Riff: fresh replies and posts for X, LinkedIn, Facebook & Instagram

Fresh replies, new posts and first messages in your voice, plus your DMs, Slack and Teams. Runs on your device.

Riff writes replies, posts and messages in your voice, from the point you want to make. It works on X, LinkedIn, Facebook and Instagram, and in your work chat too. It runs on Gemini Nano, the AI model built into Chrome, so your notes, posts and messages stay on your computer. Riff never posts or sends anything for you. RIFF A POST Click into a site's own box for a new post or caption and Riff switches from "Riff a reply" to "Riff a post". You get a clean canvas that works like a chat: 1. Drop your rough notes and press Enter. Riff drafts the post for that site. 2. Ask for changes in plain words: "shorter", "open with the number", "less formal". Every answer is a new version you can go back to, and you can edit the draft yourself. 3. Ask for 3 hooks and pick the opening line you like. Riff rebuilds the post around it. 4. Rework in one click: Stronger hook, Shorter, Add a story, Scannable, Less salesy, End with a question, Add proof or More human. 5. Repurpose the draft for another site, or turn it into a first message. 6. Insert puts it in the post box. You read it and press Post. The canvas stays until you press Clear, so a topic you come back to is still there. Riff works only from the facts in your notes: no invented results, clients or numbers. POST DIALS - Post type: Story, Lesson, How-to, Announcement, Result, Hot take, Question, Behind the scenes or Event / offer, or Auto - Goal: Comments, Reach, Clicks, Leads or Authority - Hook: Bold claim, Question, Number, Story, Contrarian or "How I…" - Ending: Ask, Comment a word, DM me, Link, Link in comments, Link in bio, Book a call or none - Format (Airy, Paragraphs, List or Emoji bullets), hashtags (off, 1–3 or the site's max) and length - Presets: save the dials for a post you write often and set them again in one click Riff also shows the part of your post that appears before "see more", so you can check the hook. FIRST MESSAGES Start a new conversation and Riff writes the first message to that person. Pick why you're writing (Intro, Follow-up, Ask, Thank you or Congrats) and how you know them (Cold, Met before or Customer). It never claims you've met or talked before unless your notes say so. RIFF A REPLY 1. Pick the post. Click the small Riff wave button in the post's action row, or open the post's own reply or comment box. Riff reads the post, plus the quoted post or the comment you're answering. 2. Paste your point. Write it rough. Riff says it in new words for this post. 3. Set the pedal. Choose how smart, how salesy and how adventurous the reply should be. 4. Press Enter. The reply streams in, written for that one post. 5. Rework it in one click: Shorter, Punchier, Softer pitch, Bolder, More human or + Question. 6. Insert. Riff opens the post's reply or comment box if needed and puts the draft in it. You press Reply, Comment or Post yourself. YOUR DMS TOO Riff answers your direct messages on all four sites, X Chat included. Click into a chat's message box or the Riff button next to it, and Riff reads the conversation. Your point is optional: leave it empty and Riff works out the reply from what they wrote. It never agrees to a time, a price or a yes or no for you, and when your message is the latest it writes a friendly follow-up. Insert puts the draft in the message box; you press Send. WORK CHAT Riff also answers DMs, channels and threads in Slack, and chats and channel conversations in Microsoft Teams, on the web (not in their desktop apps). It reads the conversation you're in and writes like a helpful colleague: clear, brief and in the tone of the thread, with no headings or sign-offs. Start a new chat or open a quiet channel, and it writes a first message instead. Insert puts the draft in the message box; Riff never presses Send for you. WRITES LIKE EACH SITE Riff detects the site from the tab you're on and switches limits, tone and link handling with it. - X: short and punchy, counted the way the site counts (links count as 23 characters). Write a single post or a numbered thread; threads fill the boxes you have open, so press + for each extra post, then Insert again. - LinkedIn: real perspective instead of "Great post" in comments, and posts up to 3,000 characters with short lines that read well in the feed - Facebook: warm and conversational, on feed posts, groups and pages - Instagram: casual and short. Links aren't clickable in its comments or captions, so Riff leaves them out and can point people to your bio instead Not on one of these sites? Paste any post into the panel, or switch to "Riff a post", and choose which site you're writing for. THE PEDAL (REPLIES) - Intelligence: Plain, Sharp or Expert - Sales tactic: Auto, Value first, Curiosity, Social proof, Problem → fix, Question, Mini story, Contrarian or Direct - Pitch: Off, Hint, Clear or Direct - Spin: Safe through Wild - More: tone, length, emoji and language SOUNDS LIKE YOU - Voice: tell Riff once who you are, what you offer, who it's for and how you sound. Add a reply and up to two posts you wrote, and Riff copies their voice and shape, never their words. - Brand voices: write as a brand you run, with its own offer, audience, tone, sample posts and hashtags. - Library: keep your links with "use for" notes, and Auto picks the right one. Save the points you make often. - Freshness check: each draft is compared with your notes and your recent replies and posts, and Riff redrafts it if it repeats them or uses a phrase from your "Never say" list. Em dashes and hashtags are left out by default, and tired post openers ("Excited to announce", "Unpopular opinion") are on a list you can edit. PRIVATE BY DESIGN - Gemini Nano runs on your device. No account, no API key, no servers, no monthly bill. - Your settings, notes, drafts, links, saved points, presets and history stay in Chrome's storage on this computer. - Riff never posts or sends anything. It fills the box, and you're the one who presses Reply, Comment, Post or Send. REQUIREMENTS - Desktop Chrome 138 or newer on Windows 10/11, macOS 13+, Linux or a Chromebook Plus - At least 22 GB of free disk space on the drive with your Chrome profile, for the one-time Gemini Nano download - A GPU with more than 4 GB of video memory, or 16 GB of RAM and 4 or more CPU cores - An unmetered connection (Wi-Fi or Ethernet) for the one-time download The first time you open Riff, it walks you through downloading Gemini Nano. After that the model runs offline on your machine. SHORTCUTS Alt+Shift+R opens Riff. Enter riffs, Shift+Enter adds a line, Ctrl/⌘+Enter inserts the draft, Esc stops a riff. Riff is an independent extension. It isn't affiliated with or endorsed by Google or by the makers of the sites and apps it works with.