CardGo

CardGo is a Chrome extension that gives you a set of reusable context cards about yourself and drops them into whichever AI chat you happen to be using. Instead of retyping who you are, what you're working on and how you like answers formatted every time you open ChatGPT, Claude, Gemini, Perplexity or Grok, you write that once as a card, then attach it to a conversation with a click. The cards are encrypted in your browser before they ever sync, so CardGo's own servers only hold ciphertext.

The problem is one every heavy AI user recognises. Each assistant has its own memory feature, and each one is a silo. What ChatGPT has learned about you doesn't follow you to Claude, and what either has decided to remember isn't something you wrote or can easily audit. So people keep a text file of boilerplate and paste it in, or they just repeat themselves. CardGo replaces the text file with something structured, portable and private.

Cards come in seven types that map to the things an assistant usually needs to know. Profile covers who you are, Now covers what you're currently doing, Goals and Guidance cover where you're headed and how you want to be helped, Memory and Timeline hold context and history, and Skills lists what you can do. You write them yourself, which is the point; this is user-authored context rather than model-generated inference. When you're in a supported chat, the extension shows your cards, you preview exactly what will be sent, and attaching one inserts it into the message box of that conversation. Only the card you attach goes to that provider, and only when you attach it. Getting started takes a few minutes. Install the extension from the Chrome Web Store, create an account if you want your cards to sync between machines, and write your first card. Profile is the obvious place to begin, since it's the one you'll attach most. Then open ChatGPT or Claude, pick the card from the extension, read the preview, and attach it. The card lands in the message box, you add your actual question, and you send it as normal. Nothing about the AI service changes; CardGo is only ever typing into the box on your behalf.

The encryption model is the part worth reading twice. Cards are encrypted locally using AES-256-GCM with a key generated on your device, and that key never leaves your browser. Sync moves ciphertext between your devices through CardGo's servers, which can't read it. The only party that ever sees a card in the clear is the AI provider you attach it in, at the moment you attach it. That's a meaningfully stronger posture than most productivity tools that store personal context.

It's for people who use more than one assistant and are tired of the cold start, and for anyone who is uneasy about built-in memory features deciding what to retain. Consultants and freelancers who switch context between clients get a lot out of it, since a card per client is a natural fit. Developers who keep a standing set of preferences about language, style and tooling can encode those once and stop repeating them.

Where it differs from native AI memory is control and portability. Built-in memory is model-generated, opaque and locked to one product. CardGo's cards are written by you, shown to you before they're sent, attached per conversation rather than always on, and work across five services from a single place. It works wherever those products let you type, because the insertion happens in the message box rather than through any special integration with the provider. Compared with the two usual workarounds, the difference is discipline. A text file of boilerplate works until it sprawls, goes stale, or gets pasted into the wrong chat with a client's details still in it. Custom instructions inside one product are tidy but stop at that product's border. CardGo makes you split context into typed cards, which is a little more work upfront and a lot less work every day after, and it means the sensitive parts are encrypted at rest rather than sitting in a notes app.

The limits are plain. It's Chrome only, so Safari and Firefox users are out for now, and it covers the web interfaces of those five assistants rather than desktop apps or APIs. Attaching is manual by design, which some people will find tedious after the novelty wears off. And the free tier caps you at seven cards, which is enough for most individuals but will feel tight for anyone running many client profiles. Access is free to start with no credit card. The free tier includes up to seven encrypted cards with cross-device sync, and the site doesn't currently list any paid plan, so there's nothing to compare against yet. The extension is in the Chrome Web Store, there's a signup and login for sync, and the privacy policy and a comparison page against built-in AI memory are published on the site.