> ## Documentation Index
> Fetch the complete documentation index at: https://docs.tokenlab.sh/llms.txt
> Use this file to discover all available pages before exploring further.

# 最佳实践

> 优化你的 TokenLab API 使用，以提升成本、性能和可靠性

## 模型选择

选择合适的模型会显著影响成本和质量。

### 基于任务的推荐

| 任务        | 推荐模型                                              | 原因           |
| --------- | ------------------------------------------------- | ------------ |
| **简单问答**  | `gpt-5-mini`, `gemini-3.5-flash`                  | 快速、便宜、足够好用   |
| **复杂推理**  | `gpt-5.4`, `claude-opus-4-6`, `deepseek-r1`       | 更好的逻辑和规划能力   |
| **编程**    | `claude-sonnet-4-6`, `gpt-4o`, `deepseek-v3-2`    | 针对代码进行了优化    |
| **创意写作**  | `claude-sonnet-4-6`, `gpt-4o`                     | 更好的文风质量      |
| **视觉/图像** | `gpt-4o`, `claude-sonnet-4-6`, `gemini-3.5-flash` | 原生视觉支持       |
| **长上下文**  | `gemini-2.5-pro`, `claude-sonnet-4-6`             | 1M+ token 窗口 |
| **成本敏感**  | `gpt-5-mini`, `gemini-3.5-flash`, `deepseek-v3-2` | 性价比最佳        |

### 成本层级

```
$$$$ Premium: gpt-5.4, claude-opus-4-6
$$$  Standard: claude-sonnet-4-6, gpt-4o
$$   Budget:   gpt-5-mini, gemini-3.5-flash
$    Economy:  deepseek-v3-2, deepseek-r1
```

## 成本优化

### 1. 优先使用更小的模型

```python theme={null}
def smart_query(question: str, complexity: str = "auto"):
    """Use cheaper models for simple tasks."""

    if complexity == "simple":
        model = "gpt-5-mini"
    elif complexity == "complex":
        model = "gpt-4o"
    else:
        # Start cheap, escalate if needed
        model = "gpt-5-mini"

    response = client.chat.completions.create(
        model=model,
        messages=[{"role": "user", "content": question}]
    )
    return response
```

### 2. 设置 max\_tokens

始终设置合理的 `max_tokens` 限制：

```python theme={null}
# ❌ Bad: No limit, could generate thousands of tokens
response = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": "Summarize this article"}]
)

# ✅ Good: Limit response length
response = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": "Summarize this article"}],
    max_tokens=500  # Reasonable limit for a summary
)
```

### 3. 优化 Prompt

```python theme={null}
# ❌ Verbose prompt (more input tokens)
prompt = """
I would like you to please help me by analyzing the following text
and providing a comprehensive summary of the main points. Please be
thorough but also concise in your response. The text is as follows:
{text}
"""

# ✅ Concise prompt (fewer tokens)
prompt = "Summarize the key points:\n{text}"
```

### 4. 批量处理相似请求

```python theme={null}
# ❌ Many small requests
for question in questions:
    response = client.chat.completions.create(
        model="gpt-4o",
        messages=[{"role": "user", "content": question}]
    )

# ✅ Fewer larger requests
combined_prompt = "\n".join([f"{i+1}. {q}" for i, q in enumerate(questions)])
response = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": f"Answer each question:\n{combined_prompt}"}]
)
```

## 性能优化

### 5. 为 UX 使用流式输出

流式输出可以改善感知性能：

```python theme={null}
stream = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": "Write a long essay"}],
    stream=True
)

for chunk in stream:
    if chunk.choices[0].delta.content:
        print(chunk.choices[0].delta.content, end="", flush=True)
```

### 6. 为交互式使用选择快速模型

| 使用场景           | 推荐                               | 延迟              |
| -------------- | -------------------------------- | --------------- |
| Chat UI        | `gpt-5-mini`, `gemini-3.5-flash` | \~200ms 首 token |
| Tab completion | `claude-haiku-4-5`               | \~150ms 首 token |
| 后台处理           | `gpt-4o`, `claude-sonnet-4-6`    | \~500ms 首 token |

### 7. 设置超时

```python theme={null}
client = OpenAI(
    api_key="sk-your-key",
    base_url="https://api.tokenlab.sh/v1",
    timeout=60.0  # 60 second timeout
)
```

## 可靠性

### 8. 实现重试机制

```python theme={null}
import time
from openai import RateLimitError, APIError

def chat_with_retry(messages, max_retries=3):
    for attempt in range(max_retries):
        try:
            return client.chat.completions.create(
                model="gpt-4o",
                messages=messages
            )
        except RateLimitError:
            wait = 2 ** attempt
            print(f"Rate limited, waiting {wait}s...")
            time.sleep(wait)
        except APIError as e:
            if attempt == max_retries - 1:
                raise
            time.sleep(1)
    raise Exception("Max retries exceeded")
```

### 9. 优雅地处理错误

```python theme={null}
from openai import APIError, AuthenticationError, RateLimitError

try:
    response = client.chat.completions.create(...)
except AuthenticationError:
    # Check API key
    notify_admin("Invalid API key")
except RateLimitError:
    # Queue for later or use backup
    add_to_queue(request)
except APIError as e:
    if e.status_code == 402:
        notify_admin("Balance low")
    elif e.status_code >= 500:
        # Server error, retry later
        schedule_retry(request)
```

### 10. 使用回退模型

```python theme={null}
FALLBACK_CHAIN = ["gpt-4o", "claude-sonnet-4-6", "gemini-3.5-flash"]

def chat_with_fallback(messages):
    for model in FALLBACK_CHAIN:
        try:
            return client.chat.completions.create(
                model=model,
                messages=messages
            )
        except APIError:
            continue
    raise Exception("All models failed")
```

## 安全性

### 11. 保护 API Key

```python theme={null}
# ❌ Never hardcode keys
client = OpenAI(api_key="sk-abc123...")

# ✅ Use environment variables
import os
client = OpenAI(api_key=os.environ["TOKENLAB_API_KEY"])
```

### 12. 验证用户输入

```python theme={null}
def validate_message(content: str) -> bool:
    """Validate user input before sending to API."""
    if len(content) > 100000:
        raise ValueError("Message too long")
    # Add other validation as needed
    return True
```

### 13. 设置 API Key 限额

为以下场景创建带有消费限额的独立 API Key：

* 开发/测试
* 生产环境
* 不同应用程序

## 监控

### 14. 跟踪使用情况

定期检查你的仪表盘，关注：

* 按模型统计的 token 使用量
* 成本明细
* 缓存命中率
* 错误率

### 15. 记录重要指标

```python theme={null}
import logging

response = client.chat.completions.create(...)

logging.info({
    "model": response.model,
    "prompt_tokens": response.usage.prompt_tokens,
    "completion_tokens": response.usage.completion_tokens,
    "total_tokens": response.usage.total_tokens,
})
```

### 16. 设置告警

在你的仪表盘中配置低余额告警，以避免服务中断。

## 检查清单

<AccordionGroup>
  <Accordion title="成本优化">
    * [ ] 为每项任务使用合适的模型
    * [ ] 设置 max\_tokens 限制
    * [ ] Prompt 简洁
    * [ ] 在适用场景启用缓存
    * [ ] 批量处理相似请求
  </Accordion>

  <Accordion title="性能">
    * [ ] 为交互式 UX 使用流式输出
    * [ ] 为实时使用选择快速模型
    * [ ] 已配置超时
  </Accordion>

  <Accordion title="可靠性">
    * [ ] 已实现重试逻辑
    * [ ] 已具备错误处理机制
    * [ ] 已配置回退模型
  </Accordion>

  <Accordion title="安全性">
    * [ ] API Key 存储在环境变量中
    * [ ] 输入验证
    * [ ] 为 dev/prod 使用独立 Key
    * [ ] 已设置消费限额
  </Accordion>
</AccordionGroup>
