ai-switcher/src/clients/anthropic.ts

A package which helps you switch between AI APIs using configurations, so that code changes are not required.

// src/clients/anthropic.ts
import { Anthropic } from '@anthropic-ai/sdk';
import { Message, CompletionOptions, AIError } from '../types';
import { BaseAIClient } from './base';

export class AnthropicClient extends BaseAIClient {
  private client: Anthropic;
  protected apiKey: string;

  constructor(apiKey: string) {
    super();
    this.apiKey = apiKey;
    this.client = new Anthropic({ apiKey });
  }

  async createCompletion(messages: Message[], options: CompletionOptions = {}): Promise<string> {
    try {
      // Extract system message if present
      const systemMessage = messages.find(msg => msg.role === 'system');
      const nonSystemMessages = messages.filter(msg => msg.role !== 'system');

      const response = await this.client.messages.create({
        model: options.model || 'claude-3-haiku-20240307',
        max_tokens: options.maxTokens || 4096,
        temperature: options.temperature,
        top_p: options.topP,
        stop_sequences: options.stop,
        system: systemMessage?.content,
        messages: nonSystemMessages.map(msg => ({
          role: msg.role as 'user' | 'assistant',
          content: msg.content,
        })),
      });

      if ('error' in response) {
        throw new AIError(`Anthropic error: ${(response.error as any).message}`, 'anthropic');
      }

      // Handle different types of content blocks
      const block = response.content[0];
      if ('text' in block) {
        return block.text;
      }
      throw new AIError('Unsupported response content type', 'anthropic');
    } catch (error: any) {
      // Map Anthropic errors to standardized errors
      if (error?.status === 401) {
        throw new AIError('Invalid API key', 'anthropic', 401, error);
      }
      if (error?.status === 429) {
        throw new AIError('Rate limit exceeded', 'anthropic', 429, error);
      }
      if (error?.status === 400) {
        throw new AIError(error.message || 'Bad request', 'anthropic', 400, error);
      }
      if (error?.status >= 500) {
        throw new AIError('Server error', 'anthropic', error.status, error);
      }
      throw new AIError(error.message || 'Unknown error', 'anthropic', undefined, error);
    }
  }

  async createEmbedding(text: string): Promise<number[]> {
    throw new AIError('Embeddings not supported by Anthropic', 'anthropic');
  }
}