fix: flaky anthropic tool calls with empty text (#315)

Fixes #313

Author: chr-hertel

src/Bridge/Anthropic/ModelHandler.php

@@ -121,16 +121,17 @@ public function convert(ResponseInterface $response, array $options = []): LlmRe
             throw new RuntimeException('Response does not contain any content');
         }
 
-        if (!isset($data['content'][0]['text'])) {
-            throw new RuntimeException('Response content does not contain any text');
-        }
-
         $toolCalls = [];
         foreach ($data['content'] as $content) {
             if ('tool_use' === $content['type']) {
                 $toolCalls[] = new ToolCall($content['id'], $content['name'], $content['input']);
             }
         }
+
+        if (!isset($data['content'][0]['text']) && 0 === count($toolCalls)) {
+            throw new RuntimeException('Response content does not contain any text nor tool calls.');
+        }
+
         if (!empty($toolCalls)) {
             return new ToolCallResponse(...$toolCalls);
         }

tests/Bridge/Anthropic/ModelHandlerTest.php

@@ -0,0 +1,39 @@
+<?php
+
+declare(strict_types=1);
+
+namespace PhpLlm\LlmChain\Tests\Bridge\Anthropic;
+
+use PhpLlm\LlmChain\Bridge\Anthropic\ModelHandler;
+use PhpLlm\LlmChain\Model\Response\ToolCallResponse;
+use PHPUnit\Framework\Attributes\CoversClass;
+use PHPUnit\Framework\TestCase;
+use Symfony\Component\HttpClient\MockHttpClient;
+use Symfony\Component\HttpClient\Response\JsonMockResponse;
+
+#[CoversClass(ModelHandler::class)]
+final class ModelHandlerTest extends TestCase
+{
+    public function testConvertThrowsExceptionWhenContentIsToolUseAndLacksText(): void
+    {
+        $httpClient = new MockHttpClient(new JsonMockResponse([
+            'content' => [
+                [
+                    'type' => 'tool_use',
+                    'id' => 'toolu_01UM4PcTjC1UDiorSXVHSVFM',
+                    'name' => 'xxx_tool',
+                    'input' => ['action' => 'get_data'],
+                ],
+            ],
+        ]));
+        $httpResponse = $httpClient->request('POST', 'https://api.anthropic.com/v1/messages');
+        $handler = new ModelHandler($httpClient, 'test-api-key');
+
+        $response = $handler->convert($httpResponse);
+        self::assertInstanceOf(ToolCallResponse::class, $response);
+        self::assertCount(1, $response->getContent());
+        self::assertSame('toolu_01UM4PcTjC1UDiorSXVHSVFM', $response->getContent()[0]->id);
+        self::assertSame('xxx_tool', $response->getContent()[0]->name);
+        self::assertSame(['action' => 'get_data'], $response->getContent()[0]->arguments);
+    }
+}