How to beginner · 3 min read

How to use AI for email writing

Q: How to use AI for email writing

Use the gpt-4o model from OpenAI's API to generate email drafts by providing prompts describing the email's purpose. Call client.chat.completions.create with your prompt to receive polished email text automatically.

Quick answer

Use the gpt-4o model from OpenAI's API to generate email drafts by providing prompts describing the email's purpose. Call client.chat.completions.create with your prompt to receive polished email text automatically.

PREREQUISITES

Python 3.8+
OpenAI API key (free tier works)
pip install openai>=1.0

Setup

Install the OpenAI Python SDK and set your API key as an environment variable for secure access.

bash

pip install openai>=1.0

Step by step

This example shows how to generate a professional email draft using the gpt-4o model with the OpenAI Python SDK v1.

python

import os
from openai import OpenAI

client = OpenAI(api_key=os.environ["OPENAI_API_KEY"])

prompt = "Write a professional email to schedule a meeting with a client next week."

response = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": prompt}]
)

email_text = response.choices[0].message.content
print(email_text)

output

Subject: Meeting Scheduling for Next Week

Dear [Client's Name],

I hope this message finds you well. I would like to schedule a meeting with you next week to discuss our ongoing projects and next steps. Please let me know your availability so we can arrange a convenient time.

Looking forward to your response.

Best regards,
[Your Name]

Common variations

You can customize the email style by changing the prompt or use different models like gpt-4o-mini for faster responses. Async calls and streaming completions are also supported for advanced use cases.

python

import asyncio
import os
from openai import OpenAI

async def generate_email():
    client = OpenAI(api_key=os.environ["OPENAI_API_KEY"])
    prompt = "Write a friendly follow-up email after a job interview."

    response = await client.chat.completions.acreate(
        model="gpt-4o-mini",
        messages=[{"role": "user", "content": prompt}]
    )

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

asyncio.run(generate_email())

output

Subject: Following Up on Our Interview

Hi [Interviewer’s Name],

Thank you again for the opportunity to interview for the [Job Title] position. I enjoyed learning more about the team and the role. Please let me know if you need any additional information from me.

Looking forward to hearing from you.

Best,
[Your Name]

Troubleshooting

If you get authentication errors, verify your OPENAI_API_KEY environment variable is set correctly.
If responses are incomplete, increase max_tokens in the API call.
For rate limit errors, implement exponential backoff retries.

✅

Key Takeaways

Use gpt-4o with OpenAI SDK v1 for reliable email generation.
Customize prompts to tailor email tone and content precisely.
Set OPENAI_API_KEY securely in your environment variables.
Async and smaller models like gpt-4o-mini offer flexible performance options.
Handle API errors by checking keys, token limits, and rate limits.

Verified 2026-04 · gpt-4o, gpt-4o-mini

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