AI writing tools that don't train on your writing

It is among the first questions a serious writer asks about AI tools, and one of the most reasonable. If I write my novel with this thing, does my manuscript become training data? The answer has three layers, and most marketing answers stop at whichever layer flatters the product. Here are all three.

Layer one: the tool

Where does the writing application itself put your manuscript? Most AI writing tools are web applications, so your book lives on the company's servers and your protection is whatever the privacy policy says this year. That is not an accusation. Reputable tools state that they do not train on user manuscripts. A policy is a promise, though — and policies are amended, and companies are acquired.

The stronger position is architectural. A tool that never possesses your manuscript cannot train on it, cannot leak it, and cannot change its mind about it. Proselon is built that way deliberately, being a desktop application in which your book is stored as plain files in your own Documents folder, with no cloud manuscript storage anywhere in the product. We do not train on your writing for the dullest of reasons. We never receive it.

Layer two: the engine

Whatever the tool does, the AI engine sees what you send it. That is how co-writing works at all. So the second question concerns what the provider does with those conversations, and the answer is that it is a setting, and that it varies by plan.

The pattern across providers, as of mid-2026, runs like this. Free consumer tiers are likelier to use conversations for model training by default. Paid consumer plans vary and generally offer an opt-out, and business and enterprise tiers typically do not train on customer data at all. The specifics move around too much for us to pin down responsibly per provider in a guide. The reliable move is to open the data or privacy settings of your own account on ChatGPT, Claude, Gemini or Grok and read the training toggle. It takes two minutes, and since it is the same policy already governing your ordinary chats with that AI, checking once covers both.

Worth knowing even if you never touch an AI tool built for writers. If you are drafting your novel in a free chat tab today, layer two applies to you at this moment.

Layer three: the flat no

Some writers need the answer to be that nothing of theirs goes anywhere, ever, with no settings and no policies and no trust required of them. That option exists. Run an open model on your own computer through Ollama or LM Studio and the entire loop occurs on your machine. Nothing is transmitted and nothing is stored elsewhere. There is nothing anywhere for anyone to train upon.

The trade-offs are real, since local models write below the frontier engines and capable hardware is not optional. We weigh them in Can you write a novel with AI for free? Proselon supports local models as a first-class engine for precisely this case. Co-writer included, internet not.

The four questions

Ask these of any AI writing tool, in this order.

Where does my manuscript live? Your own computer beats a server, and files you can open in anything beat a database you must export from.

Does the tool itself train on or retain my text? Look for architecture ("we do not store your manuscript") rather than reassurance ("we care about your privacy").

Which engine sees my text, under whose account, with training set to what? Read the toggle in your own engine account.

Is there a zero-transmission mode? Local model support is the only complete answer to that one.

Proselon's four answers, in the same order. Your manuscript stays in your Documents folder. No, and no. Your own account and your own toggle. Yes, through Ollama and LM Studio. There is more in our FAQ, including what all of this means for fanfiction and explicit work. The application is free for 30 days, and your manuscript sits in your own files from the first minute, which is rather the point of it.