使用 ChatCompletions API 產生回應

已完成

OpenAI ChatCompletions API 廣泛應用於生成式 AI 模型與平台。 雖然 Responses API 建議用於新專案開發，但你很可能會遇到 ChatCompletions API 對跨平台相容程式碼維護非常有用的情況。

提交提示

ChatCompletions API 使用以 JSON 格式封裝訊息物件的集合來封裝提示：

completion = openai_client.chat.completions.create(
    model="gpt-4o",  # Your model deployment name
    messages=[
        {"role": "system", "content": "You are a helpful assistant."},
        {"role": "user", "content": "When was Microsoft founded?"}
    ]
)

print(completion.choices[0].message.content)

保留會話語境

與 回應 API 不同， ChatCompletins API 不提供有狀態的回應追蹤功能。 為了保留對話上下文，你必須撰寫程式碼手動追蹤先前的提示與回應。

# Initial messages
conversation_messages=[
    {
        "role": "system",
        "content": "You are a helpful AI assistant that answers questions and provides information."
    }
]

# Add the first user message
conversation_messages.append(
    {"role": "user",
    "content": "When was Microsoft founded?"}
)

# Get a completion
completion = openai_client.chat.completions.create(
    model="gpt-4o",
    messages=conversation_messages
)
assistant_message = completion.choices[0].message.content
print("Assistant:", assistant_text)

# Append the response to the conversation
conversation_messages.append(
    {"role": "assistant", "content": assistant_text}
)

# Add the next user message
conversation_messages.append(
    {"role": "user",
    "content": "Who founded it?"}
)

# Get a completion
completion = openai_client.chat.completions.create(
    model="gpt-4o",
    messages=conversation_messages
)
assistant_message = completion.choices[0].message.content
print("Assistant:", assistant_text)

# and so on...

在實際應用中，對話通常以迴圈形式實作;像這樣：

# Initial messages
conversation_messages=[
    {
        "role": "system",
        "content": "You are a helpful AI assistant that answers questions and provides information."
    }
]

# Loop until the user wants to quit
print("Assistant: Enter a prompt (or type 'quit' to exit)")
while True:
    input_text = input('\nYou: ')
    if input_text.lower() == "quit":
        print("Assistant: Goodbye!")
        break

    # Add the user message
    conversation_messages.append(
        {"role": "user",
        "content": input_text}
    )

    # Get a completion
    completion = openai_client.chat.completions.create(
        model="gpt-4o",
        messages=conversation_messages
    )
    assistant_message = completion.choices[0].message.content
    print("\nAssistant:", assistant_message)
    
    # Append the response to the conversation
    conversation_messages.append(
        {"role": "assistant", "content": assistant_message}
    )

這個範例的輸出看起來類似：

Assistant: Enter a prompt (or type 'quit' to exit)

You: When was Microsoft founded?

Assistant: Microsoft was founded on April 4, 1975 in Albuquerque, New Mexico, USA.

You: Who founded it?

Assistant: Microsoft was founded by Bill Gates and Paul Allen.

You: quit

Assistant: Goodbye!

每個新使用者提示和完成都會新增至交談，然後每輪都會將完整的交談歷程記錄提交到系統。

雖然功能不如 回應 API 完整，但 ChatCompletions API 在生成式 AI 模型生態系中已相當成熟，熟悉它會很有幫助。