Plugins Adapter

An Envoy external processor (ext-proc) for configuring and invoking guardrails in an Envoy-based gateway like MCP Gateway.

Quick Install

Prerequisites

• kubectl configured in CLI

Full Dev Build

1. Install uv (if not already installed): https://docs.astral.sh/uv/getting-started/installation/

2. Install dependencies and build Protocol Buffers

   uv sync --group proto
   ./proto-build.sh

3. Verify src/ contains: /envoy, /validate, /xds, /udpa

4. Deploy to kind cluster

   # Replace nemocheck with a comma-separated list of plugins to include other plugins
   make all PLUGIN_DEPS=nemocheck

See detailed build instructions for manual build steps.

Configure Plugins

Update resources/config/config.yaml with list of plugins:

plugins:
  - name: my_plugin
    path: ./plugins/my_plugin
    enabled: true

Note: See plugins/examples for example plugins.

Then deploy:

make all

Detailed Documentation

• Build Instructions - Detailed protobuf build steps
• Deployment Guide - Deployment and debugging
• Architecture - System design and diagrams