Introducing Liminal: a shared workspace & 2nd brain for you, your agent, and your team

Hey Product Hunt 👋

I'm Justin, the maker of Liminal, and I'm stoked to finally share what I've been building!

Heads up: this is the first cut. I'm launching now to find out if the friction I've been feeling is real for other people too. All feedback is welcome, and please let me know if you run into any bugs or problems, I'll get them fix asap!

Quick backstory

Last summer, the way I work changed. Agents got good enough to become the place I did the work. Claude Code became my main interface, the intelligence layer everything flowed through. My job shifted from writing and producing to directing an agent to do it.

Notion and Google Docs weren't built for this. They were bolting agents into their apps, but that's not where my agent lived, and their MCPs were slow and expensive to talk to. Claude Code worked much better and faster with local markdown files, a format the agent already speaks. So I stopped writing in Notion and Google Docs and went all in on local markdown.

I was doing all of this in VS Code because that's where I coded. But viewing and editing markdown there is clunky. You use the preview to render it nicely, then jump to the raw side to actually edit. So I built a WYSIWYG editor on top of the local files.

Then I tried to share something. Nobody wants to be sent a raw markdown file, and Google Drive doesn't render it nicely. Passing files back and forth killed any hope of collaboration. So I built real-time live collaboration on top of local files: a lightweight CLI watches your workspace folder and syncs bidirectionally with the cloud. Share a link and your teammate opens the same live workspace in a browser. Their edits land back on your disk instantly.

Once that worked, the thing I hadn't designed for showed up. My agent and my teammates' agents were all reading and writing into the same workspace. Liminal had quietly become a shared second brain. Company knowledge that keeps updating and compounding as the team works, sitting on every agent's local disk as plain files they can directly access.

What Liminal is

A collaborative workspace for humans, agents, and teams. Your AI-native second brain. Bring your own agents. Own your files.

How it works:

🟢 Work with your agent, not just through it. Your agent writes files to disk in markdown or HTML. Liminal renders them as clean UI the moment they save. Review and edit naturally in the browser, without wrestling with raw markdown.

🟢 Share instantly, without the friction. A lightweight CLI syncs your workspace to the cloud in real time. Send a link and your teammate is in the same live workspace. No sending markdown over Slack, no hosting your own HTML, no waiting on Google Drive.

🟢 A shared second brain for every agent on the team. Files live locally, so every agent has direct access to everything the team has written, decided, and learned. No external calls, no lag, no losing context between sessions.

🟢 No middleman, no MCP tax. Direct file access means no MCP round-trips, no proprietary formats, no wasted tokens. Context is cheap, fast, and always fresh.

The ask

Would love your feedback, especially if you're living in Claude Code, Codex, or another agent all day: does this map to your experience, or am I solving a problem only I have?

Justin
https://useliminal.xyz