Build a believable character with AI in six steps

AI can help you test a character, but the character must come from you. Use these steps with a chat tool such as ChatGPT or Claude, or inside a writing app such as Novelcrafter Codex or Sudowrite Story Bible characters.

1. Start with the core

Write four lines. What does this person want most? What do they fear? What false belief do they hold about the world or themselves? What contradiction makes them surprising, such as a kind person who lies well? Ask the AI to find gaps or clashes in these four lines. Do not ask it to fill them in.

2. Give them a backstory of cause and effect

Each past event should explain something they do now. If an event changes nothing, cut it. Avoid pain added just for shock. Ask the AI: "Which of these past events does not explain anything in the present?"

3. Work out behaviour and voice

How do they talk when calm, and when scared? What do they do with their hands? What words would they never use? Write a short sample of their speech, then ask the AI where it slips out of character.

4. Stress test them in scenes

Put the character in three hard spots that are not in your book, such as a rude stranger, a lost job or a secret found out. Ask the AI how they might react, then ask which reaction fits the core from step 1. In Novelcrafter you can interview the character directly.

5. Plan the arc

How does the false belief change by the end? Note the moments that push on it. Ask the AI if each push is strong enough to make the change believable.

6. Keep a living character bible

Keep one file per character with two parts: settled facts, such as eye colour and age, and ideas you are still trying. Move an idea to settled facts only when it is on the page. Tools such as Campfire Writing help map family trees and links between characters.

Next: See your characters with AI in five steps. All character tools: Characters.