Companion for Claude

Cowork with Claude inside your Obsidian vault. Companion
brings vault-aware chat, reviewable agent work, interactive artifacts, and an
evidence-backed research workflow into Obsidian while your notes remain the
source of truth.

Install from the Obsidian community store
· Getting started
· All guides

Install

1. Open Settings → Community plugins → Browse.
2. Search for Companion for Claude, then install and enable it.
3. Open Companion and choose a connection:
   • Claude Code sign-in on desktop, using the installed claude command.
   • Anthropic API on desktop or mobile, using your own credential.
   • Local model through Ollama or an OpenAI-compatible endpoint.
4. Open a note, enable the Note context chip, and send your first message.

Walk through setup and the first useful workflows →

What Companion adds to Obsidian

• Vault-aware chat with the active note, selection, links, search results,
  folders, PDFs, images, and pasted screenshots as context.
• Agent mode that can search, read, and follow links while showing every tool
  call; writes remain behind confirmation.
• Reviewable edits with per-hunk acceptance before a note changes.
• Research Desk for sources, evidence, claims, outlines,
  drafts, and deterministic assurance checks.
• Interactive claude-html artifacts, native Canvas files, and Obsidian
  Bases generated from your vault.
• On-device semantic search on desktop and mobile, including page-located
  PDF chunks.
• Durable conversations that survive restarts. An interrupted model turn
  returns as stopped work with a Retry action.
• Multiple chat tabs, each with its own conversation, via the "New chat tab" command.
• Chat projects: scope a conversation to a chat-project note or a
  Research Desk project — its instructions and pinned notes join the system
  prompt, and automatic vault search narrows to its folder. Choose one from
  the "@" menu or the "Chat: choose project" command.
• Optional integrations: a loopback MCP bridge for live-vault tools, and an
  MCP client for servers you explicitly configure.

The product overview stays in the repository README. Detailed
behavior and setup live in the guides:

• Agent mode, edits, and guardrails
• Research Desk
• Interactive artifacts
• Local models and semantic search
• Claude Code and the MCP bridge
• Authentication and cost
• Architecture
• FAQ

Desktop agents

Companion chat can run directly through Claude Code. Choose Claude Code — your
subscription under Connection and Companion uses one resumable CLI session
per saved conversation. This backend does not require the MCP bridge.

For portable Claude Code workflows using the official Obsidian CLI:

/plugin marketplace add cavi-ai/plugins
/plugin install obsidian-agent@cavi-ai

The optional Companion MCP bridge is for Claude Desktop and advanced clients
that need live research, semantic-search, ontology, or controlled-write tools.
It is off by default, binds only to 127.0.0.1, requires a non-empty bearer
token, and does not advertise mutation tools until Allow writes is enabled.

Set up desktop integrations and review the tool boundary →

What leaves your machine

Companion has no telemetry or analytics. Network activity follows an action you
take or a backend you choose.

• Anthropic or your API base URL: a direct-API chat, agent, or utility turn
  sends the prompt, attached vault context, and system prompt.
• The installed claude command: a desktop Claude Code turn sends the
  prompt and attached vault context to the CLI, which owns authentication and
  service traffic.
• Your Ollama host or OpenAI-compatible endpoint: selecting that backend
  sends the request to the server you run.
• Tag classifier model: Check with model in Optimize brain sends tag
  names and up to 3 note titles per tag to the configured classifier model; in
  the background it runs only when the classifier is served from this machine
  or a private-network address (localhost or a loopback or private-range IP);
  no other host name qualifies.
• Hugging Face and jsDelivr: the one-time embedding download requests only
  the model and ONNX runtime after you approve it; both are cached.
• Cloud-session services: Send to cloud Claude session sends the prompt
  and attached note context to your configured routine fire URL. Pulling cloud
  replies sends the repository, branch, and folder you configured to GitHub.
• Research services: an explicit discovery or import action sends search
  terms or bibliographic identifiers to OpenAlex, Crossref, arXiv, or Zotero.
• Web pages and search services: web capture, web_fetch, and web_search
  send only the URL or query you supplied.
• External MCP servers: a tool call you confirm sends that tool's arguments
  to the server you configured.

Semantic and keyword indexes stay on device. Credentials live in Obsidian's
encrypted secret storage, never the vault-synced data.json. Desktop shell
execution uses argument arrays rather than shell strings and covers only the
Claude/Obsidian CLIs, browsers you select for artifacts, and stdio MCP servers
you configure; it is disabled on mobile.

For the complete endpoint, WebAssembly, site-specific capture, and cloud-session
details, see Authentication and cost,
Local models, and the
architecture guide.

Artifact security

Companion renders a fenced ```claude-html block in a sandboxed iframe
with scripts allowed but same-origin access denied. A restrictive content
security policy blocks network requests and form submissions, so the artifact
cannot reach the vault, cookies, or remote services. Saving an artifact writes
the same block to a normal Markdown note.

Artifact behavior and authoring examples →

Development and testing

All commands run from this directory:

pnpm install
pnpm run typecheck
pnpm run lint
pnpm test
pnpm run docs:verify
pnpm run build

To install a development build, copy main.js, manifest.json, and
styles.css to <vault>/.obsidian/plugins/claude-companion/, then enable
Companion for Claude in Community plugins. pnpm run dev watches and
rebuilds main.js for active development.

See CONTRIBUTING.md for the full gate and release
workflow.

Releases

• Store listing: Companion for Claude
• Source: cavi-ai/claude-obsidian
• Release artifacts: cavi-ai/companion-for-claude
• Version lockstep: manifest.json, versions.json, package.json, and the
  git tag use the same exact version.

License

MIT — see LICENSE. Third-party attribution is in
NOTICE.