Riff

Anyone who posts for a living knows the late-afternoon slump. There are still thirty comments to answer, and each deserves something better than "Thanks!" The obvious shortcut means pasting other people's messages into a cloud chatbot and paying monthly for the privilege.

Riff takes a different route. It's a free extension for Chrome, Brave and Edge on desktop, and the AI model runs on your own computer. A side panel opens beside X, LinkedIn, Threads, Facebook, Instagram or YouTube, and beside Slack and Teams in their web versions. It reads the post you're looking at and drafts a reply. There's also Riff Home, a full tab for ordinary private chat.

The part worth underlining is what it won't do. Riff's help pages put it bluntly: "Riff never presses Reply, Comment, Post, Share, Send or Enter." Insert fills the box and stops. You read the draft and you send it, every time.

A reply tool is only useful if the drafts sound like you. Riff builds a voice profile through a short interview with the model. It then checks each new draft against your last 60 replies and rewrites it if you're repeating yourself. There's a Never say list too. Out of the box it already bans "game-changer," "delve," "synergy" and "great post," which tells you what its makers were tired of reading.

For models, you pick one of three. Gemini Nano is built into Chrome and writes in five languages. Gemma 4 is a one-time download from Hugging Face and covers all sixteen. Or you can connect LM Studio or Ollama running on your machine. None of it needs an API key.

Riff costs nothing. There's no account, no subscription and no payment. It comes from Zima Media OÜ, an Estonian company that gives its registry code and Tallinn address in the privacy policy.

That policy, effective November 6, 2026, says the extension has no servers, analytics, ads or trackers, and that your chats, voice profile and reply history stay in the browser. The only network traffic it describes is the model download and any local model apps you choose to connect. Keep in mind that drafting a reply means reading the conversation on screen, including other people's messages, even though that happens on your device.

Two loose ends. The privacy policy lists a Safari version and only four social sites, while the homepage names Chrome, Brave and Edge and a longer list, so check the Chrome Web Store listing for what's current. And local models are big downloads, so make sure you have the disk space.

If you answer comments all day and would rather your drafts never left your laptop, Riff is worth an install.