diff --git a/src/index.ts b/src/index.ts
index b11d055..8ea4a7f 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -10,5 +10,13 @@ export * from "./getJavaConfig";
 export * from "./installJava";
 
 export * from "./commands/restartServer";
+
 export * from "./interfaces/TreeViewProtocol";
 export * from "./interfaces/MetalsInitializationOptions";
+export * from "./interfaces/ClientCommands";
+export * from "./interfaces/ServerCommands";
+export * from "./interfaces/MetalsSlowTask";
+export * from "./interfaces/Extensions";
+export * from "./interfaces/MetalsInputBox";
+export * from "./interfaces/MetalsQuickPick";
+export * from "./interfaces/MetalsStatus";
diff --git a/src/interfaces/ClientCommands.ts b/src/interfaces/ClientCommands.ts
new file mode 100644
index 0000000..9ef854c
--- /dev/null
+++ b/src/interfaces/ClientCommands.ts
@@ -0,0 +1,50 @@
+/**
+ * These are all of the client commands that Metals supports. Note that not support
+ * may vary based on the `InitializationSettings` the client sets.
+ *
+ *  - https://scalameta.org/metals/docs/editors/new-editor.html#metals-client-commands
+ */
+export const ClientCommands = {
+  /**
+   * A client command that should be forwarded back to the Metals server.
+   *
+   * Metals may register commands in the client UIs like tree view node_modules
+   * that should be forwarded back to the Metals server if the client clicks
+   * on the UI elements.
+   */
+  EchoCommand: "metals-echo-command",
+  /** Focus on the window that lists all published diagnostics. */
+  FocusDiagnostics: "metals-diagnostics-focus",
+  /**
+   * Move the cursor focus to the provided location.
+   */
+  GotoLocation: "metals-goto-location",
+  /** Open a specific folder either in the same or new window */
+  OpenFolder: "metals-open-folder",
+  /**
+   * Notifies the client that the model has been updated and it
+   * should be refreshed (e.g. by resending code lens request)
+   */
+  RefreshModel: "metals-model-refresh",
+  /**
+   * Reload the contents of an open Doctor window, if any. Should be ignored if
+   * there is no open doctor window.
+   */
+  ReloadDoctor: "metals-doctor-reload",
+  /** Focus on a window displaying troubleshooting help from the Metals doctor. */
+  RunDoctor: "metals-doctor-run",
+  /**
+   * Command to trigger a debug session with Metals. Triggered by a code lens
+   * in the editor.
+   */
+  StartDebugSession: "metals-debug-session-start",
+  /** Command to run the codev via a code lens in the editor. */
+  StartRunSession: "metals-run-session-start",
+  /**
+   * Focus or remove focus on the output logs reported by the server via
+   * `window/logMessage`.
+   */
+  ToggleLogs: "metals-logs-toggle",
+} as const;
+
+export type ClientCommands = typeof ClientCommands;
diff --git a/src/interfaces/Extensions.ts b/src/interfaces/Extensions.ts
new file mode 100644
index 0000000..2130d1b
--- /dev/null
+++ b/src/interfaces/Extensions.ts
@@ -0,0 +1,68 @@
+import {
+  NotificationType,
+  ExecuteCommandParams,
+} from "vscode-languageserver-protocol";
+
+/**
+ * The Metals execute client command is sent from the server to the client to
+ * trigger an action inside the editor. This notification is a copy of the
+ * workspace/executeCommand except:
+ *
+ *  - execute client command is a notification, not a request
+ *  - execute client command is initiated from the server, not the client
+ *
+ *  - https://scalameta.org/metals/docs/editors/new-editor.html#metalsexecuteclientcommand
+ *
+ * All client commands can be found in the ClientCommands enum.
+ */
+export namespace ExecuteClientCommand {
+  export const type = new NotificationType<ExecuteCommandParams, void>(
+    "metals/executeClientCommand"
+  );
+}
+
+/**
+ * The Metals did focus notification is sent from the client to the server when the editor changes focus to a new text document. Unlike textDocument/didOpen, the did focus notification is sent even when the text document is already open.
+ *
+ * - https://scalameta.org/metals/docs/editors/new-editor.html#metalsdidfocustextdocument
+ */
+export namespace MetalsDidFocus {
+  export const type = new NotificationType<string, void>(
+    "metals/didFocusTextDocument"
+  );
+}
+
+/**
+ * The `metals/windowStateDidChange` notification is sent from the client to
+ * the server to indicate whether the editor application window is focused or
+ * not. When the editor window is not focused, Metals tries to avoid triggering
+ * expensive computation in the background such as compilation.
+ *
+ * - https://scalameta.org/metals/docs/editors/new-editor.html#metalswindowstatedidchange
+ */
+export namespace MetalsWindowStateDidChange {
+  export const type = new NotificationType<
+    MetalsWindowStateDidChangeParams,
+    void
+  >("metals/windowStateDidChange");
+}
+
+export interface MetalsWindowStateDidChangeParams {
+  /** If true, the editor application window is focused. False, otherwise. */
+  focused: boolean;
+}
+
+/**
+ * The  `metals/openWindow` params are used with the New Scala Project
+ * functionality. After the new project has been created, if the editor has the
+ * ability to open the project in a new window then these params are used with the
+ * the `metals-open-folder` command.
+ *
+ * - https://scalameta.org/metals/docs/editors/new-editor.html#metalsopenwindow
+ */
+export interface MetalsOpenWindowParams {
+  /** Location of the newly created project. */
+  uri: string;
+  /** Whether or not to open the project in a new window. */
+  openNewWindow: boolean;
+}
diff --git a/src/interfaces/MetalsInputBox.ts b/src/interfaces/MetalsInputBox.ts
new file mode 100644
index 0000000..49b36ed
--- /dev/null
+++ b/src/interfaces/MetalsInputBox.ts
@@ -0,0 +1,83 @@
+import { RequestType } from "vscode-languageserver-protocol";
+
+/**
+ * The Metals input box request is sent from the server to the client to
+ * let the user provide a string value for a given prompt. Unlike
+ * `window/showMessageRequest`, the `metals/inputBox` request allows the user
+ * to provide a custom response instead of picking a pre-selected value.
+ *
+ * - https://scalameta.org/metals/docs/editors/new-editor.html#metalsinputbox
+ */
+export namespace MetalsInputBox {
+  export const type = new RequestType<
+    InputBoxOptions,
+    MetalsInputBoxResult,
+    void,
+    void
+  >("metals/inputBox");
+
+  export const handleInput = function (
+    result: string | undefined
+  ): MetalsInputBoxResult {
+    if (result === undefined || result.trim() === "") {
+      return { cancelled: true };
+    } else {
+      return { value: result };
+    }
+  };
+}
+
+export interface MetalsInputBoxResult {
+  value?: string;
+  cancelled?: boolean;
+}
+
+/**
+ * The below is ported directly from VS Code:
+ *
+ * - https://code.visualstudio.com/api/references/vscode-api#InputBoxOptions
+ *
+ * This is managed in here since the Metals API for Input Boxes matches this
+ * exactly meaning that we rely on it both in the VS Code extension and also
+ * coc-metals. If the API changes, we'll have to chage it in Metals and in here.
+ */
+export interface InputBoxOptions {
+  /** * The value to prefill in the input box.  */
+  value?: string;
+  /** * Selection of the prefilled [`value`](#InputBoxOptions.value). Defined as tuple of two number where the * first is the inclusive start index and the second the exclusive end index. When `undefined` the whole * word will be selected, when empty (start equals end) only the cursor will be set, * otherwise the defined range will be selected.  */ valueSelection?: [
+    number,
+    number
+  ];
+
+  /**
+   * The text to display underneath the input box.
+   */
+  prompt?: string;
+
+  /**
+   * An optional string to show as place holder in the input box to guide the user what to type.
+   */
+  placeHolder?: string;
+
+  /**
+   * Set to `true` to show a password prompt that will not show the typed value.
+   */
+  password?: boolean;
+
+  /**
+   * Set to `true` to keep the input box open when focus moves to another part of the editor or to another window.
+   */
+  ignoreFocusOut?: boolean;
+
+  /**
+   * An optional function that will be called to validate input and to give a hint
+   * to the user.
+   *
+   * @param value The current value of the input box.
+   * @return A human readable string which is presented as diagnostic message.
+   * Return `undefined`, `null`, or the empty string when 'value' is valid.
+   */
+  validateInput?(
+    value: string
+  ): string | undefined | null | Thenable<string | undefined | null>;
+}
diff --git a/src/interfaces/MetalsQuickPick.ts b/src/interfaces/MetalsQuickPick.ts
new file mode 100644
index 0000000..d1cf48c
--- /dev/null
+++ b/src/interfaces/MetalsQuickPick.ts
@@ -0,0 +1,55 @@
+import { RequestType } from "vscode-languageserver-protocol";
+/**
+ * The Metals quick pick request is sent from the server to the client to let
+ * the user provide a string value by picking one out of a number of given
+ * options. It is similar to `window/showMessageRequest`, but the
+ * `metals/quickPick` request has richer parameters, that can be used to
+ * filter items to pick, like description and detail.
+ *
+ * - https://scalameta.org/metals/docs/editors/new-editor.html#metalsquickpick
+ */
+export namespace MetalsQuickPick {
+  export const type = new RequestType<
+    MetalsQuickPickParams,
+    MetalsQuickPickResult,
+    void,
+    void
+  >("metals/quickPick");
+}
+
+export interface MetalsQuickPickParams {
+  /** An array of items that can be selected from. */
+  items: MetalsQuickPickItem[];
+  /** An optional flag to include the description when filtering the picks. */
+  matchOnDescription?: boolean;
+  /** An optional flag to include the detail when filtering the picks. */
+  matchOnDetail?: boolean;
+  /**
+   * An optional string to show as place holder in the input box to guide the
+   * user what to pick on.
+   */
+  placeHolder?: string;
+  /**
+   * Set to `true` to keep the picker open when focus moves to another part of
+   * the editor or to another window.
+   */
+  ignoreFocusOut?: boolean;
+}
+
+export interface MetalsQuickPickResult {
+  itemId?: string;
+  cancelled?: boolean;
+}
+
+export interface MetalsQuickPickItem {
+  /** An id for this items that should be return as a result of the picking. */
+  id: string;
+  /** A human readable string which is rendered prominent. */
+  label: string;
+  /** A human readable string which is rendered less prominent. */
+  description?: string;
+  /** A human readable string which is rendered less prominent. */
+  detail?: string;
+  /** Always show this item. */
+  alwaysShow?: boolean;
+}
diff --git a/src/interfaces/MetalsSlowTask.ts b/src/interfaces/MetalsSlowTask.ts
new file mode 100644
index 0000000..cbbc864
--- /dev/null
+++ b/src/interfaces/MetalsSlowTask.ts
@@ -0,0 +1,40 @@
+import { RequestType } from "vscode-languageserver-protocol";
+
+/**
+ * The Metals slow task request is sent from the server to the client to notify
+ * the start of a long running process with unknown estimated total time.
+ * A cancel: true response from the client cancels the task. A $/cancelRequest
+ * request from the server indicates that the task has completed.
+ *
+ * - https://scalameta.org/metals/docs/editors/new-editor.html#metalsslowtask
+ */
+export namespace MetalsSlowTask {
+  export const type = new RequestType<
+    MetalsSlowTaskParams,
+    MetalsSlowTaskResult,
+    void,
+    void
+  >("metals/slowTask");
+}
+
+export interface MetalsSlowTaskParams {
+  /** The name of this slow task */
+  message: string;
+  /**
+   * If true, the log output from this task does not need to be displayed to the user.
+   *
+   * In VS Code, the Metals "Output channel" is not toggled when this flag is true.
+   */
+  quietLogs?: boolean;
+  /** Time that has elapsed since the begging of the task. */
+  secondsElapsed?: number;
+}
+
+export interface MetalsSlowTaskResult {
+  /**
+   * If true, cancel the running task.
+   * If false, the user dismissed the dialogue but want to
+   * continue running the task.
+   */
+  cancel: boolean;
+}
diff --git a/src/interfaces/MetalsStatus.ts b/src/interfaces/MetalsStatus.ts
new file mode 100644
index 0000000..5f43f89
--- /dev/null
+++ b/src/interfaces/MetalsStatus.ts
@@ -0,0 +1,29 @@
+import { NotificationType } from "vscode-languageserver-protocol";
+
+/**
+ * The Metals status notification is sent from the server to the client to
+ * notify about non-critical and non-actionable events that are happening in
+ * the server. Metals status notifications are a complement to
+ * `window/showMessage` and `window/logMessage`. Unlike `window/logMessage`,
+ * status notifications should always be visible in the user interface.
+ * Unlike `window/showMessage`, status notifications are not critical meaning
+ * that they should not demand too much attention from the user.
+ */
+export namespace MetalsStatus {
+  export const type = new NotificationType<MetalsStatusParams, void>(
+    "metals/status"
+  );
+}
+
+export interface MetalsStatusParams {
+  /** The text to display in the status bar. */
+  text: string;
+  /** If true, show the status bar. */
+  show?: boolean;
+  /** If true, hide the status bar. */
+  hide?: boolean;
+  /** If set, display this message when user hovers over the status bar. */
+  tooltip?: string;
+  /** If set, execute this command when the user clicks on the status bar item. */
+  command?: string;
+}
diff --git a/src/interfaces/ServerCommands.ts b/src/interfaces/ServerCommands.ts
new file mode 100644
index 0000000..72b9b71
--- /dev/null
+++ b/src/interfaces/ServerCommands.ts
@@ -0,0 +1,73 @@
+/**
+ * These are all of the server commands that Metals supports. Note that not support
+ * may vary based on the `InitializationSettings` the client sets.
+ *
+ *  - https://scalameta.org/metals/docs/editors/new-editor.html#metals-server-commands
+ */
+export const ServerCommands = {
+  /** Start the Ammonite build server. */
+  AmmoniteStart: "ammonite-start",
+  /** Stop the Ammonite build server. */
+  AmmoniteStop: "ammonite-stop",
+  /**
+   * Prompt the user to select a new build server to connect to.
+   *
+   * This command does nothing in the case there are less than two installed
+   * build servers on the computer.
+   */
+  BspSwitch: "bsp-switch",
+  /** Establish a new connection to the build server and reindex the workspace. */
+  BuildConnect: "build-connect",
+  /** Import the latest changes from the build. */
+  BuildImport: "build-import",
+  /**
+   * Unconditionally stop the current running Bloop server and start a new
+   * one using Bloop launcher.
+   */
+  BuildRestart: "build-restart",
+  /** Cancel the current ongoing compilation, if any. */
+  CancelCompilation: "compile-cancel",
+  /**
+   * Compile the current open files along with all build targets in this
+   * workspace that depend on those files.
+   *
+   * By default, Metals compiles only the current build target and its
+   * dependencies when saving a file. Run the cascade compile task to
+   * additionally compile the inverse dependencies of the current build target.
+   * For example, if you change the API in main sources and run cascade compile
+   * then it will also compile the test sources that depend on main.
+   */
+  CascadeCompile: "compile-cascade",
+  /** Recompile all build targets in this workspace. */
+  CleanCompile: "compile-clean",
+  /** Start debug adapter. */
+  DebugAdapterStart: "debug-adapter-start",
+  /** Open the Metals doctor to troubleshoot potential problems with the build. */
+  DoctorRun: "doctor-run",
+  /** Move the cursor to the definition of the argument symbol. */
+  Goto: "goto",
+  /** Jumps to the super method/field definition of a symbol. */
+  GotoSuperMethod: "goto-super-method",
+  /**
+   * Create and open a new Scala class, object, trait, package object, or
+   * worksheet.
+   */
+  NewScalaFile: "new-scala-file",
+  /** Creaet a new Scala project using one of the available g8 templates. */
+  NewScalaProject: "new-scala-project",
+  /** Reset a decision you made about a specific setting. */
+  ResetChoice: "reset-choice",
+  /** Walk all the files in the workspace and index where symbols are defined. */
+  SourcesScan: "sources-scan",
+  /**
+   * When user executes this command it will calculate inheritance hierarchy of
+   * a class that contains given method. Then it will filter out classes not
+   * overriding given method and a list using 'metalsQuickPick' will be
+   * displayed to which super method user would like to go to. Command has no
+   * effect on other symbols than method definition. QuickPick will show up
+   * only if more than one result is found.
+   */
+  SuperMethodHierarchy: "super-method-hierarchy",
+} as const;
+
+type ServerCommands = typeof ServerCommands;