How to beginner · 3 min read

How to use AI to write technical documentation

Quick answer
Use AI models like gpt-4o to generate technical documentation by providing clear prompts describing the software or API features. Call the chat.completions.create endpoint with structured messages to get well-organized, human-readable docs 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 to authenticate requests.

bash
pip install openai>=1.0

Step by step

Use the OpenAI gpt-4o model to generate technical documentation by sending a prompt that describes the software or API. The model will return structured, clear documentation text.

python
import os
from openai import OpenAI

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

prompt = (
    "Write detailed technical documentation for a Python library that provides functions to "
    "connect to a database, execute queries, and handle errors. Include usage examples."
)

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

print(response.choices[0].message.content)
output
'''Example output:
# Database Connector Library

This Python library provides functions to connect to a database, execute SQL queries, and handle errors gracefully.

## Features
- Connect to various databases using connection strings
- Execute SELECT, INSERT, UPDATE, DELETE queries
- Automatic error handling with descriptive exceptions

## Usage Example
```python
from db_connector import connect, execute_query

conn = connect("postgresql://user:pass@localhost/dbname")
result = execute_query(conn, "SELECT * FROM users")
print(result)
```
'''

Common variations

You can customize the documentation style by changing the prompt or use different models like claude-3-5-sonnet-20241022 for more creative outputs. Async calls and streaming completions are also supported for large docs.

python
import os
from openai import OpenAI

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

async def generate_doc_async():
    response = await client.chat.completions.acreate(
        model="gpt-4o",
        messages=[{"role": "user", "content": "Write API docs for a REST client library."}]
    )
    print(response.choices[0].message.content)

# For streaming (simplified example):
response = client.chat.completions.create(
    model="gpt-4o",
    messages=[{"role": "user", "content": "Document a CLI tool."}],
    stream=True
)
for chunk in response:
    print(chunk.choices[0].delta.get('content', ''), end='')

Troubleshooting

  • If the output is too generic, provide more detailed prompts with specific features or examples.
  • If you get rate limit errors, check your API usage and consider retrying after a delay.
  • For incomplete responses, increase max_tokens or use streaming to receive the full content.

Key Takeaways

  • Use clear, detailed prompts to guide AI in generating precise technical documentation.
  • Leverage gpt-4o or claude-3-5-sonnet-20241022 for high-quality, structured docs.
  • Async and streaming API calls help handle large or complex documentation generation.
  • Always set your API key securely via environment variables for authentication.
  • Adjust max_tokens and prompt specificity to improve output completeness and relevance.
Verified 2026-04 · gpt-4o, claude-3-5-sonnet-20241022
Verify ↗