Deploy Anthropic Integration

Overview

Claude integrations are stateless API wrappers — a serverless function receives a user request, streams from the Messages API, and returns the response. No database, no connection pool, no persistent state.

Vercel Edge Function (Recommended)

// app/api/chat/route.ts (Next.js App Router)
import Anthropic from '@claude-ai/sdk';

export const runtime = 'edge';

export async function POST(req: Request) {
  const client = new Anthropic();
  const { messages, system } = await req.json();

  const stream = await client.messages.create({
    model: 'claude-sonnet-4-20250514',
    max_tokens: 4096,
    system: system || 'You are a helpful assistant.',
    messages,
    stream: true,
  });

  // Convert Anthropic stream to ReadableStream for SSE
  const encoder = new TextEncoder();
  const readable = new ReadableStream({
    async start(controller) {
      for await (const event of stream) {
        if (event.type === 'content_block_delta' && event.delta.type === 'text_delta') {
          controller.enqueue(encoder.encode(`data: ${JSON.stringify(event.delta)}\n\n`));
        }
      }
      controller.enqueue(encoder.encode('data: [DONE]\n\n'));
      controller.close();
    },
  });

  return new Response(readable, {
    headers: {
      'Content-Type': 'text/event-stream',
      'Cache-Control': 'no-cache',
    },
  });
}

Instructions

Step 1: Deploy to Vercel

# Add secret
vercel env add ANTHROPIC_API_KEY

# Deploy
vercel --prod

Fly.io (Long-Running / WebSocket)

FROM node:20-slim
WORKDIR /app
COPY package*.json ./
RUN npm ci --only=production
COPY . .
EXPOSE 3000
CMD ["node", "server.js"]

fly launch --name my-claude-app
fly secrets set ANTHROPIC_API_KEY=sk-ant-api03-...
fly deploy

Google Cloud Run

gcloud run deploy claude-api \
  --source . \
  --region us-central1 \
  --allow-unauthenticated \
  --set-secrets=ANTHROPIC_API_KEY=claude-key:latest \
  --timeout=300 \
  --concurrency=80