feat: extract thinking blocks from LLM responses

Classes/Domain/Model/CompletionResponse.php

@@ -26,6 +26,7 @@ public function __construct(
         public string $provider = '',
         public ?array $toolCalls = null,
         public ?array $metadata = null,
+        public ?string $thinking = null,
     ) {}
 
     /**
@@ -60,6 +61,14 @@ public function hasToolCalls(): bool
         return $this->toolCalls !== null && $this->toolCalls !== [];
     }
 
+    /**
+     * Check if the response contains thinking/reasoning content.
+     */
+    public function hasThinking(): bool
+    {
+        return $this->thinking !== null && trim($this->thinking) !== '';
+    }
+
     /**
      * Get the text content (alias for content property).
      */

Classes/Provider/AbstractProvider.php

@@ -316,16 +316,37 @@ protected function createCompletionResponse(
         string $model,
         UsageStatistics $usage,
         ?string $finishReason = null,
+        ?string $thinking = null,
     ): CompletionResponse {
         return new CompletionResponse(
             content: $content,
             model: $model,
             usage: $usage,
             finishReason: $finishReason ?? 'stop',
             provider: $this->getIdentifier(),
+            thinking: $thinking,
         );
     }
 
+    /**
+     * Extract and remove <think>...</think> blocks from content.
+     *
+     * @return array{string, string|null} [cleanContent, thinkingContent]
+     */
+    protected function extractThinkingBlocks(string $content): array
+    {
+        $thinking = null;
+        if (preg_match_all('#<think>([\s\S]*?)</think>#i', $content, $matches)) {
+            $thinking = trim(implode("\n", $matches[1]));
+            // Replace with space to prevent word-gluing (e.g. "foo<think>...</think>bar" → "foo bar")
+            $cleaned = preg_replace('#<think>[\s\S]*?</think>#i', ' ', $content) ?? $content;
+            // Normalize horizontal whitespace (spaces/tabs) but preserve newlines for formatting
+            $content = trim((string)preg_replace('/[ \t]+/', ' ', $cleaned));
+        }
+
+        return [$content, $thinking !== '' ? $thinking : null];
+    }
+
     /**
      * @param array<int, array<int, float>> $embeddings
      */

Classes/Provider/ClaudeProvider.php

@@ -146,14 +146,22 @@ public function chatCompletion(array $messages, array $options = []): Completion
         $response = $this->sendRequest('messages', $payload);
 
         $content = '';
+        $nativeThinkingBlocks = [];
         $contentBlocks = $this->getList($response, 'content');
         foreach ($contentBlocks as $block) {
             $blockArray = $this->asArray($block);
-            if ($this->getString($blockArray, 'type') === 'text') {
+            $blockType = $this->getString($blockArray, 'type');
+            if ($blockType === 'text') {
                 $content .= $this->getString($blockArray, 'text');
+            } elseif ($blockType === 'thinking') {
+                $nativeThinkingBlocks[] = $this->getString($blockArray, 'thinking');
             }
         }
 
+        $nativeThinking = implode("\n", $nativeThinkingBlocks);
+        [$content, $inlineThinking] = $this->extractThinkingBlocks($content);
+        $allThinking = trim(($nativeThinking !== '' ? $nativeThinking . "\n" : '') . ($inlineThinking ?? ''));
+
         $usage = $this->getArray($response, 'usage');
 
         return $this->createCompletionResponse(
@@ -164,6 +172,7 @@ public function chatCompletion(array $messages, array $options = []): Completion
                 completionTokens: $this->getInt($usage, 'output_tokens'),
             ),
             finishReason: $this->mapStopReason($this->getString($response, 'stop_reason', 'end_turn')),
+            thinking: $allThinking !== '' ? $allThinking : null,
         );
     }
 
@@ -219,6 +228,7 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
         $response = $this->sendRequest('messages', $payload);
 
         $content = '';
+        $nativeThinkingBlocks = [];
         $toolCalls = [];
 
         $contentBlocks = $this->getList($response, 'content');
@@ -227,6 +237,8 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             $blockType = $this->getString($blockArray, 'type');
             if ($blockType === 'text') {
                 $content .= $this->getString($blockArray, 'text');
+            } elseif ($blockType === 'thinking') {
+                $nativeThinkingBlocks[] = $this->getString($blockArray, 'thinking');
             } elseif ($blockType === 'tool_use') {
                 $toolCalls[] = [
                     'id' => $this->getString($blockArray, 'id'),
@@ -239,6 +251,10 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             }
         }
 
+        $nativeThinking = implode("\n", $nativeThinkingBlocks);
+        [$content, $inlineThinking] = $this->extractThinkingBlocks($content);
+        $allThinking = trim(($nativeThinking !== '' ? $nativeThinking . "\n" : '') . ($inlineThinking ?? ''));
+
         $usage = $this->getArray($response, 'usage');
 
         return new CompletionResponse(
@@ -251,6 +267,7 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             finishReason: $this->mapStopReason($this->getString($response, 'stop_reason', 'end_turn')),
             provider: $this->getIdentifier(),
             toolCalls: $toolCalls !== [] ? $toolCalls : null,
+            thinking: $allThinking !== '' ? $allThinking : null,
         );
     }
 

Classes/Provider/GeminiProvider.php

@@ -118,7 +118,8 @@ public function chatCompletion(array $messages, array $options = []): Completion
         $contentObj = $this->getArray($candidate, 'content');
         $parts = $this->getList($contentObj, 'parts');
         $firstPart = $this->asArray($parts[0] ?? []);
-        $content = $this->getString($firstPart, 'text');
+        $rawContent = $this->getString($firstPart, 'text');
+        [$content, $thinking] = $this->extractThinkingBlocks($rawContent);
         $usage = $this->getArray($response, 'usageMetadata');
 
         return $this->createCompletionResponse(
@@ -129,6 +130,7 @@ public function chatCompletion(array $messages, array $options = []): Completion
                 completionTokens: $this->getInt($usage, 'candidatesTokenCount'),
             ),
             finishReason: $this->mapFinishReason($this->getString($candidate, 'finishReason', 'STOP')),
+            thinking: $thinking,
         );
     }
 
@@ -178,14 +180,14 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
         $contentObj = $this->getArray($candidate, 'content');
         $parts = $this->getList($contentObj, 'parts');
 
-        $content = '';
+        $rawContent = '';
         $toolCalls = [];
 
         foreach ($parts as $part) {
             $partArray = $this->asArray($part);
             $text = $this->getNullableString($partArray, 'text');
             if ($text !== null) {
-                $content .= $text;
+                $rawContent .= $text;
             }
 
             $functionCall = $this->getArray($partArray, 'functionCall');
@@ -201,6 +203,7 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             }
         }
 
+        [$content, $thinking] = $this->extractThinkingBlocks($rawContent);
         $usage = $this->getArray($response, 'usageMetadata');
 
         return new CompletionResponse(
@@ -213,6 +216,7 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             finishReason: $this->mapFinishReason($this->getString($candidate, 'finishReason', 'STOP')),
             provider: $this->getIdentifier(),
             toolCalls: $toolCalls !== [] ? $toolCalls : null,
+            thinking: $thinking,
         );
     }
 

Classes/Provider/OpenAiProvider.php

@@ -122,14 +122,17 @@ public function chatCompletion(array $messages, array $options = []): Completion
         $message = $this->getArray($choice, 'message');
         $usage = $this->getArray($response, 'usage');
 
+        [$content, $thinking] = $this->extractThinkingBlocks($this->getString($message, 'content'));
+
         return $this->createCompletionResponse(
-            content: $this->getString($message, 'content'),
+            content: $content,
             model: $this->getString($response, 'model', $model),
             usage: $this->createUsageStatistics(
                 promptTokens: $this->getInt($usage, 'prompt_tokens'),
                 completionTokens: $this->getInt($usage, 'completion_tokens'),
             ),
             finishReason: $this->getString($choice, 'finish_reason', 'stop'),
+            thinking: $thinking,
         );
     }
 
@@ -182,8 +185,10 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             }
         }
 
+        [$content, $thinking] = $this->extractThinkingBlocks($this->getString($message, 'content'));
+
         return new CompletionResponse(
-            content: $this->getString($message, 'content'),
+            content: $content,
             model: $this->getString($response, 'model', $model),
             usage: $this->createUsageStatistics(
                 promptTokens: $this->getInt($usage, 'prompt_tokens'),
@@ -192,6 +197,7 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             finishReason: $this->getString($choice, 'finish_reason', 'stop'),
             provider: $this->getIdentifier(),
             toolCalls: $toolCalls,
+            thinking: $thinking,
         );
     }
 

Classes/Provider/OpenRouterProvider.php

@@ -288,8 +288,10 @@ public function chatCompletion(array $messages, array $options = []): Completion
         $message = $this->getArray($choice, 'message');
         $usage = $this->getArray($response, 'usage');
 
+        [$content, $thinking] = $this->extractThinkingBlocks($this->getString($message, 'content'));
+
         return new CompletionResponse(
-            content: $this->getString($message, 'content'),
+            content: $content,
             model: $this->getString($response, 'model', $model),
             usage: $this->createUsageStatistics(
                 promptTokens: $this->getInt($usage, 'prompt_tokens'),
@@ -305,6 +307,7 @@ public function chatCompletion(array $messages, array $options = []): Completion
                     'completion' => $response['native_tokens_completion'] ?? null,
                 ],
             ],
+            thinking: $thinking,
         );
     }
 
@@ -365,8 +368,10 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
             }
         }
 
+        [$content, $thinking] = $this->extractThinkingBlocks($this->getString($message, 'content'));
+
         return new CompletionResponse(
-            content: $this->getString($message, 'content'),
+            content: $content,
             model: $this->getString($response, 'model', $model),
             usage: $this->createUsageStatistics(
                 promptTokens: $this->getInt($usage, 'prompt_tokens'),
@@ -379,6 +384,7 @@ public function chatCompletionWithTools(array $messages, array $tools, array $op
                 'actual_provider' => $this->getString($response, 'provider', 'unknown'),
                 'cost' => $response['total_cost'] ?? null,
             ],
+            thinking: $thinking,
         );
     }
 

Tests/Unit/Domain/Model/CompletionResponseTest.php

@@ -202,6 +202,72 @@ public function getTextReturnsContent(): void
         self::assertEquals($response->content, $response->getText());
     }
 
+    #[Test]
+    public function constructorSetsThinkingProperty(): void
+    {
+        $usage = new UsageStatistics(100, 50, 150);
+
+        $response = new CompletionResponse(
+            content: 'Hello',
+            model: 'gpt-4o',
+            usage: $usage,
+            thinking: 'I need to think about this',
+        );
+
+        self::assertEquals('I need to think about this', $response->thinking);
+    }
+
+    #[Test]
+    public function thinkingDefaultsToNull(): void
+    {
+        $response = new CompletionResponse(
+            content: 'test',
+            model: 'gpt-4',
+            usage: new UsageStatistics(10, 5, 15),
+        );
+
+        self::assertNull($response->thinking);
+    }
+
+    #[Test]
+    public function hasThinkingReturnsTrueWhenPresent(): void
+    {
+        $response = new CompletionResponse(
+            content: 'result',
+            model: 'gpt-4',
+            usage: new UsageStatistics(10, 20, 30),
+            thinking: 'reasoning content',
+        );
+
+        self::assertTrue($response->hasThinking());
+    }
+
+    #[Test]
+    public function hasThinkingReturnsFalseWhenNull(): void
+    {
+        $response = new CompletionResponse(
+            content: 'result',
+            model: 'gpt-4',
+            usage: new UsageStatistics(10, 20, 30),
+            thinking: null,
+        );
+
+        self::assertFalse($response->hasThinking());
+    }
+
+    #[Test]
+    public function hasThinkingReturnsFalseWhenEmpty(): void
+    {
+        $response = new CompletionResponse(
+            content: 'result',
+            model: 'gpt-4',
+            usage: new UsageStatistics(10, 20, 30),
+            thinking: '',
+        );
+
+        self::assertFalse($response->hasThinking());
+    }
+
     #[Test]
     public function responseIsImmutable(): void
     {