CozyVTT-Agent

CozyVTT-Agent is an installed, trusted CozyVTT plugin that adapts the host's campaign-scoped capability interface to MCP Streamable HTTP. CozyVTT owns OAuth, campaign authorization, approvals, command execution, replay, audit, and result validation. This plugin owns MCP protocol behavior only.

It does not import CozyVTT backend code, access its database, or proxy through an agent-specific HTTP API.

Development

npm install
npm test

Build an Installable Package

Use the same review key configured in CozyVTT. The command creates a bundled, signed package under build/cozyvtt-agent/ and prints its immutable checksum.

TRUSTED_EXTENSION_REVIEW_KEY=local-review-key npm run package:extension

Configure CozyVTT with:

EXTENSION_PACKAGE_ROOT=/path/to/CozyVTT-Agent/build
TRUSTED_EXTENSION_REVIEW_KEY=local-review-key
TRUSTED_EXTENSION_ALLOWLIST='[{"extensionId":"cozyvtt.agent","version":"0.2.0","checksum":"sha256:..."}]'

An administrator can then install and activate cozyvtt.agent through the generic extension administration API. Its MCP resource is exposed at /api/plugin-transports/cozyvtt.agent/mcp; OAuth discovery and token issuance are provided by CozyVTT.