Chat API

{
  "messages": [
    {
      "role": "system",
      "content": "You are a creative content writer specializing in blog posts."
    },
    {
      "role": "user", 
      "content": "Write an introduction for a blog post about sustainable living tips."
    }
  ]
}

{
  "messages": [
    {
      "role": "system",
      "content": "You are a professional email writer. Write clear, polite, and effective emails."
    },
    {
      "role": "user",
      "content": "Write a follow-up email for a job interview."
    }
  ]
}

{
  "messages": [
    {
      "role": "system",
      "content": "You are an expert copywriter. Write compelling marketing copy that drives action."
    },
    {
      "role": "user",
      "content": "Create homepage copy for a productivity app targeting busy professionals."
    }
  ]
}

{
  "messages": [
    {
      "role": "system",
      "content": "You are a helpful programming assistant. Provide clean, well-documented code."
    },
    {
      "role": "user",
      "content": "Write a Python function to calculate the fibonacci sequence."
    }
  ]
}

{
  "messages": [
    {
      "role": "system",
      "content": "You are a senior software engineer. Provide constructive code reviews."
    },
    {
      "role": "user",
      "content": "Review this JavaScript function and suggest improvements: [code here]"
    }
  ]
}

{
  "messages": [
    {
      "role": "system",
      "content": "You are a debugging expert. Help identify and fix code issues."
    },
    {
      "role": "user",
      "content": "I'm getting a TypeError in this Python code. Can you help me fix it?"
    }
  ]
}

{
  "error": "Invalid API key"
}

{
  "error": "Messages array is required"
}

{
  "error": "Last message must have valid content"
}

{
  "error": "Token limit exceeded"
}

{
  "error": "Rate limit exceeded"
}

{
  "error": "Failed to generate response"
}

// ✅ Good - Handle streaming for real-time display
const processStreamingResponse = async (response) => {
  const reader = response.body.getReader();
  const decoder = new TextDecoder();
  
  while (true) {
    const { done, value } = await reader.read();
    if (done) break;
    
    const chunk = decoder.decode(value);
    displayChunk(chunk); // Update UI immediately
  }
};

// ✅ Good - Robust error handling
const makeRequest = async (messages, retries = 3) => {
  for (let i = 0; i < retries; i++) {
    try {
      const response = await fetch('/api/v1/chat', {
        method: 'POST',
        headers: {
          'Authorization': `Bearer ${apiKey}`,
          'Content-Type': 'application/json'
        },
        body: JSON.stringify({ messages })
      });
      
      if (!response.ok) {
        const error = await response.json();
        throw new Error(error.error);
      }
      
      return response;
    } catch (error) {
      if (i === retries - 1) throw error;
      await new Promise(resolve => setTimeout(resolve, 1000 * Math.pow(2, i)));
    }
  }
};

// ✅ Good - Track usage
const estimateTokens = (text) => Math.ceil(text.length / 4);

const makeRequestWithTracking = async (messages) => {
  const inputTokens = messages.reduce((sum, msg) => sum + estimateTokens(msg.content), 0);
  console.log(`Estimated input tokens: ${inputTokens}`);
  
  // Make request and track output tokens
  const response = await makeRequest(messages);
  const output = await readStreamingResponse(response);
  const outputTokens = estimateTokens(output);
  
  console.log(`Total tokens used: ${inputTokens + outputTokens}`);
  return output;
};