diff --git a/src/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModel.php b/src/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModel.php
index e0e2e71b..e3cc9063 100644
--- a/src/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModel.php
+++ b/src/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModel.php
@@ -206,45 +206,55 @@ protected function prepareGenerateTextParams(array $prompt): array
      */
     protected function prepareMessagesParam(array $messages, ?string $systemInstruction = null): array
     {
-        $messagesParam = array_map(
-            function (Message $message): array {
-                // Special case: Function response.
-                $messageParts = $message->getParts();
-                if (count($messageParts) === 1 && $messageParts[0]->getType()->isFunctionResponse()) {
-                    $functionResponse = $messageParts[0]->getFunctionResponse();
+        $messagesParam = [];
+        foreach ($messages as $message) {
+            // Special case: Function responses must be sent as separate tool messages.
+            $messageParts = $message->getParts();
+            if (
+                !empty($messageParts)
+                && count(array_filter(
+                    $messageParts,
+                    static function (MessagePart $part): bool {
+                        return $part->getType()->isFunctionResponse();
+                    }
+                )) === count($messageParts)
+            ) {
+                foreach ($messageParts as $messagePart) {
+                    $functionResponse = $messagePart->getFunctionResponse();
                     if (!$functionResponse) {
                         // This should be impossible due to class internals, but still needs to be checked.
                         throw new RuntimeException(
                             'The function response typed message part must contain a function response.'
                         );
                     }
-                    return [
+                    $messagesParam[] = [
                         'role' => 'tool',
                         'content' => json_encode($functionResponse->getResponse()),
                         'tool_call_id' => $functionResponse->getId(),
                     ];
                 }
-                $messageData = [
-                    'role' => $this->getMessageRoleString($message->getRole()),
-                    'content' => array_values(array_filter(array_map(
-                        [$this, 'getMessagePartContentData'],
-                        $messageParts
-                    ))),
-                ];
+                continue;
+            }
 
-                // Only include tool_calls if there are any (OpenAI rejects empty arrays).
-                $toolCalls = array_values(array_filter(array_map(
-                    [$this, 'getMessagePartToolCallData'],
+            $messageData = [
+                'role' => $this->getMessageRoleString($message->getRole()),
+                'content' => array_values(array_filter(array_map(
+                    [$this, 'getMessagePartContentData'],
                     $messageParts
-                )));
-                if (!empty($toolCalls)) {
-                    $messageData['tool_calls'] = $toolCalls;
-                }
+                ))),
+            ];
 
-                return $messageData;
-            },
-            $messages
-        );
+            // Only include tool_calls if there are any (OpenAI rejects empty arrays).
+            $toolCalls = array_values(array_filter(array_map(
+                [$this, 'getMessagePartToolCallData'],
+                $messageParts
+            )));
+            if (!empty($toolCalls)) {
+                $messageData['tool_calls'] = $toolCalls;
+            }
+
+            $messagesParam[] = $messageData;
+        }
 
         if ($systemInstruction) {
             array_unshift(
diff --git a/tests/unit/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModelTest.php b/tests/unit/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModelTest.php
index 6c99c75b..37d23f9f 100644
--- a/tests/unit/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModelTest.php
+++ b/tests/unit/Providers/OpenAiCompatibleImplementation/AbstractOpenAiCompatibleTextGenerationModelTest.php
@@ -548,6 +548,33 @@ public function testPrepareMessagesParamFunctionResponse(): void
         $this->assertEquals('call_1', $prepared[0]['tool_call_id']);
     }
 
+    /**
+     * Tests prepareMessagesParam() with multiple function responses in one message.
+     *
+     * @return void
+     */
+    public function testPrepareMessagesParamMultipleFunctionResponses(): void
+    {
+        $message = new Message(
+            MessageRoleEnum::user(),
+            [
+                new MessagePart(new FunctionResponse('call_1', 'first_function', ['result' => 'first'])),
+                new MessagePart(new FunctionResponse('call_2', 'second_function', ['result' => 'second'])),
+            ]
+        );
+        $model = $this->createModel();
+
+        $prepared = $model->exposePrepareMessagesParam([$message]);
+
+        $this->assertCount(2, $prepared);
+        $this->assertSame('tool', $prepared[0]['role']);
+        $this->assertSame(json_encode(['result' => 'first']), $prepared[0]['content']);
+        $this->assertSame('call_1', $prepared[0]['tool_call_id']);
+        $this->assertSame('tool', $prepared[1]['role']);
+        $this->assertSame(json_encode(['result' => 'second']), $prepared[1]['content']);
+        $this->assertSame('call_2', $prepared[1]['tool_call_id']);
+    }
+
     /**
      * Tests getMessageRoleString() method.
      *