diff --git a/typings/plugin.d.ts b/typings/plugin.d.ts
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+++ b/typings/plugin.d.ts
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+/**
+ * This file describes the code-server plugin API for adding new applications.
+ */
+import { Logger } from "@coder/logger"
+import * as express from "express"
+
+/**
+ * Overlay
+ *
+ * The homepage of code-server will launch into VS Code. However, there will be an overlay
+ * button that when clicked, will show all available applications with their names,
+ * icons and provider plugins. When one clicks on an app's icon, they will be directed
+ * to <code-server-root>/<plugin-name>/<app-name> to access the application.
+ */
+
+/**
+ * Plugins
+ *
+ * Plugins are just node modules.
+ *
+ * code-server uses $CS_PLUGIN_PATH to find plugins. Each subdirectory in
+ * $CS_PLUGIN_PATH with a package.json where the engine is code-server is
+ * a valid plugin.
+ *
+ * e.g. CS_PLUGIN_PATH=/tmp/nhooyr:/tmp/ash will cause code-server to search
+ * /tmp/nhooyr and then /tmp/ash for plugins.
+ *
+ * CS_PLUGIN_PATH defaults to
+ * ~/.local/share/code-server/plugins:/usr/share/code-server/plugins
+ * if unset.
+ *
+ * code-server also uses $CS_PLUGIN to find plugins.
+ *
+ * e.g. CS_PLUGIN=/tmp/will:/tmp/teffen will cause code-server to load
+ * /tmp/will and /tmp/teffen as plugins.
+ *
+ * Built in plugins are also loaded from __dirname/../plugins
+ *
+ * Priority is $CS_PLUGIN, $CS_PLUGIN_PATH and then the builtin plugins.
+ * After the search is complete, plugins will be required in first found order and
+ * initialized. See the Plugin interface for details.
+ *
+ * There is also a /api/applications endpoint to allow programmatic access to all
+ * available applications. It could be used to create a custom application dashboard
+ * for example.
+ */
+
+/**
+ * Your plugin module must implement this interface.
+ *
+ * The plugin's name, description and version are fetched from its module's package.json
+ *
+ * The plugin's router will be mounted at <code-sever-root>/<plugin-name>
+ *
+ * If two plugins are found with the exact same name, then code-server will
+ * use the last one and emit a warning.
+ */
+export interface Plugin {
+  /**
+   * init is called so that the plugin may initialize itself with the config.
+   */
+  init(config: PluginConfig): void
+
+  /**
+   * Returns the plugin's router.
+   */
+  router(): express.Router
+
+  /**
+   * code-server uses this to collect the list of applications that
+   * the plugin can currently provide.
+   * It is called when /api/applications is hit or the overlay needs to
+   * refresh the list of applications
+   *
+   * Ensure this is as fast as possible.
+   */
+  applications(): Application[] | Promise<Application[]>
+}
+
+/**
+ * PluginConfig contains the configuration required for initializing
+ * a plugin.
+ */
+export interface PluginConfig {
+  /**
+   * All plugin logs should be logged via this logger.
+   */
+  readonly logger: Logger
+}
+
+/**
+ * Application represents a user accessible application.
+ *
+ * When the user clicks on the icon in the overlay, they will be
+ * redirected to <code-server-root>/<plugin-name>/<app-name>
+ * where the application should be accessible.
+ *
+ * If the app's name is the same as the plugin's name then
+ * <code-server-root>/<plugin-name> will be used instead.
+ */
+export interface Application {
+  readonly name: string
+  readonly version: string
+
+  /**
+   * The path at which the icon for this application can be accessed.
+   * <code-server-root>/<plugin-name>/<app-name>/<icon-path>
+   */
+  readonly iconPath: string
+}