Custom Plugin

If the built-in plugins do not cover your needs, you can write a custom plugin. A plugin is a plain TypeScript module that implements the Plugin API.

Plugin structure

import { definePlugin } from "@downcity/agent-plugin";

export default definePlugin({
  id: "my-plugin",
  name: "My Plugin",
  version: "1.0.0",

  async init(context) {
    // lifecycle hook: called when the Agent starts
  },

  async destroy(context) {
    // lifecycle hook: called when the Agent stops
  },

  tools: [
    {
      id: "myTool",
      description: "Does something useful",
      async handler(args) {
        return { result: "done" };
      },
    },
  ],
});

Key concepts

id — unique plugin identifier
init — startup hook for setup and connections
destroy — shutdown hook for cleanup
tools — functions the Agent can call during execution

Registering the plugin

Pass it to the Agent constructor:

import myPlugin from "./my-plugin";

const agent = new Agent({
  plugins: [myPlugin],
});

Continue with:

Custom Plugin

Custom Plugin

Plugin structure

Key concepts

Registering the plugin

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