What is the problem?
接 Anthropic Claude API 的正确做法：用 @anthropic-ai/sdk、Messages API（必须传 max_tokens、system 是顶层参数）、key 放服务端 Route Handler、流式返回、处理 401/429/overloaded。附可用代码。
Quick solution
Treat this as a AI tools tutorial issue. First confirm the environment, inputs, permissions, logs, and delivery boundary. Then use the linked deep guide for the full checklist before changing production code or promising a result.
Read the deep guideDetailed steps
- **缺 max_tokens 报错**：Messages API 必须传 `max_tokens`，补上即可。
- **system 放错位置**：别在 `messages` 里放 `{ role: "system" }`，用顶层 `system` 字段。
- **401 authentication_error**：key 错或没读到 → 检查 `.env.local`、重启 dev。
- **429 / overloaded_error**：限流或服务繁忙 → 加指数退避重试；`overloaded` 通常稍后重试即可。
- **生产读不到**：Vercel 没配 `ANTHROPIC_API_KEY` → 补环境变量并重新部署。
- key 只在服务端，泄露立刻在 Anthropic 后台吊销换新。
Commands or code
npm install @anthropic-ai/sdkRisk notes
Confirm the real project environment, account permissions, platform rules, and output quality before delivery. Do not ship AI-generated changes without human review, and do not claim indexing, income, deployment success, or ranking improvements without measured evidence.