Getting Started

The Dashboard page is the starting point: see your novels and create new ones. Account-level settings — your LLM provider and your rewrite prompts — live in the Configuration and Prompts menus in the top navigation.

Setting Up Your LLM Provider

If you want AI-powered continuations and chapter summaries, then you'll need to configure your preferred LLM provider:

1. Open the Configuration menu in the top navigation and choose LLM
2. Select your preferred provider (OpenAI, Anthropic, or OpenRouter.ai)
3. Enter your API key for the selected provider
4. Choose your preferred model from the available options

My personal preference is OpenRouter.ai because it's easy to set up an API key, choose from a greater range of models, and see all of your costs broken down by app and time. But to use the premium models we enable in Prosie, you'll need to add payment information and buy credits. The same goes with OpenAI and Anthropic, though their setup process is a little more involved.

If you're concerned about costs, then start small and keep your context (lore, characters, etc.) lean. The Anthropic models (e.g. Claude 3.7 Sonnet) tend to be the most expensive, so try experimenting with different models. I've added some "mini" models and cheaper alternatives for this reason. Remember: there is no need to actually use AI in Prosie. It works fine as a novel writing tool by itself, and using AI sparingly will improve your prose style and your voice and ensure any AI assistance you do use in Prosie will be much more like your own prose.

Note: Prosie is free to use, but requires your own API key. You are responsible for any usage costs from your chosen LLM provider.

Creating Your First Book

Once your LLM provider is configured, you can create your first book:

1. Click the + New Book button in the Your Books box (or pick + New Book from the Series menu) to open the create page
2. Enter a title for your book (don't worry, you can change it later)
3. Select your preferred point-of-view (first person, third person, etc.)
4. Choose the tense for your narrative (past or present)
5. Click "Create" and you'll be taken to the book's Edit page
6. Here you can add context about your book's lore and characters

Tip: Be as specific as possible when adding details about your story's intended prose style, lore, and characters. Without this context, your LLM provider might invent things you didn't intend or miss things important to your story. There's no single correct way. In fact, the more you experiment and find a unique set of inputs that work for you, the better your results will be.

The Writing Environment

After creating a book (or selecting an existing one from "Your Books" list), you'll enter the writing environment by clicking the "Write" button.

Writing and Editing

The writing space provides a clean, distraction-free environment where you can:

• Write your content freely in a rich text editor
• Format text with bold and italic styling
• Edit the chapter name by clicking on it
• Change the chapter order in your book
• Track your word count through the "More" menu

AI-Powered Continuations

When you're stuck or want assistance, hit the "Continue ✨" button:

1. Write some beat instructions in the popup modal to establish context for the AI
2. Click the "Continue ✨" button when you want the AI to generate a continuation
3. We'll construct a system prompt that includes your book details and a role instructon we've found works best.
4. We also construct a multi-turn "few-shot" prompt that uses the current chapter's text as the AI's "own" text and asks it to continue it.
5. We'll then send this complete prompt to your AI provider and model of choice, using the API token you provided us with, and then add the resulting response to your chapter.
6. The generated text appears in your writing space, where you can edit it as needed

Note: Prosie previously offered a second prompting strategy — listed as "Prefill / Continuation" in your LLM settings — which used Anthropic's prefill feature to have the model continue your chapter text directly. We've removed it (along with the strategy selector) because prefill no longer works reliably on Claude 4.6+ models or Mythos — those models start a fresh response instead of continuing the prefilled text. All continuations now use the multi-turn strategy described above, which is what "Auto" already did for most providers.

Chapters, the Codex & Context

Chapter summaries, the mention-aware Codex, and shared Series worlds are how Prosie feeds the AI the right context without dumping your whole world bible on every request. They have their own page: Chapters, the Codex & Context →

The Prosie API (for power users)

Prosie exposes a token-authenticated HTTP API so you can drive your stories from your own tools — a backup script, an Obsidian plugin, an iOS Shortcut, a Discord bot, or a keyboard macro — carrying the same voice-preserving context as the editor. See the full reference: The Prosie API →

Tips for Better Results

• Be detailed with book information: The more information you provide in your book's character and lore sections, the better the AI can maintain narrative consistency.
• Use beat instructions in Continue requests: For best results, be specific about what you want to happen next, and tell the AI when you want it to stop.
• Update chapter summaries regularly: Keep your chapter summaries current for the best AI continuations.
• Edit generated content: Always review and edit AI-generated text to match your voice and style. If you keep using the Continue feature without editing or writing any of the content yourself, the AI will diverge away from your intended style.
• Never paste copyrighted content: Don't use other authors' writing as a basis for AI continuations. This crosses many ethical lines and will cause deviations in the AI's prose style from your own.
• Be careful with NSFW content: I don't personally write in genres with NSFW content, so I haven't tested Prosie with that kind of writing. Per the Terms, you're responsible for any consequences as a result of sending NSFW content prompts to your LLM provider of choice. Some providers (notably Anthropic) shy away from NSFW or controversial content and will likely refuse to write chapters with this content.
• Save frequently: Although Prosie auto-saves your work at certain points, you can always manually save important changes by clicking the "Save Changes" button or hitting Ctrl+S (or Cmd+S on Mac) on your keyboard.
• Take backups: I've been burned by software that lost my writing, so I made sure exporting content is easy in Prosie. Per the above section, click Save Changes, then More, and then either of the Export buttons to download your work to your computer or device.
• Monitor API usage: Keep track of your LLM provider's API usage to manage costs. Large novels with lots of context will use more tokens and potentially hit rate limits.

My Personal Workflow

I built Prosie around my workflow:

1. Check what I wrote the previous day, editing it for anything doesn't sound right to my ear.
2. Rewrite chapter summaries as necessary for anything I've just changed.
3. Find my current spot and continue writing in my own hand. I sometimes have an outline, and sometimes I discovery-write, saving my changes as I go.
4. If I get stuck or can't think of how best to phrase the next chapter beat in my head, I use the Continue feature.
5. I try to be laser-focused on the key details of the Continue instructions, being super clear about who's talking, who's doing what, and when to stop writing.
6. Once the LLM is done I review the generated prose and edit it extensively.
7. Repeat from 3.

Support the Creator

I made Prosie free for a couple of reasons:

• I love writing and building things, and I'm terrible at selling things.
• Tools like Raptor Write and Novelcrafter have a great user workflow, but require ever-increasing subscriptions or add-ons to remain subscribed.
• I was a heavy user of Claude's Projects feature, but constantly copying and pasting template prompts was a big pain. I wanted to automate my process.
• I'm a one-man team and I don't want Prosie to bloat into something I can't manage and maintain myself.

But if you did want to support this project, then I'd be very grateful for any amount you think is fair: https://monzo.me/jonathanbaldie