Snapwit

Snapwit is a browser extension for Chrome and Edge on desktop. It drafts replies to posts on X, LinkedIn and Reddit right inside the reply box. You pick a tone (agree, disagree, supportive, funny or ask a question), edit the draft and post it yourself. Drafts are adjusted per platform: short on X, longer on LinkedIn, plain and not salesy on Reddit. You can also define custom tones.

To match your writing style, you paste in a few of your past replies. Snapwit looks at sentence length, punctuation, emoji use and how you open and close, then applies that to its drafts. You can also tell it what you're building and who it's for so replies stay on topic. Voice matching is in beta. A separate Enhance tool works in any browser text field and can fix grammar, shorten, expand, rewrite or translate selected text, with support for custom actions.

Nothing is posted automatically. The extension only reads the post you're replying to, and only when you click a tone. It runs on OpenAI's GPT models, and bring-your-own-key is on the roadmap. A free tier comes with 10 one-time credits. Paid plans are monthly, annual or a one-time Lifetime purchase.