#13 — ChatGPT 4 prompt engineering for founders

Why it matters: GPT-4 offers startup founders powerful capabilities for building AI-powered products, with recent updates dramatically expanding what's possible through effective prompt engineering.§

By the numbers:§

• GPT-4 scores in the top 10% on simulated bar exams
• Context window of 128K tokens (equivalent to 300+ pages)
• Training data cutoff: April 2023

Key capabilities for founders

GPT-4 Turbo: The latest iteration brings improved instruction following, JSON mode, reproducible outputs, and parallel function calling - critical features for product integration.§

Vision integration: The model now processes images alongside text, enabling applications from chart analysis to visual content moderation.§

JSON structuring: Founders can force structured outputs by setting response_format to { type: "json_object" }, making API integration significantly easier.§

Engineering best practices

Steering tone and style: System messages allow founders to define product voice once rather than in every prompt:§

from openai import OpenAI
client = OpenAI()
response = client.chat.completions.create(
  model="gpt-4-1106-preview",
  messages=[
    {"role": "system", "content": "You are a helpful assistant."},
    {"role": "user", "content": "Who won the world series in 2020?"}
  ]
)

Function calling: Define functions and let GPT-4 intelligently generate JSON for function calls - perfect for converting natural language into API calls or extracting structured data.§

Reproducibility: Set the seed parameter to any integer for deterministic outputs, critical for testing and debugging AI features.§

The bottom line

GPT-4 excels at drafting documents, writing code, answering questions, and creating natural language interfaces - but founders should implement safeguards against hallucinations and reasoning errors, especially for high-stakes applications.§

Go deeper: Combine GPT-4 with external knowledge sources and advanced prompt techniques like chain-of-thought prompting to maximize reliability.§