ACP Bridge for Obsidian

Talk to ACP-compatible coding agents — Claude Code, Gemini CLI, Codex, and others — from inside Obsidian. The agent runs locally as a subprocess and can read and edit files in your vault, with per-call permission prompts.

Status: alpha — v0.1.0. Desktop-only. APIs around it are still moving fast; expect rough edges.

A note on provenance. Most of this code was written by Claude Opus in conversational pair-programming sessions, with a human at the wheel — reviewing every diff, running every build, and making the architectural calls. The human is enthusiastic, not an Obsidian-plugin veteran. The plugin is alpha; the agent you point it at can read and write files in your vault. Treat it accordingly: try it on a vault you don't mind losing first, skim the source if you're trusting it with anything sensitive, and report bugs cheerfully. There is, in the spirit of the genre, no warranty.

What it does

• Spawns a local ACP agent (default: npx -y @zed-industries/claude-code-acp) and connects over stdio.
• Adds a chat view (right sidebar by default; ribbon icon + command palette: "ACP Bridge: Open chat").
• Lets the agent read and write files inside your vault via ACP's fs/* methods.
• Asks for permission before tool calls. File reads can be auto-approved in settings.
• Surfaces tool calls, plans, and thoughts in the chat panel.

Install (manual, dev)

This is not on the community plugin catalog yet. To run locally:

git clone <this-repo> obsidian-acp-bridge
cd obsidian-acp-bridge
npm install
npm run build

Then copy or symlink the plugin into your test vault:

ln -s "$PWD" "/path/to/your/vault/.obsidian/plugins/acp-bridge"

The folder name inside .obsidian/plugins/ must equal acp-bridge (the id in manifest.json).

In Obsidian: Settings → Community plugins → Installed plugins → ACP Bridge → enable. Install the community Hot Reload plugin in your vault to get auto-reload during development.

Configure

Settings → Community plugins → ACP Bridge:

• Active profile — which configured agent to launch.
• Command / Arguments — executable + args for the active profile. Defaults to npx -y @zed-industries/claude-code-acp. You'll need an ANTHROPIC_API_KEY in your environment for that one to work.
• Auto-approve file reads — on by default; reads inside the vault won't prompt.
• Auto-approve writes inside the vault — off by default; every write asks.
• Log JSON-RPC traffic to console — off; turn on when an agent does something unexpected.

Use

1. Open the chat panel (ribbon icon, or command "ACP Bridge: Open chat").
2. Click Start in the panel header (or run command "ACP Bridge: Start agent session").
3. Type a message, Cmd/Ctrl+Enter to send.
4. Approve or reject any tool calls the agent requests.
5. Click Cancel turn to interrupt the agent mid-stream; Stop to kill the agent.

Limitations (v0.1)

• Desktop only (subprocess required; ACP-over-WebSocket isn't ready in the spec).
• One session at a time.
• One agent profile editable in the UI (the settings shape supports more — UI to add/remove profiles is pending).
• No terminal support.
• No MCP forwarding — Obsidian doesn't pass any MCP servers to the agent yet.
• Plain-text rendering of agent output. No Markdown/syntax highlighting yet.
• Mobile content blocks (image, audio, resource) show as [<type>] placeholders.

Security model

• The agent runs with your user's permissions. Don't run an agent you don't trust.
• File access is restricted to the vault root via path normalization. Paths outside the vault are rejected by the client.
• Writes default to prompting on every call. Auto-approval is opt-in per category.
• The plugin makes no network requests of its own; the agent may.

License

MIT. See LICENSE.