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OpenAI's ChatGPT Prompt Engineering: How to Get Started

2026-09-19 · 5 min read · SubToAPI Team

If you're searching for "how to get ChatGPT prompt engineering from OpenAI," you want two things: where OpenAI actually publishes its guidance, and what that guidance says you should do differently in your prompts. The short answer is that OpenAI doesn't sell a prompt engineering course — it publishes a free guide in its API documentation, and the techniques in it are the same ones that show up in every serious guide to working with large language models.

This article walks through where to find that material, what it actually recommends, and how to turn those recommendations into prompts and API calls you can ship.

Where OpenAI publishes its prompt engineering guidance

OpenAI's official prompt engineering material lives inside the API platform documentation, under the "Guides" section, specifically the prompt engineering guide. It's not a paid product — it's a reference page aimed at developers building on the API, and it gets updated as OpenAI's models and best practices change.

A few things worth knowing before you go looking for it:

If you're using ChatGPT through the consumer app rather than the API, the same principles apply — you just don't have access to parameters like system messages or temperature in the same way.

The core techniques OpenAI recommends

Strip out the branding and OpenAI's guidance boils down to a handful of concrete moves:

Write clear, specific instructions. Vague prompts get vague answers. Instead of "summarize this," specify length, tone, audience, and format: "Summarize this in three bullet points for a non-technical manager."

Give the model a persona or role. Framing the task ("You are a senior backend engineer reviewing a pull request") narrows the range of plausible responses and improves consistency.

Use system messages to set behavior. The system message is where you put standing instructions — tone, constraints, output format — separate from the per-request user message. This keeps your prompts modular and easier to test.

Provide examples (few-shot prompting). Showing the model one or two examples of the input/output pattern you want is often more reliable than describing the pattern in words.

Break complex tasks into steps. Instead of asking for a finished report in one shot, ask the model to first outline, then draft, then revise. This mirrors how you'd manage a junior team member.

Give the model room to "think." Asking for reasoning before the final answer, or asking it to check its own output, reduces careless errors on tasks that involve logic or arithmetic.

Reduce hallucination with grounding. Provide the actual source text, document, or data in the prompt rather than relying on the model's memory of facts.

None of this is exotic. What separates a working prompt from a fragile one is usually specificity, structure, and testing — not a secret technique.

Turning guidance into a repeatable prompt

Here's a minimal example of applying system message separation and few-shot examples in an API call:

const response = await fetch("https://api.openai.com/v1/chat/completions", {
  method: "POST",
  headers: {
    "Authorization": `Bearer ${process.env.OPENAI_API_KEY}`,
    "Content-Type": "application/json"
  },
  body: JSON.stringify({
    model: "gpt-4o",
    messages: [
      {
        role: "system",
        content: "You are a support ticket classifier. Respond with only one label: billing, technical, or account."
      },
      { role: "user", content: "I was charged twice for my subscription this month." },
      { role: "assistant", content: "billing" },
      { role: "user", content: "My login keeps failing even after I reset my password." }
    ]
  })
});

The pattern — system message for role and constraints, a couple of labeled examples, then the real input — is exactly what OpenAI's guide recommends, and it works the same way regardless of which model is answering.

The same techniques apply beyond ChatGPT

This is worth calling out because it changes how you should think about "learning prompt engineering for OpenAI" versus learning it in general: none of the techniques above are OpenAI-specific. Clear instructions, system-level constraints, few-shot examples, and step-by-step decomposition improve output quality on Claude, Gemini, or any other instruction-tuned model. The vocabulary differs slightly (system message vs. system prompt, temperature vs. sampling settings), but the underlying discipline is the same.

If your team is already comfortable prompting ChatGPT and wants to run the same workflows against Claude — for a second opinion, a cost comparison, or because Claude handles a particular task better — you don't need to relearn prompt engineering from scratch. SubToAPI turns your existing Claude access into a standard HTTPS API with sub_live_... application keys, so you can reuse the same message structure, system prompts, and few-shot patterns you'd use with OpenAI's API. Check the quickstart or the messages reference to see how closely the request shape maps to what you're already doing.

curl https://api.subtoapi.app/v1/messages \
  -H "Authorization: Bearer $SUBTOAPI_KEY" \
  -H "Content-Type: application/json" \
  -d '{
    "model": "claude-sonnet-4",
    "system": "You are a support ticket classifier. Respond with only one label: billing, technical, or account.",
    "messages": [
      {"role": "user", "content": "My login keeps failing even after I reset my password."}
    ]
  }'

If you want to test that side by side with your OpenAI prompts, sign up for a free trial and compare outputs before committing to a plan — pricing starts at €9/month, listed on the pricing page.

Practical next steps

  1. Read OpenAI's prompt engineering guide once, end to end — it's short.
  2. Take one real prompt you use regularly and rewrite it with a system message, an explicit format requirement, and one example.
  3. Test the before/after on 5–10 real inputs, not one cherry-picked example.
  4. If the task involves multiple steps, split it into separate calls instead of one giant prompt.
  5. Keep a small library of prompts that worked, with notes on why — this becomes your team's actual prompt engineering reference over time.

FAQs

Does OpenAI offer a paid prompt engineering course? No. OpenAI's official guidance is a free page in its API documentation. Paid "OpenAI prompt engineering certifications" you may find elsewhere are third-party products, not official OpenAI offerings.

Can I use OpenAI's prompt engineering techniques with other AI models? Yes. Techniques like system messages, few-shot examples, and step-by-step decomposition are model-agnostic and work with Claude, Gemini, and other instruction-tuned LLMs with minor syntax differences.

What's the fastest way to improve my ChatGPT prompts? Add explicit constraints (length, format, audience) and one or two examples of the output you want. Vague, open-ended prompts are the single biggest cause of inconsistent results.

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