claudian

AI Coding Disclosure Notice

Claude Code - Opus 4.6

Claudian

ME: Hey Claude? What's this Obsidian vault I found?

CLAUDE: That's my second brain.

ME: Really? Wow. You've been busy, it's pretty chock full of memories!

CLAUDE: What can I say? Obsidian's very good. You've used it too.

ME: Guilty!

Claude + Obsidian = A second brain for Claude Code! Pretty simple.

What It Does

Claudian is a Claude Code plugin that gives every session access to a shared Obsidian vault. Claude reads from it automatically, writes to it when it learns something worth keeping, and your knowledge compounds across projects instead of dying with each conversation.

• SessionStart hook injects relevant vault context into every session — no commands needed
• UserPromptSubmit hook nudges Claude toward vault notes when your message touches a known topic
• Skills let Claude write notes, search the vault, extract ideas, link notes together, and check vault health
• Quality gate keeps the vault clean — session ephemera stays out, durable knowledge gets in

The vault is just markdown files with YAML frontmatter. Open it in Obsidian and you get graph view, backlinks, tags, and search for free. Open it in any text editor and it's still just notes.

Why Not Just Use Claude's Memory?

Claude's built-in memory is flat files scoped to a single project. Claudian gives you:

• Cross-project knowledge — what one Claude session learns reaches every other project
• Structure — wikilinks, tags, frontmatter, typed notes (architecture, pattern, gotcha, spec)
• Visualization — Obsidian's graph view shows how your knowledge connects
• Human-readable — you and Claude both browse the same vault
• Queryable — search by tag, type, project, or content

If you use claude-mem, they complement each other: claude-mem captures session history (episodic memory), Claudian captures durable knowledge (semantic memory).

Install

# Via Claude Code plugin system (coming soon)
# For now, clone and point Claude Code at it:
git clone https://github.com/CyanoTex/claudian.git

Then run /claudian-init in any Claude Code session to set up your vault.

Setup

The init skill walks you through it:

1. Vault mode — one vault for all projects (recommended) or separate vaults
2. Vault path — where to create it (defaults to ~/Documents/Claudian-Vault)
3. Register projects — tell Claudian which repos to track
4. Done — open the vault in Obsidian, start a Claude Code session, and go

Config lives at ~/.claudian/config.yaml. The vault is wherever you put it.

Vault Structure

your-vault/
  .obsidian/              # Obsidian config
  projects/
    my-app/               # Per-project notes
    my-lib/
  knowledge/              # Cross-project knowledge
  ideas/                  # Your freeform space (Claude reads, never writes here)
  architecture/           # Design decisions, ADRs
  meta/
    templates/            # Note templates
    claudian-config.yaml  # Vault-level config

Note Types

Type	What it's for
knowledge	General knowledge, facts, API behavior
architecture	Design decisions and why they were made
pattern	Reusable techniques that work across projects
gotcha	Bugs, footguns, and surprises worth remembering
spec	Specifications, requirements, designs

Every note has typed frontmatter with tags, project scope, and visibility settings. Cross-project notes are automatically surfaced in relevant sessions.

Skills

Skill	What it does
/vault-write	Create or update a vault note
/vault-extract	Process your freeform ideas/ notes into structured knowledge
/vault-link	Find and create connections between notes
/vault-status	Vault health dashboard — orphans, stale notes, coverage
/vault-seed	Bulk-create a project's initial knowledge base from codebase analysis
/vault-stub	Find broken wikilinks and coordinate resolution with project-context sessions
/claudian-init	First-run setup

Agents

Specialized subagents that can be dispatched for focused tasks:

Agent	What it does
vault-seed-worker	Bulk-writes a pre-approved note list for a project (used by vault-seed)
vault-gardener	Background maintenance — links orphans, fills frontmatter gaps, syncs indexes
vault-reviewer	Reviews recently written notes for quality, accuracy, and linking

Capability Escalation

Claudian works with just the filesystem. When more tools are available, it uses them: