Arcane RMCP

arcane-rmcp

Arcane Docker and Compose management over MCP and CLI with authenticated stdio and HTTP.

It exposes one MCP tool, arcane, plus the rarcane CLI. Agents can inspect Arcane environments, manage compose projects, containers, images, networks, volumes, registries, GitOps syncs, image updates, vulnerability findings, and system operations through stdio MCP, Streamable HTTP MCP, or direct shell commands.

30-second path: set RARCANE_API_URL and RARCANE_API_KEY, then run npx -y @dinglebear/rarcane status -> start loopback HTTP with RARCANE_MCP_HOST=127.0.0.1 npx -y @dinglebear/rarcane serve -> call tools/call with {"action":"status"}.

Status: operational RMCP upstream-client server. Write-capable; destructive Docker and Arcane operations require explicit confirmation. HTTP MCP supports loopback dev mode, static bearer tokens, and Google OAuth through lab-auth.

Not for: replacing Arcane, bypassing Docker or Arcane authorization, running arbitrary shell commands, storing registry or Git credentials, multi-tenant isolation, or passing Arcane API keys through MCP tool arguments.

Contents

• Naming
• Capabilities And Boundaries
• Install
• Quickstart
• Client Configuration
• Runtime Surfaces
• MCP Tool Reference
• CLI Reference
• Configuration
• Authentication
• Safety And Trust Model
• Architecture
• Distribution Contract
• Development
• Verification
• Deployment
• Troubleshooting
• Related Servers
• Documentation
• License

Naming

The repo and npm package use the upstream service name, while the shipped binary keeps the historical Rust CLI name rarcane. The MCP server may be registered as rarcane, but the tool clients call is arcane.

Capabilities And Boundaries

• Read Arcane status plus Docker environment, project, container, image, network, volume, registry, GitOps, update, vulnerability, and system state.
• Create, update, start, stop, restart, delete, prune, deploy, sync, scan, and back up supported Arcane resources through action/subaction dispatch.
• Enforce action scopes and destructive-operation confirmation before forwarding write operations to Arcane.
• Expose the quick_start prompt and rarcane://schema/mcp-tool resource for client-side discovery.
• Provide setup, doctor, and watch commands for local plugin/runtime checks.

Install

npm / npx

Run the stdio MCP server or CLI without a manual binary install:

npx -y @dinglebear/rarcane --help

npx -y @dinglebear/rarcane mcp npx -y @dinglebear/rarcane status

The npm package downloads rarcane during postinstall. Override download behavior only when testing packaging:

Build From Source

git clone https://github.com/dinglebear-ai/rarcane

cd rarcane cargo build --release ./target/release/rarcane --help

Minimum supported Rust version: 1.90.

Quickstart

1. Configure Arcane

Point the bridge at an existing Arcane API server:

export RARCANE_API_URL=https://arcane.example.com

export RARCANE_API_KEY=...

The API key is read from env or config only. Do not pass it in MCP tool arguments or CLI --params-json.

2. Run A Safe CLI Call

npx -y @dinglebear/rarcane status

3. Start Loopback HTTP MCP

RARCANE_MCP_HOST=127.0.0.1 npx -y @dinglebear/rarcane serve

In another shell:

curl -sf http://127.0.0.1:40110/health

4. Make A First MCP Call

curl -s -X POST http://127.0.0.1:40110/mcp \

-H "Content-Type: application/json" \ -H "Accept: application/json, text/event-stream" \ -d '{"jsonrpc":"2.0","id":1,"method":"tools/call","params":{"name":"arcane","arguments":{"action":"status"}}}'

Client Configuration

Claude Code Stdio

{

"mcpServers": { "rarcane": { "command": "npx", "args": ["-y", "arcane-rmcp", "mcp"], "env": { "RARCANE_API_URL": "https://arcane.example.com", "RARCANE_API_KEY": "..." } } } }

Claude Code HTTP

{

"mcpServers": { "rarcane": { "type": "http", "url": "http://127.0.0.1:40110/mcp", "headers": { "Authorization": "Bearer ${RARCANE_MCP_TOKEN}" } } } }

Codex / Labby Gateway

Register Arcane through Labby as an HTTP upstream when sharing one long-running server, or run it directly as stdio for local-only use.

[mcp_servers.rarcane]

command = "npx" args = ["-y", "arcane-rmcp", "mcp"]

Generic MCP JSON

{

"command": "rarcane", "args": ["mcp"], "env": { "RARCANE_API_URL": "https://arcane.example.com" } }

Do not put RARCANE_API_KEY, registry credentials, Git credentials, OAuth secrets, SSH keys, passwords, or upstream bearer tokens in MCP tool arguments. Use env, config files, or the MCP client's secret storage. MCP callers never provide credentials, tokens, keys, or secrets as action arguments.

Runtime Surfaces

MCP Tool Reference

One MCP tool is exposed: arcane. Pass the required action argument and, for most domains, a required subaction.

Action specs in src/actions.rs and the generated schema notes in docs/MCP_SCHEMA.md are the source of truth for required parameters.

Example read-only tool arguments:

{

"action": "container", "subaction": "list", "envId": "default" }

Example destructive operation:

{

"action": "container", "subaction": "stop", "envId": "default", "id": "my-container", "params": { "confirm": true } }

CLI Reference

rarcane exposes the same service layer as the MCP tool:

rarcane status

rarcane help --domain container rarcane call --action container --subaction list --env-id default rarcane call --action system --subaction docker-info --env-id default rarcane call --action container --subaction stop --env-id default --id my-container --confirm rarcane doctor --json rarcane watch --url http://127.0.0.1:40110 rarcane setup check rarcane setup repair

--params-json accepts action-specific JSON payloads. Do not use it to pass credentials.

Configuration

Host installs read ~/.rarcane/.env, ~/.rarcane/config.toml, and process env. Containers read /data/.env, /data/config.toml, and process env.

| RARCANE_HOME | ~/.rarcane | Conf