feat: add OpenAI LLM provider

packages/llm/src/providers/openai.ts

@@ -0,0 +1,28 @@
+import OpenAI from "openai";
+import type { LLMMessage, LLMOptions } from "@codeboard/shared";
+import type { LLMProvider } from "./base.js";
+
+export class OpenAIProvider implements LLMProvider {
+  name = "openai";
+  private client: OpenAI;
+  private defaultModel: string;
+
+  constructor(apiKey: string, model?: string, baseUrl?: string) {
+    this.client = new OpenAI({
+      apiKey,
+      baseURL: baseUrl,
+    });
+    this.defaultModel = model ?? "gpt-4o";
+  }
+
+  async chat(messages: LLMMessage[], options?: LLMOptions): Promise<string> {
+    const response = await this.client.chat.completions.create({
+      model: options?.model ?? this.defaultModel,
+      messages: messages.map((m) => ({ role: m.role, content: m.content })),
+      temperature: options?.temperature ?? 0.3,
+      max_tokens: options?.maxTokens ?? 4096,
+    });
+
+    return response.choices[0]?.message?.content ?? "";
+  }
+}