config/llm_settings.py

import os
from dotenv import load_dotenv
from typing import Literal

class LLMSettings:
    def __init__(self):
        load_dotenv()
        
        self.openai_api_key = os.getenv('OPENAI_API_KEY')
        self.anthropic_api_key = os.getenv('ANTHROPIC_API_KEY')
        self.default_llm = os.getenv('DEFAULT_LLM', 'claude')
        
        # API キーの存在確認
        if not self.openai_api_key and not self.anthropic_api_key:
            raise ValueError("少なくとも1つのAPIキーが必要です。")
            
    def get_available_models(self) -> list[Literal['claude', 'gpt']]:
        """利用可能なモデルのリストを返す"""
        models = []
        if self.anthropic_api_key:
            models.append('claude')
        if self.openai_api_key:
            models.append('gpt')
        return models