Reply in your voice.
Not ChatGPT's.

ReplySathi doesn't automate posting. It drafts text, puts it in X's own reply box, and stops — you read it, edit it, and press Reply yourself. That's the same category as a keyboard suggestion, not a bot. X's automation rules target unattended posting, spam and bulk engagement, and we deliberately make all three impossible. We'd still say read X's rules yourself and use it like a person, not a machine gun.

No. There is no code path in the extension that clicks X's Reply button. That is a deliberate design decision, not an unshipped feature, and it isn't coming.

Very little, and all of it tied to the Google account you sign in with: your email and name from that account, which plan you're on, and how many replies you've generated today. The daily counter deletes itself after 48 hours. There's also a plain signup log — an email and a date per new account — and that is the whole database. We don't store the posts you click or the replies we draft, we never see your DMs, and we can't post as you — there's no X login, no X API token, nothing attached to your X account.

The text of that post — plus a bit of context like the author's name, quoted post or thread above it, and your voice profile — goes to our server, which builds the prompt and sends it to the model provider (Anthropic today). The drafts come back to your browser. Nothing on that round trip gets written to a database: not the post, not the drafts, not your voice profile, which lives in your browser's extension storage and is sent with each request rather than kept by us. The provider holds API traffic briefly for abuse monitoring under its own policy; nothing there trains a model, and nothing on our side is sold to anyone.

In proportion to the effort you put into the voice profile. "Casual and friendly" gets you a generic bot. Four of your real tweets pasted in gets you something your followers won't clock as AI. It takes two minutes and it's the whole product — there's a worked example of a good profile on the getting-started page.

Chrome, Edge, Brave, Arc — anything Chromium-based. Firefox and Safari aren't supported yet.

No, and there's nowhere to put one. Earlier builds asked you to paste your own key; that's gone. You install the extension, sign in with Google, and click ✦ — we run the model on our own key and our own servers. The free plan is 6 replies a day, 60 a month, with no card, and there's no OpenAI console, no billing dashboard, no usage bill to be surprised by.

From the extension itself. Click ✦ on any post, or open the extension popup, and hit Sign in with Google. It opens Google's own window, you pick your account, it closes. No password to make, no confirmation email to hunt for. There's nothing to sign into on this website — the account only exists inside the extension.