main: 增强工具调用与消息流程

- 支持 tool.call 和 tool.result 消息类型处理
- 引入 Tool 调度与执行逻辑，支持超时与结果截断
- 增加 ToolRegistry 和 ToolExecutor 管理工具定义与执行
- 更新上下文构建与消息映射逻辑，适配工具闭环处理
- 扩展配置与环境变量，支持 Tool 调用相关选项
- 增强单元测试覆盖工具调用与执行情景
- 更新文档和 OpenAPI，新增工具相关说明与模型定义

app/Services/Agent/OpenAi/ChatCompletionsRequestBuilder.php

@@ -4,19 +4,23 @@ namespace App\Services\Agent\OpenAi;
 
 use App\Models\Message;
 use App\Services\Agent\AgentContext;
+use App\Services\Tool\ToolRegistry;
 
 class ChatCompletionsRequestBuilder
 {
     public function __construct(
+        private readonly ToolRegistry $toolRegistry,
         private ?string $model = null,
         private ?float $temperature = null,
         private ?float $topP = null,
         private ?bool $includeUsage = null,
+        private ?string $toolChoice = null,
     ) {
         $this->model = $this->model ?? (string) config('agent.openai.model', 'gpt-4o-mini');
         $this->temperature = $this->temperature ?? (float) config('agent.openai.temperature', 0.7);
         $this->topP = $this->topP ?? (float) config('agent.openai.top_p', 1.0);
         $this->includeUsage = $this->includeUsage ?? (bool) config('agent.openai.include_usage', false);
+        $this->toolChoice = $this->toolChoice ?? (string) config('agent.tools.tool_choice', 'auto');
     }
 
     /**
@@ -63,11 +67,18 @@ class ChatCompletionsRequestBuilder
             $payload['response_format'] = $options['response_format'];
         }
 
+        $toolsSpec = $this->toolRegistry->openAiToolsSpec();
+
+        if (! empty($toolsSpec)) {
+            $payload['tools'] = $toolsSpec;
+            $payload['tool_choice'] = $options['tool_choice'] ?? $this->toolChoice ?? 'auto';
+        }
+
         return $payload;
     }
 
     /**
-     * @return array<int, array{role: string, content: string}>
+     * @return array<int, array<string, mixed>>
      */
     private function buildMessages(AgentContext $context): array
     {
@@ -83,15 +94,35 @@ class ChatCompletionsRequestBuilder
         foreach ($context->messages as $message) {
             $role = $this->mapRole((string) ($message['role'] ?? ''));
             $content = $message['content'] ?? null;
+            $type = (string) ($message['type'] ?? '');
+            $payload = $message['payload'] ?? null;
 
             if (! $role || ! is_string($content) || $content === '') {
+                $content = null;
+            }
+
+            if ($type === 'tool.call' && is_array($payload)) {
+                $toolCall = $this->normalizeToolCallPayload($payload, $content);
+                if ($toolCall) {
+                    $messages[] = $toolCall;
+                }
                 continue;
             }
 
-            $messages[] = [
-                'role' => $role,
-                'content' => $content,
-            ];
+            if ($type === 'tool.result' && is_array($payload)) {
+                $toolResult = $this->normalizeToolResultPayload($payload, $content);
+                if ($toolResult) {
+                    $messages[] = $toolResult;
+                }
+                continue;
+            }
+
+            if ($content !== null) {
+                $messages[] = [
+                    'role' => $role,
+                    'content' => $content,
+                ];
+            }
         }
 
         return $messages;
@@ -106,4 +137,63 @@ class ChatCompletionsRequestBuilder
             default => null,
         };
     }
+
+    /**
+     * @param array<string, mixed> $payload
+     * @return array<string, mixed>|null
+     */
+    private function normalizeToolCallPayload(array $payload, ?string $content): ?array
+    {
+        $toolCallId = $payload['tool_call_id'] ?? null;
+        $name = $payload['name'] ?? null;
+        $arguments = $payload['arguments'] ?? null;
+
+        if (! is_string($toolCallId) || ! is_string($name) || $toolCallId === '' || $name === '') {
+            return null;
+        }
+
+        $argumentsString = is_string($arguments) ? $arguments : json_encode($arguments, JSON_UNESCAPED_UNICODE);
+
+        return [
+            'role' => 'assistant',
+            'content' => $content,
+            'tool_calls' => [
+                [
+                    'id' => $toolCallId,
+                    'type' => 'function',
+                    'function' => [
+                        'name' => $name,
+                        'arguments' => $argumentsString ?? '',
+                    ],
+                ],
+            ],
+        ];
+    }
+
+    /**
+     * @param array<string, mixed> $payload
+     * @return array<string, mixed>|null
+     */
+    private function normalizeToolResultPayload(array $payload, ?string $content): ?array
+    {
+        $toolCallId = $payload['tool_call_id'] ?? null;
+        $name = $payload['name'] ?? null;
+
+        if (! is_string($toolCallId) || $toolCallId === '') {
+            return null;
+        }
+
+        $resultContent = $content ?? ($payload['output'] ?? null);
+
+        if (! is_string($resultContent)) {
+            $resultContent = json_encode($payload['output'] ?? $payload, JSON_UNESCAPED_UNICODE);
+        }
+
+        return [
+            'role' => 'tool',
+            'tool_call_id' => $toolCallId,
+            'name' => is_string($name) ? $name : null,
+            'content' => $resultContent,
+        ];
+    }
 }

app/Services/Agent/OpenAi/OpenAiEventNormalizer.php

@@ -35,6 +35,25 @@ class OpenAiEventNormalizer
             if (is_string($content) && $content !== '') {
                 $events[] = ProviderEvent::messageDelta($content);
             }
+
+            if (isset($delta['tool_calls']) && is_array($delta['tool_calls'])) {
+                $toolCalls = [];
+                foreach ($delta['tool_calls'] as $toolCall) {
+                    if (! is_array($toolCall)) {
+                        continue;
+                    }
+                    $toolCalls[] = [
+                        'id' => $toolCall['id'] ?? null,
+                        'name' => $toolCall['function']['name'] ?? null,
+                        'arguments' => $toolCall['function']['arguments'] ?? '',
+                        'index' => $toolCall['index'] ?? null,
+                    ];
+                }
+
+                if (! empty($toolCalls)) {
+                    $events[] = ProviderEvent::toolDelta(['tool_calls' => $toolCalls]);
+                }
+            }
         }
 
         if (is_array($firstChoice) && array_key_exists('finish_reason', $firstChoice) && $firstChoice['finish_reason'] !== null) {