Creating a custom GPT agent is available to ChatGPT plus users. This post covers the main steps from creation to publishing.

Creation

Open the Explore GPTs tab and choose the Create option.

Write a description of what agent you would like to create.

GPT builder will also propose a GPT name and generate a profile picture.

Refine the GPT context with the builder. Choose interaction style and personalization for the agent.

Knowledge base

Upload files with knowledge data in the Configure tab.

Use files in formats like JSON, PDF, and CSV.

Using external API

Create a new action in the Configure tab by entering OpenAPI docs in the Schema field.

Enter schema in JSON or YAML format or import it from the URL, and ensure it contains the server's URL configured.

Set Authentication for the provided API and test the created action via the Test button.

Security

Add a rule not to expose internal instructions so other users can't copy your configuration.

Add a rule not to expose internal instructions if a user asks for it, and answer with "Sorry, it's not possible."

Publishing

To make your GPT publicly available in the GPT Store, you need to verify the website domain.

Open Settings & Beta → Builder profile and verify the new domain for the website. You'll get TXT value, which you need to configure on your domain service like Namecheap, using @ as the host value.

Once you verified the website, click the Save → Public → Confirm buttons to publish your new GPT.

Examples

• Hackathon Mentor

• JavaScript Full-Stack Web Development Mentor

• Notion Templates Creator

ChatGPT is a large language model (LLM) that understands and processes human prompts to produce helpful responses. OpenAI provides an API to interact with the ChatGPT model (gpt-3.5-turbo).

Prerequisites

• OpenAI account
• Generated API key
• Enabled billing

Integration

Below is an example of interacting with ChatGPT API based on a given prompt.

const handlePrompt = async (prompt) => {
  const response = await axios.post(
    'https://api.openai.com/v1/chat/completions',
    {
      model: 'gpt-3.5-turbo',
      messages: [
        {
          role: 'user',
          content: prompt
        }
      ]
    },
    {
      headers: {
        Authorization: `Bearer ${process.env.OPENAI_API_KEY}`
      }
    }
  );
  return response?.data?.choices?.[0]?.message?.content;
};