MCP Server
Query your service graph from AI coding tools.
Overview
The Arcanon MCP server lets AI coding tools query your service graph directly during development. It ships inside the Claude Code plugin — installing the plugin auto-registers the server, so Claude can answer cross-repo impact and drift questions without any extra wiring.
For MCP clients outside Claude Code, the same server runs as a stdio process from the plugin's scripts/mcp-wrapper.sh.
Setup
Inside Claude Code
Install the plugin (instructions), log in with /arcanon:login arc_your_key_here, and run /arcanon:map to populate the graph. The MCP server is active for the session — no .mcp.json entry needed.
Other MCP clients
Point your client at the plugin's wrapper script and pass your API key via environment variable:
{
"mcpServers": {
"arcanon": {
"command": "/path/to/arcanon/scripts/mcp-wrapper.sh",
"env": {
"ARCANON_API_KEY": "arc_your_key_here"
}
}
}
}Available Tools
| Tool | Description |
|---|---|
impact_query | Which services consume (or are consumed by) a given service — direct or transitive |
impact_changed | Services affected by changed files in the current git working tree |
impact_graph | Dependency subgraph (nodes + edges) for a service, up to N hops |
impact_search | Full-text search across connections by path, protocol, or file name |
impact_scan | Trigger a dependency scan via the local worker |
drift_versions | Dependency version mismatches across repos (CRITICAL on exact mismatch, WARN on range) |
drift_types | Shared type/interface/struct mismatches across same-language repos |
drift_openapi | OpenAPI spec breaking changes (uses oasdiff when available) |
Data is read from the local graph built by /arcanon:map, so tool calls stay fast and work offline.