We have just added five new AI models to NovelistAI: three for writing and two for covers. They are live now, and they work exactly like the models you already use. Open a new book, choose one in the AI Model step, and start writing. Each one shows a "New!" badge in the picker, so they are easy to spot.
Every model writes a little differently. That is the point of having several: when a chapter is not landing the way you imagined, the same instructions on a different model often give you exactly the page you were looking for.
Three New Writing Models
GPT-6.1 Terra is OpenAI's newest generation, and it comes with a one-million-token context window. For a writer, a big context window means the model can keep much more of your book in view while it drafts. A side character from chapter three is still the same person in chapter thirty, a promise made early in the plot is still remembered near the end, and the voice you set on page one carries through. GPT-6.1 Terra costs 2 credits per page, half the price of GPT-6 Sol, and it is available on Premium plans.
Claude Haiku 5.5 is the fast tier of Anthropic's Claude family. It brings Sonnet-family prose at the lowest price in our catalogue: 1 credit per page, available to everyone, including the free plan. If you have never tried a Claude model, Haiku 5.5 is an easy way to hear what it sounds like.
Gemini 4 Argon is Google's Gemini 4 generation, also with a one-million-token context window. Reasoning is always on, which means the model thinks a story through before it writes the page. That makes it a strong choice for books where the logic has to hold together: mysteries with clues to plant, gamebooks with choices that branch and come back together, or non-fiction where one chapter builds on the last. Gemini 4 Argon costs 4 credits per page and is available on Premium plans.
Two New Cover Models
Ideogram V4.5 is the strongest of our image models at rendering a title. Text on a generated cover has always been the tricky part: letters melt, words get misspelled, the author name drifts off the edge. Ideogram V4.5 is built for exactly this, so it is the model to reach for when you want the title and your name on the cover itself, not added afterwards. It costs 5 credits per image and is available to everyone.
Flux 3 is the newest image model from Black Forest Labs, and the cheapest way to try a cover idea. Use it when the picture matters more than the lettering: a mood, a landscape, a character portrait for a fantasy or romance cover. It costs 3 credits per image and is available to everyone.
Create a Cover or Edit the One You Have
Both new cover models work in both modes of the Image Studio. Use Generate to create a cover from a description of your book. Use Edit Image to refine one you already have: pick an image from your gallery or upload your own, describe the change in plain language, and the model changes only that part.
That makes small fixes simple. Change the colour of a dress, remove an object from the background, or replace the title text after you rename your book, and the rest of the cover stays as it was. You do not have to regenerate the whole image and hope the parts you liked survive.
Which Model Should You Pick?
Here is a simple way to choose, depending on what you are doing.
Drafting a full book. Start with Claude Haiku 5.5 if you want the most pages for your credits; at 1 credit per page it is the cheapest way to write a complete first draft, and it is available on every plan. On a Premium plan, GPT-6.1 Terra at 2 credits per page is the best value for long novels, because its large context window keeps characters and plot threads consistent across many chapters.
Complex plots and gamebooks. Choose Gemini 4 Argon when the structure matters as much as the prose: a whodunit, a branching gamebook, a series with lots of world-building, or a non-fiction book with a clear argument. It costs more per page, so many writers use it for the chapters where the plot turns, and a cheaper model for the rest.
Rewriting and editing pages. Every page in the editor can be rewritten or edited with AI (shorten, extend, change the tone). If a page feels flat, try rewriting it with a different model before you change your instructions. A Claude page and a GPT page from the same prompt can feel surprisingly different, and switching is free apart from the usual page credits.
Covers with a title. Use Ideogram V4.5 when the cover needs readable text: the title, a subtitle, your author name.
Covers and illustrations without text. Use Flux 3 when you want an image-first cover or an illustration, then add or fix details with Edit Image.
You can change models at any time, even halfway through a book. Credit costs are shown next to every model in the picker, so you always know what a page or an image will cost before you generate it.
Also in the Picker
The new models join the ones you already know, including GPT-6 Luna, GPT-6 Sol, GPT-5.6 Terra and Luna, Claude Sonnet 5 and 5.5, Gemini 3.8 Flash and the Grok family.
Try Them Today
Open a book on NovelistAI, pick one of the new models in the AI Model step, and write your next page. The free plan includes 10 credits a month, which is enough to try Claude Haiku 5.5 on a few pages and see how it sounds for your story.
