This path takes you from an AI app with no access to Fantasma to a theme live on your Ghost site. You write what you want in the chat, the agent builds it in a Fantasma project, and you check the result in the builder. The agent is the assistant in your AI app, such as Claude or ChatGPT. Building is free. Publishing, downloading and restoring versions need Pro.
1. Connect your AI app
Follow Connect an AI agent for Claude, ChatGPT, Codex, Cursor or another app. On Fantasma's consent page, keep Build checked, so the agent can create and edit projects. Leave Publish unchecked until you want to publish, so the agent cannot change your live site by mistake.
Then ask the agent "List my Fantasma projects." It answers with the names on your Fantasma dashboard, or says you have none yet. In Fantasma, your app now shows under Account settings › Connected apps.
2. Ask for a new project
Before it designs, Fantasma tells the agent to ask about your publication: what it publishes, who reads it, what a first visit should lead to, and colors or fonts to keep. It suggests an answer for each, and writes what you agree to into the project's DESIGN.md, which you can edit later in Agent instructions.
Describe the site in a few sentences, and give the project a name, so you and the agent can refer to it later. For example:
Create a Fantasma project named Copper Kettle for a coffee blog. Give the Homepage a large heading, the latest posts in a grid, and a newsletter signup. Use warm colors and a serif font for headings.
The agent creates the project and builds its templates from Fantasma's sections, blocks and patterns. A template is the design of one kind of Ghost page, such as the Homepage or the Post template every post uses. The new project appears on your Fantasma dashboard.
On Free, you can have 3 active projects. If you already have 3, the agent cannot create another, and neither can you, until you move one to the trash.
3. Look at the result in Fantasma
On the Fantasma dashboard, click the project. It opens in the builder, and the canvas in the middle shows the templates the agent built. Until you connect your Ghost site in step 5, the canvas fills them with Fantasma's demo posts.
Keep the builder open while you go on. When the agent changes the project again, switch back to the builder's browser tab, and it shows the new version.
4. Change the design
Ask for one change at a time, and name the project, the template and the section, because the agent cannot see what you selected on the canvas. For example:
In Copper Kettle, on the Post template, add the reading time under the post title.
In Copper Kettle, give the newsletter section on the Homepage a dark color scheme.
Check each change in the builder before you ask for the next one. You can also change anything yourself. If you edit in the builder while the agent changes the project, Fantasma saves your edits as a backup and asks you to reload, as "This project was changed in another window" explains.
In the builder, connect your Ghost site to the project in Project settings › Ghost. That article shows which key to copy from Ghost Admin. Connecting it yourself keeps the key out of the chat.
In Account settings › Connected apps, check Publish for your app.
Click Save changes.
In the chat, ask the agent to publish, such as "Publish Copper Kettle to my Ghost site."
Read the agent's question. It names the project and the site. If either is wrong, answer no.
Answer yes. The agent uploads the theme to Ghost, makes it the active theme, and reports the result.
Your Ghost site now shows the new design. The theme it used before stays installed in Ghost Admin, so you can switch back there. Later changes reach your site only when you publish again. To publish without the agent, click Publish at the top of the builder's right sidebar, as Publish your theme to Ghost shows. If publishing fails, Publishing to Ghost failed lists the causes.
This path takes you from an AI app with no access to Fantasma to a theme live on your Ghost site. You write what you want in the chat, the agent builds it in a Fantasma project, and you check the result in the builder. The agent is the assistant in your AI app, such as Claude or ChatGPT. Building is free. Publishing, downloading and restoring versions need Pro.
1. Connect your AI app
Follow Connect an AI agent for Claude, ChatGPT, Codex, Cursor or another app. On Fantasma's consent page, keep Build checked, so the agent can create and edit projects. Leave Publish unchecked until you want to publish, so the agent cannot change your live site by mistake.
Then ask the agent "List my Fantasma projects." It answers with the names on your Fantasma dashboard, or says you have none yet. In Fantasma, your app now shows under Account settings › Connected apps.
2. Ask for a new project
Before it designs, Fantasma tells the agent to ask about your publication: what it publishes, who reads it, what a first visit should lead to, and colors or fonts to keep. It suggests an answer for each, and writes what you agree to into the project's
DESIGN.md, which you can edit later in Agent instructions.Describe the site in a few sentences, and give the project a name, so you and the agent can refer to it later. For example:
The agent creates the project and builds its templates from Fantasma's sections, blocks and patterns. A template is the design of one kind of Ghost page, such as the Homepage or the Post template every post uses. The new project appears on your Fantasma dashboard.
On Free, you can have 3 active projects. If you already have 3, the agent cannot create another, and neither can you, until you move one to the trash.
3. Look at the result in Fantasma
On the Fantasma dashboard, click the project. It opens in the builder, and the canvas in the middle shows the templates the agent built. Until you connect your Ghost site in step 5, the canvas fills them with Fantasma's demo posts.
Keep the builder open while you go on. When the agent changes the project again, switch back to the builder's browser tab, and it shows the new version.
4. Change the design
Ask for one change at a time, and name the project, the template and the section, because the agent cannot see what you selected on the canvas. For example:
Check each change in the builder before you ask for the next one. You can also change anything yourself. If you edit in the builder while the agent changes the project, Fantasma saves your edits as a backup and asks you to reload, as "This project was changed in another window" explains.
To undo what the agent did, ask it to change it back, or on Pro restore an earlier version.
5. Publish to Ghost
This part needs Pro.
Your Ghost site now shows the new design. The theme it used before stays installed in Ghost Admin, so you can switch back there. Later changes reach your site only when you publish again. To publish without the agent, click Publish at the top of the builder's right sidebar, as Publish your theme to Ghost shows. If publishing fails, Publishing to Ghost failed lists the causes.
What an AI agent can do in Fantasma lists everything else an agent can do, and what it asks you first.