Every chatstarts at zero.

Claudian gives it somewhere to remember — Markdown files on your own machine.

Download for WindowsDownload for MacView on GitHubDocs →
Windows 10 · 11 · macOS 12+ · preview 1.9.1 · no account
how to set it up →
0AI surfacesClaude · ChatGPT · Codex
0acceptance suitesrun before every release
OAuth 2.0with PKCEscoped tokens, one per surface
Gitevery write is a diffinspect it, revert it
LocalMarkdown on your diskno vault upload, ever
it talks · it writes · it remembers

Watch where it goes.

keep /api/mcp on the tunnel
--- tags: [claudian, architecture] updated: 2026-09-04 ---

Cloudflare path split

Public site on Workers. [[/api/mcp]] stays on the tunnel.

You explained it
last week.
It forgot.

so… who are you again
last week

the tunnel keeps /api/mcp

got it — noted.

session ended
12 days ago

never use my assistant names in public

understood.

session ended
3 weeks ago

raw chat isn't memory

makes sense.

session ended
what it is already holding
[[Home]][[Vault Protocol]][[Claudian]][[Control Panel]][[Second Brain]][[Graph View]][[Map of Content]][[Projects]][[Technical Patterns]][[Open Loops]][[System]][[Working Agreements]][[Decisions]][[Cost of Being Wrong]][[Adapters]][[Gateway]][[Home]][[Vault Protocol]][[Claudian]][[Control Panel]][[Second Brain]][[Graph View]][[Map of Content]][[Projects]][[Technical Patterns]][[Open Loops]][[System]][[Working Agreements]][[Decisions]][[Cost of Being Wrong]][[Adapters]][[Gateway]]
[[Gateway]][[Adapters]][[Cost of Being Wrong]][[Decisions]][[Working Agreements]][[System]][[Open Loops]][[Technical Patterns]][[Projects]][[Map of Content]][[Graph View]][[Second Brain]][[Control Panel]][[Claudian]][[Vault Protocol]][[Home]][[Gateway]][[Adapters]][[Cost of Being Wrong]][[Decisions]][[Working Agreements]][[System]][[Open Loops]][[Technical Patterns]][[Projects]][[Map of Content]][[Graph View]][[Second Brain]][[Control Panel]][[Claudian]][[Vault Protocol]][[Home]]

Your memory, carried forward.

Explore the documentation →

One file. Every model.

The protocol is designed for shared memory across providers. The desktop preview connects Claude Code, Codex, Gemini CLI, Antigravity and Antigravity CLI through local skills and startup rules, and Claude Desktop through a local MCP server with named, scoped capabilities. ChatGPT cannot start a local process, so it connects over a published address.

Read how it works →
three models · one memory

One file.
Every model.

Claudian / Control Panel.md3 connected
## System
- [ ] Connect a date-bearing source
- [ ] Cloudflare path split
- [x] claude.ai connector — [[Connected Tools]]
## Open questions
- Where the always-on node runs
ClaudeChatGPTCodex
stored on your machine · only allowed context leaves it
~/Desktop/Claudian/*.md
1 / 7 · Shared memory
same rules · different voice

Swap the model.
Keep the memory.

~/Desktop/Claudian/*.mdone folder · never uploaded

Brains you can install.

Curated knowledge. Connected to your memory.

Marketplace · Coming soon

Claudian Library

AI Engineering

Knowledge pack
Markdown edition
Build

AI Engineering

Architectures, evaluation methods and technical decisions for building with AI.

0.00Preview price · Sales not open

Claudian Library

Business

Knowledge pack
Markdown edition
Decide

Business

Strategy, business models and decision frameworks in one connected knowledge pack.

0.00Preview price · Sales not open

Claudian Library

Psychology

Knowledge pack
Markdown edition
Understand

Psychology

A reference collection on attention, learning and behaviour for thoughtful exploration.

0.00Preview price · Sales not open

Install beside your notes. Keep the sources. Choose what your AI can read.

Checkout opens at launch
Tested with
Claude Code terminal · rule + skillCodex terminal · rule + skill
Runs on
Windows 10 · 11macOS 12+ · Apple silicon · Intel
Requires
Obsidian your existing vaultAn account with the model you already useNo API key unless your provider needs one
Last tested September 2026 · versions listed above
claudian.app

Build your second brain. Keep it yours.

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