EMPTY) ?: [],
+            static fn(string $token): bool => $token !== ''
+        ));
+
+        if ($tokens === []) {
+            return true;
+        }
+
+        $genericTokens = array_fill_keys($this->config->getReferenceOnlyTokens(), true);
+
+        foreach ($tokens as $token) {
+            if (!isset($genericTokens[$token])) {
+                return false;
+            }
+        }
+
+        return true;
+    }
+
+    private function buildReferenceSearchText(CommerceReferenceContext $referenceContext): string
+    {
+        return $this->normalize($referenceContext->buildReferenceSearchText());
     }
 
     private function extractLatestQuestionFromHistory(string $historyContext): string
@@ -256,6 +342,7 @@ final readonly class CommerceQueryParser
         }
 
         $questions = $matches[1] ?? [];
+
         if ($questions === []) {
             return '';
         }
@@ -265,11 +352,11 @@ final readonly class CommerceQueryParser
         return is_string($lastQuestion) ? trim($lastQuestion) : '';
     }
 
-    private function mergeSearchTexts(string $historySearchText, string $currentSearchText): string
+    private function mergeSearchTexts(string $left, string $right): string
     {
         $tokens = [];
 
-        foreach ([$historySearchText, $currentSearchText] as $text) {
+        foreach ([$left, $right] as $text) {
             if ($text === '') {
                 continue;
             }
@@ -294,11 +381,25 @@ final readonly class CommerceQueryParser
      */
     private function filterSearchTokens(array $tokens): array
     {
-        $stopWords = $this->config->getFilterSearchTokensPattern();
+        $stopWords = array_fill_keys($this->config->getFilterSearchTokensPattern(), true);
 
         return array_values(array_filter(
             $tokens,
-            static fn(string $token): bool => !in_array($token, $stopWords, true)
+            static fn(string $token): bool => !isset($stopWords[$token])
+        ));
+    }
+
+    /**
+     * @param string[] $tokens
+     * @return string[]
+     */
+    private function stripReferenceOnlyTokens(array $tokens): array
+    {
+        $referenceOnly = array_fill_keys($this->config->getReferenceOnlyTokens(), true);
+
+        return array_values(array_filter(
+            $tokens,
+            static fn(string $token): bool => !isset($referenceOnly[$token])
         ));
     }
 
@@ -318,11 +419,7 @@ final readonly class CommerceQueryParser
 
         $tokens = preg_split('/\s+/u', $prompt, -1, PREG_SPLIT_NO_EMPTY) ?: [];
 
-        if (count($tokens) <= 4 && preg_match('/\d/u', $prompt) === 1) {
+        return count($tokens) <= 4 && preg_match('/\d/u', $prompt) === 1;
-            return true;
-        }
-
-        return false;
     }
 
     private function containsModelLikePhrase(string $text): bool

src/Commerce/CommerceReferenceResolver.php

@@ -0,0 +1,239 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Commerce;
+
+use App\Commerce\Dto\CommerceReferenceContext;
+
+final readonly class CommerceReferenceResolver
+{
+    /**
+     * @param array<int, array<string, mixed>> $shopResults
+     */
+    public function resolveFromCommerceTurn(
+        string $prompt,
+        string $answerText,
+        array $shopResults
+    ): ?CommerceReferenceContext {
+        $fromText = $this->resolveFromText($prompt, $answerText);
+        $fromShop = $this->resolveFromShopResults($prompt, $shopResults);
+
+        if ($fromText !== null && $fromShop !== null && $this->areCompatibleProductNames($fromText->productName, $fromShop->productName)) {
+            return new CommerceReferenceContext(
+                productName: $fromShop->productName,
+                productNumber: $fromShop->productNumber,
+                manufacturer: $fromShop->manufacturer ?? $fromText->manufacturer,
+                url: $fromShop->url,
+                sourceType: 'shop',
+                confidence: 1.0,
+                resolvedFromPrompt: $fromText->resolvedFromPrompt ?? $fromShop->resolvedFromPrompt,
+                resolvedAt: (new \DateTimeImmutable())->format(\DateTimeInterface::ATOM),
+                focusTerms: $this->mergeFocusTerms(
+                    $fromText->focusTerms,
+                    $fromShop->focusTerms
+                ),
+            );
+        }
+
+        if ($fromText !== null) {
+            return $fromText;
+        }
+
+        return $fromShop;
+    }
+
+    /**
+     * @param array<int, array<string, mixed>> $shopResults
+     */
+    private function resolveFromShopResults(string $prompt, array $shopResults): ?CommerceReferenceContext
+    {
+        $top = $shopResults[0] ?? null;
+
+        if (!is_array($top)) {
+            return null;
+        }
+
+        $name = $this->extractString($top, 'name');
+        $productNumber = $this->extractString($top, 'productNumber');
+        $manufacturer = $this->extractString($top, 'manufacturer');
+        $url = $this->extractString($top, 'url');
+
+        if ($name === '') {
+            return null;
+        }
+
+        return new CommerceReferenceContext(
+            productName: $name,
+            productNumber: $productNumber !== '' ? $productNumber : null,
+            manufacturer: $manufacturer !== '' ? $manufacturer : null,
+            url: $url !== '' ? $url : null,
+            sourceType: 'shop',
+            confidence: 1.0,
+            resolvedFromPrompt: trim($prompt) !== '' ? trim($prompt) : null,
+            resolvedAt: (new \DateTimeImmutable())->format(\DateTimeInterface::ATOM),
+            focusTerms: $this->extractFocusTerms($prompt . "\n" . $name),
+        );
+    }
+
+    private function resolveFromText(string $prompt, string $answerText): ?CommerceReferenceContext
+    {
+        $text = trim($prompt . "\n" . $answerText);
+
+        if ($text === '') {
+            return null;
+        }
+
+        $patterns = [
+            '/\b(Testomat\s+2000\s+THCL)\b/ui',
+            '/\b(Testomat\s+808)\b/ui',
+            '/\b(Testomat\s+EVO\s+TH)\b/ui',
+            '/\b(Testomat\s+EVO\s+CALC)\b/ui',
+            '/\b(Testomat\s+ECO\s+PLUS)\b/ui',
+            '/\b(Testomat\s+ECO\s+C)\b/ui',
+            '/\b(Testomat\s+ECO)\b/ui',
+            '/\b(Testomat\s+LAB\s+CL)\b/ui',
+            '/\b(Testomat\s+LAB\s+MONO)\b/ui',
+            '/\b(Testomat\s+2000)\b/ui',
+        ];
+
+        foreach ($patterns as $pattern) {
+            if (!preg_match($pattern, $text, $matches)) {
+                continue;
+            }
+
+            $productName = trim((string) ($matches[1] ?? ''));
+
+            if ($productName === '') {
+                continue;
+            }
+
+            return new CommerceReferenceContext(
+                productName: $productName,
+                productNumber: null,
+                manufacturer: null,
+                url: null,
+                sourceType: 'conversation',
+                confidence: 0.8,
+                resolvedFromPrompt: trim($prompt) !== '' ? trim($prompt) : null,
+                resolvedAt: (new \DateTimeImmutable())->format(\DateTimeInterface::ATOM),
+                focusTerms: $this->extractFocusTerms($text),
+            );
+        }
+
+        return null;
+    }
+
+    /**
+     * @return string[]
+     */
+    private function extractFocusTerms(string $text): array
+    {
+        $normalized = $this->normalizeText($text);
+
+        if ($normalized === '') {
+            return [];
+        }
+
+        $patterns = [
+            'indikator' => '/\bindikator(?:en)?\b/u',
+            'indikatoren' => '/\bindikator(?:en)?\b/u',
+            'reagenz' => '/\breagenz(?:ien)?\b/u',
+            'reagenzien' => '/\breagenz(?:ien)?\b/u',
+            'zubehör' => '/\bzubeh[oö]r\b/u',
+            'ersatzteil' => '/\bersatzteile?\b/u',
+            'ersatzteile' => '/\bersatzteile?\b/u',
+            'service-set' => '/\bservice(?:\s|-)?set\b/u',
+            'filter' => '/\bfilter\b/u',
+            'pumpenkopf' => '/\bpumpenkopf\b/u',
+            'motorblock' => '/\bmotorblock\b/u',
+            'mehrwertpaket' => '/\bmehrwertpaket\b/u',
+            'neotecmaster' => '/\bneotecmaster\b/u',
+        ];
+
+        $terms = [];
+
+        foreach ($patterns as $canonical => $pattern) {
+            if (preg_match($pattern, $normalized) === 1) {
+                $terms[] = $canonical;
+            }
+        }
+
+        return array_values(array_unique($terms));
+    }
+
+    /**
+     * @param string[] $left
+     * @param string[] $right
+     * @return string[]
+     */
+    private function mergeFocusTerms(array $left, array $right): array
+    {
+        $merged = [];
+
+        foreach ([$left, $right] as $list) {
+            foreach ($list as $item) {
+                if (!is_string($item)) {
+                    continue;
+                }
+
+                $item = trim($item);
+
+                if ($item === '') {
+                    continue;
+                }
+
+                $merged[$item] = $item;
+            }
+        }
+
+        return array_values($merged);
+    }
+
+    private function areCompatibleProductNames(string $left, string $right): bool
+    {
+        $left = $this->normalizeName($left);
+        $right = $this->normalizeName($right);
+
+        if ($left === '' || $right === '') {
+            return false;
+        }
+
+        if ($left === $right) {
+            return true;
+        }
+
+        return str_contains($left, $right) || str_contains($right, $left);
+    }
+
+    private function normalizeName(string $value): string
+    {
+        $value = mb_strtolower(trim($value), 'UTF-8');
+        $value = preg_replace('/[^\p{L}\p{N}]+/u', ' ', $value) ?? $value;
+        $value = preg_replace('/\s+/u', ' ', $value) ?? $value;
+
+        return trim($value);
+    }
+
+    private function normalizeText(string $value): string
+    {
+        $value = mb_strtolower(trim($value), 'UTF-8');
+        $value = preg_replace('/\s+/u', ' ', $value) ?? $value;
+
+        return trim($value);
+    }
+
+    /**
+     * @param array<string, mixed> $row
+     */
+    private function extractString(array $row, string $key): string
+    {
+        $value = $row[$key] ?? null;
+
+        if (!is_string($value)) {
+            return '';
+        }
+
+        return trim($value);
+    }
+}

src/Commerce/CommerceReferenceStore.php

@@ -0,0 +1,99 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Commerce;
+
+use App\Commerce\Dto\CommerceReferenceContext;
+
+final readonly class CommerceReferenceStore
+{
+    private string $directory;
+
+    public function __construct(string $projectDir)
+    {
+        $this->directory = rtrim($projectDir, '/') . '/var/agent-commerce-context';
+
+        if (!is_dir($this->directory) && !mkdir($this->directory, 0775, true) && !is_dir($this->directory)) {
+            throw new \RuntimeException(sprintf(
+                'Failed to create commerce reference directory: %s',
+                $this->directory
+            ));
+        }
+    }
+
+    public function load(string $userId): ?CommerceReferenceContext
+    {
+        $path = $this->getPath($userId);
+
+        if (!is_file($path)) {
+            return null;
+        }
+
+        $content = file_get_contents($path);
+
+        if ($content === false || trim($content) === '') {
+            return null;
+        }
+
+        $decoded = json_decode($content, true);
+
+        if (!is_array($decoded)) {
+            return null;
+        }
+
+        return CommerceReferenceContext::fromArray($decoded);
+    }
+
+    public function save(string $userId, CommerceReferenceContext $context): void
+    {
+        $path = $this->getPath($userId);
+        $tmpPath = $path . '.tmp';
+
+        $json = json_encode(
+            $context->toArray(),
+            JSON_PRETTY_PRINT | JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_INVALID_UTF8_SUBSTITUTE
+        );
+
+        if (!is_string($json)) {
+            throw new \RuntimeException('Failed to encode commerce reference context.');
+        }
+
+        if (file_put_contents($tmpPath, $json, LOCK_EX) === false) {
+            throw new \RuntimeException(sprintf(
+                'Failed to write commerce reference context: %s',
+                $tmpPath
+            ));
+        }
+
+        if (!rename($tmpPath, $path)) {
+            @unlink($tmpPath);
+
+            throw new \RuntimeException(sprintf(
+                'Failed to move commerce reference context into place: %s',
+                $path
+            ));
+        }
+    }
+
+    public function clear(string $userId): void
+    {
+        $path = $this->getPath($userId);
+
+        if (is_file($path)) {
+            @unlink($path);
+        }
+    }
+
+    private function getPath(string $userId): string
+    {
+        $safeUserId = preg_replace('/[^a-zA-Z0-9_-]/', '_', trim($userId));
+        $safeUserId = is_string($safeUserId) ? trim($safeUserId, '_') : '';
+
+        if ($safeUserId === '') {
+            throw new \InvalidArgumentException('User id must not be empty.');
+        }
+
+        return $this->directory . '/' . $safeUserId . '.json';
+    }
+}

src/Commerce/Dto/CommerceReferenceContext.php

@@ -0,0 +1,149 @@
+<?php
+
+declare(strict_types=1);
+
+namespace App\Commerce\Dto;
+
+final readonly class CommerceReferenceContext
+{
+    /**
+     * @param string[] $focusTerms
+     */
+    public function __construct(
+        public string $productName,
+        public ?string $productNumber = null,
+        public ?string $manufacturer = null,
+        public ?string $url = null,
+        public string $sourceType = 'conversation',
+        public float $confidence = 0.0,
+        public ?string $resolvedFromPrompt = null,
+        public ?string $resolvedAt = null,
+        public array $focusTerms = [],
+    ) {
+    }
+
+    /**
+     * @param array<string, mixed> $payload
+     */
+    public static function fromArray(array $payload): ?self
+    {
+        $productName = self::normalizeNullableString($payload['productName'] ?? null);
+
+        if ($productName === null) {
+            return null;
+        }
+
+        return new self(
+            productName: $productName,
+            productNumber: self::normalizeNullableString($payload['productNumber'] ?? null),
+            manufacturer: self::normalizeNullableString($payload['manufacturer'] ?? null),
+            url: self::normalizeNullableString($payload['url'] ?? null),
+            sourceType: self::normalizeNullableString($payload['sourceType'] ?? null) ?? 'conversation',
+            confidence: isset($payload['confidence']) && is_numeric($payload['confidence']) ? (float) $payload['confidence'] : 0.0,
+            resolvedFromPrompt: self::normalizeNullableString($payload['resolvedFromPrompt'] ?? null),
+            resolvedAt: self::normalizeNullableString($payload['resolvedAt'] ?? null),
+            focusTerms: self::normalizeStringList($payload['focusTerms'] ?? []),
+        );
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    public function toArray(): array
+    {
+        return [
+            'productName' => $this->productName,
+            'productNumber' => $this->productNumber,
+            'manufacturer' => $this->manufacturer,
+            'url' => $this->url,
+            'sourceType' => $this->sourceType,
+            'confidence' => $this->confidence,
+            'resolvedFromPrompt' => $this->resolvedFromPrompt,
+            'resolvedAt' => $this->resolvedAt,
+            'focusTerms' => $this->focusTerms,
+        ];
+    }
+
+    public function hasStrongIdentity(): bool
+    {
+        return $this->productNumber !== null || $this->confidence >= 0.8;
+    }
+
+    public function buildReferenceSearchText(): string
+    {
+        $parts = [];
+
+        if ($this->productName !== '') {
+            $parts[] = $this->productName;
+        }
+
+        if (
+            $this->productNumber !== null
+            && $this->productNumber !== ''
+            && stripos($this->productName, $this->productNumber) === false
+        ) {
+            $parts[] = $this->productNumber;
+        }
+
+        foreach ($this->focusTerms as $focusTerm) {
+            if ($focusTerm === '') {
+                continue;
+            }
+
+            $alreadyIncluded = false;
+
+            foreach ($parts as $part) {
+                if (stripos($part, $focusTerm) !== false) {
+                    $alreadyIncluded = true;
+                    break;
+                }
+            }
+
+            if (!$alreadyIncluded) {
+                $parts[] = $focusTerm;
+            }
+        }
+
+        return trim(implode(' ', $parts));
+    }
+
+    private static function normalizeNullableString(mixed $value): ?string
+    {
+        if (!is_string($value)) {
+            return null;
+        }
+
+        $value = trim($value);
+
+        return $value !== '' ? $value : null;
+    }
+
+    /**
+     * @param mixed $value
+     * @return string[]
+     */
+    private static function normalizeStringList(mixed $value): array
+    {
+        if (!is_array($value)) {
+            return [];
+        }
+
+        $out = [];
+
+        foreach ($value as $item) {
+            if (!is_string($item)) {
+                continue;
+            }
+
+            $item = trim($item);
+
+            if ($item === '') {
+                continue;
+            }
+
+            $out[] = $item;
+        }
+
+        return array_values(array_unique($out));
+    }
+}

src/Config/CommerceIntentConfig.php

@@ -12,27 +12,48 @@ final class CommerceIntentConfig
             'shop',
             'alle',
             'preis',
+            'preise',
             'kunde',
             'online',
             'produkt',
+            'produkte',
             'artikel',
             'sku',
             'kaufen',
             'kostet',
+            'kosten',
+            'verfügbarkeit',
+            'verfuegbarkeit',
 
             // Search / product discovery signals
             'suche',
             'such',
             'finde',
             'finden',
+            'welche',
+            'welcher',
+            'welches',
 
-            // Product-type signals for technical/commercial requests
+            // Device / system signals
             'analysegerät',
             'analysegeraet',
+            'analysegeräte',
+            'analysegeraete',
             'messgerät',
             'messgeraet',
+            'messgeräte',
+            'messgeraete',
+            'gerät',
+            'geraet',
+            'geräte',
+            'geraete',
             'analysator',
+            'analysatoren',
             'analyzer',
+            'system',
+            'systeme',
+            'anlage',
+            'anlagen',
         ];
     }
 
@@ -46,6 +67,8 @@ final class CommerceIntentConfig
             'geeignet',
             'empfiehl',
             'empfehl',
+            'vergleich',
+            'vergleichen',
         ];
     }
 
@@ -57,6 +80,7 @@ final class CommerceIntentConfig
             'eur',
             'teuer',
             'preis',
+            'preise',
             'kosten',
             'kostet',
         ];

src/Config/CommerceQueryParserConfig.php

@@ -1,63 +1,94 @@
 <?php
 
+declare(strict_types=1);
+
 namespace App\Config;
 
-class CommerceQueryParserConfig
+final readonly class CommerceQueryParserConfig
 {
-    public function getKnownBrands(): array
+    /**
-    {
+     * @param string[] $knownBrands
-        return [
+     * @param string[] $phrasesToRemove
-            'heyl',
+     * @param string[] $filterSearchTokensPattern
-            'horiba',
+     * @param string[] $referenceOnlyTokens
-            'neomeris'
+     */
-        ];
+    public function __construct(
+        private array $knownBrands = [],
+        private array $phrasesToRemove = [],
+        private array $filterSearchTokensPattern = [],
+        private array $referenceOnlyTokens = [],
+    ) {
     }
 
+    /**
+     * @return string[]
+     */
+    public function getKnownBrands(): array
+    {
+        return $this->knownBrands;
+    }
+
+    /**
+     * @return string[]
+     */
     public function getPhrasesToRemove(): array
     {
-        return [
+        return $this->phrasesToRemove;
-            'ich suche',
-            'suche',
-            'habt ihr',
-            'gibt es',
-            'zeige mir',
-            'welches gerät',
-            'welche gerät',
-            'welches modell',
-            'welches ist besser',
-            'welches ist am besten',
-            'alternative',
-            'alternativen',
-        ];
     }
 
     public function getHistoryContextPattern(): string
     {
-        return 'chat|auch|noch|nochmal|zusätzlich|dazu|davon|stattdessen|alternative|alternativen|größer|groesser|kleiner|gleich(?:e|en|er|es)?|derselbe|dieselbe|dasselbe|wie oben|wie zuvor|wie gehabt';
+        return 'auch|noch|nochmal|dazu|wie oben|wie zuvor|ähnlich|aehnlich|stattdessen|alternative|alternativ|gerät|geraet|das gerät|das geraet|dieses gerät|dieses geraet|das modell|dieses modell|dafür|dafuer|davon|preis|preise|preis dazu|preis dafür|preis dafuer|preis zum gerät|preis zum geraet|was kostet das|was kostet das gerät|was kostet das geraet|und der preis|kosten|verfügbarkeit|verfuegbarkeit|link dazu|shop|bitte';
     }
 
+    public function getReferenceFollowUpPattern(): string
+    {
+        return 'preis|preise|preis dazu|preis dafür|preis dafuer|preis zum gerät|preis zum geraet|was kostet das|was kostet das gerät|was kostet das geraet|gerät|geraet|das gerät|das geraet|dieses gerät|dieses geraet|das modell|dieses modell|dafür|dafuer|davon|verfügbarkeit|verfuegbarkeit|link dazu|shop|bitte';
+    }
+
+    /**
+     * @return string[]
+     */
     public function getFilterSearchTokensPattern(): array
     {
+        return $this->filterSearchTokensPattern;
+    }
+
+    /**
+     * @return string[]
+     */
+    public function getReferenceOnlyTokens(): array
+    {
+        if ($this->referenceOnlyTokens !== []) {
+            return $this->referenceOnlyTokens;
+        }
+
         return [
-            'auch',
+            'preis',
-            'noch',
+            'preise',
-            'nochmal',
+            'kosten',
-            'zusätzlich',
+            'kostet',
+            'gerät',
+            'geraet',
+            'modell',
+            'produkt',
+            'artikel',
+            'dafür',
+            'dafuer',
             'dazu',
             'davon',
-            'stattdessen',
+            'verfügbarkeit',
+            'verfuegbarkeit',
+            'shop',
+            'link',
+            'zum',
+            'zur',
+            'das',
+            'dieses',
+            'den',
+            'dem',
             'bitte',
-            'gern',
+            'und',
-            'gerne',
-            'zeige',
-            'zeig',
-            'such',
-            'suche',
-            'finde',
-            'find',
-            'mir',
-            'mal',
-            'von',
         ];
     }
 }

src/Config/ShopServiceConfig.php

@@ -1,46 +1,78 @@
 <?php
 
+declare(strict_types=1);
+
 namespace App\Config;
 
-class ShopServiceConfig
+final class ShopServiceConfig
 {
     public const DEVICE_QUERY_KEYWORDS = [
         'analysegerät',
         'analysegeraet',
+        'analysegeräte',
+        'analysegeraete',
         'messgerät',
         'messgeraet',
+        'messgeräte',
+        'messgeraete',
         'analysator',
+        'analysatoren',
         'analyzer',
         'gerät',
         'geraet',
+        'geräte',
+        'geraete',
         'monitor',
+        'monitore',
+        'controller',
         'controller',
         'gerät für',
         'geraet fuer',
+        'geräte für',
+        'geraete fuer',
+        'system',
+        'systeme',
+        'anlage',
+        'anlagen',
     ];
 
     public const ACCESSORY_QUERY_KEYWORDS = [
         'zubehör',
         'zubehor',
         'reagenz',
+        'reagenzien',
         'reagent',
         'indikator',
+        'indikatoren',
         'indicator',
         'kit',
         'set',
         'ersatz',
+        'ersatzteil',
+        'ersatzteile',
         'verbrauchsmaterial',
         'consumable',
         'dazu',
         'passend',
         'passende',
         'passendes',
+        'nachfüll',
+        'nachfuell',
+        'refill',
+        'filter',
+        'pumpenkopf',
+        'motorblock',
+        'service set',
+        'serviceset',
+        'service-set',
     ];
 
     public const ACCESSORY_PRODUCT_KEYWORDS = [
         'reagenz',
+        'reagenzien',
         'reagent',
         'indikator',
+        'indikatoren',
         'indicator',
         'kit',
         'set',
@@ -49,6 +81,8 @@ class ShopServiceConfig
         'zubehör',
         'zubehor',
         'ersatz',
+        'ersatzteil',
+        'ersatzteile',
         'nachfüll',
         'nachfuell',
         'refill',
@@ -57,22 +91,44 @@ class ShopServiceConfig
         'solution',
         'teststreifen',
         'test strip',
+        'filter',
+        'pumpenkopf',
+        'motorblock',
+        'service set',
+        'serviceset',
+        'service-set',
     ];
 
     public const DEVICE_PRODUCT_KEYWORDS = [
         'analysegerät',
         'analysegeraet',
+        'analysegeräte',
+        'analysegeraete',
         'messgerät',
         'messgeraet',
+        'messgeräte',
+        'messgeraete',
         'analysator',
+        'analysatoren',
         'analyzer',
         'monitor',
+        'monitore',
         'controller',
         'online-analysator',
         'online analysator',
         'online-analysegerät',
         'online analysegeraet',
+        'online-analysegeräte',
+        'online analysegeraete',
         'online analyzer',
         'online monitor',
+        'system',
+        'systeme',
+        'anlage',
+        'anlagen',
+        'gerät',
+        'geraet',
+        'geräte',
+        'geraete',
     ];
 }

src/Controller/HistoryController.php

@@ -4,6 +4,7 @@ declare(strict_types=1);
 
 namespace App\Controller;
 
+use App\Commerce\CommerceReferenceStore;
 use App\Context\ContextService;
 use App\Http\ClientIdResolver;
 use Symfony\Component\HttpFoundation\JsonResponse;
@@ -27,9 +28,11 @@ use Symfony\Component\Routing\Annotation\Route;
 final readonly class HistoryController
 {
     public function __construct(
-        private ContextService   $contextService,
+        private ContextService $contextService,
         private ClientIdResolver $clientIdResolver,
-    ) {}
+        private CommerceReferenceStore $commerceReferenceStore,
+    ) {
+    }
 
     /**
      * Returns the full conversation history for the current client
@@ -101,10 +104,11 @@ final readonly class HistoryController
         $clientId = $this->clientIdResolver->resolve($request, $response);
 
         $this->contextService->deleteHistory($clientId);
+        $this->commerceReferenceStore->clear($clientId);
 
         return $this->jsonWithCookies(
             [
-                'status'  => 'ok',
+                'status' => 'ok',
                 'message' => 'History deleted',
             ],
             $response
@@ -113,6 +117,8 @@ final readonly class HistoryController
 
     /**
      * Helper to return JSON responses while forwarding cookies.
+     *
+     * @param array<string, mixed>|array<int, array<string, string>> $data
      */
     private function jsonWithCookies(array $data, Response $cookieResponse): JsonResponse
     {
@@ -124,4 +130,4 @@ final readonly class HistoryController
 
         return $json;
     }
-}
+}

src/Shopware/StoreApiClient.php

@@ -6,7 +6,6 @@ namespace App\Shopware;
 
 use RuntimeException;
 use Symfony\Contracts\HttpClient\Exception\ClientExceptionInterface;
-use Symfony\Contracts\HttpClient\Exception\DecodingExceptionInterface;
 use Symfony\Contracts\HttpClient\Exception\RedirectionExceptionInterface;
 use Symfony\Contracts\HttpClient\Exception\ServerExceptionInterface;
 use Symfony\Contracts\HttpClient\Exception\TransportExceptionInterface;
@@ -31,6 +30,16 @@ final readonly class StoreApiClient
     public function searchProducts(array $criteria): array
     {
         $url = rtrim($this->baseUrl, '/') . '/store-api/search';
+        $sanitizedCriteria = $this->sanitizeValue($criteria);
+
+        $body = json_encode(
+            $sanitizedCriteria,
+            JSON_UNESCAPED_SLASHES | JSON_UNESCAPED_UNICODE | JSON_INVALID_UTF8_SUBSTITUTE
+        );
+
+        if (!is_string($body)) {
+            throw new RuntimeException('Failed to encode Store API criteria.');
+        }
 
         $response = $this->httpClient->request('POST', $url, [
             'headers' => [
@@ -38,12 +47,13 @@ final readonly class StoreApiClient
                 'Accept' => 'application/json',
                 'sw-access-key' => $this->salesChannelAccessKey,
             ],
-            'json' => $criteria,
+            'body' => $body,
             'timeout' => $this->timeoutSeconds,
         ]);
 
         $statusCode = $response->getStatusCode();
         $content = $response->getContent(false);
+        $content = $this->sanitizeString($content);
 
         if ($statusCode < 200 || $statusCode >= 300) {
             throw new RuntimeException(sprintf(
@@ -61,4 +71,48 @@ final readonly class StoreApiClient
 
         return $data;
     }
+
+    private function sanitizeValue(mixed $value): mixed
+    {
+        if (is_array($value)) {
+            $out = [];
+
+            foreach ($value as $key => $item) {
+                $out[$key] = $this->sanitizeValue($item);
+            }
+
+            return $out;
+        }
+
+        if (!is_string($value)) {
+            return $value;
+        }
+
+        return $this->sanitizeString($value);
+    }
+
+    private function sanitizeString(string $value): string
+    {
+        if (preg_match('//u', $value) === 1) {
+            return $value;
+        }
+
+        if (function_exists('mb_convert_encoding')) {
+            $value = mb_convert_encoding($value, 'UTF-8', 'UTF-8');
+        }
+
+        if (preg_match('//u', $value) === 1) {
+            return $value;
+        }
+
+        if (function_exists('iconv')) {
+            $converted = @iconv('UTF-8', 'UTF-8//IGNORE', $value);
+
+            if (is_string($converted) && $converted !== '') {
+                return $converted;
+            }
+        }
+
+        return '';
+    }
 }