diff --git a/src/vs/vscode.proposed.d.ts b/src/vs/vscode.proposed.d.ts
index e8d0f99c563..315b263c9f5 100644
--- a/src/vs/vscode.proposed.d.ts
+++ b/src/vs/vscode.proposed.d.ts
@@ -888,13 +888,39 @@ declare module 'vscode' {
 
 	//#region Terminal
 
+	/**
+	 * An [event](#Event) which fires when a [Terminal](#Terminal)'s dimensions change.
+	 */
+	export interface TerminalDimensionsChangeEvent {
+		/**
+		 * The [terminal](#Terminal) for which the dimensions have changed.
+		 */
+		readonly terminal: Terminal;
+		/**
+		 * The new value for the [terminal's dimensions](#Terminal.dimensions).
+		 */
+		readonly dimensions: TerminalDimensions;
+	}
+
+	namespace window {
+		/**
+		 * An event which fires when the [dimensions](#Terminal.dimensions) of the terminal change.
+		 */
+		export const onDidChangeTerminalDimensions: Event<TerminalDimensionsChangeEvent>;
+	}
+
 	export interface Terminal {
+		/**
+		 * The current dimensions of the terminal.
+		 */
+		readonly dimensions: TerminalDimensions;
+
 		/**
 		 * Fires when the terminal's pty slave pseudo-device is written to. In other words, this
 		 * provides access to the raw data stream from the process running within the terminal,
 		 * including VT sequences.
 		 */
-		onDidWriteData: Event<string>;
+		readonly onDidWriteData: Event<string>;
 	}
 
 	/**
diff --git a/src/vs/workbench/api/node/extHost.api.impl.ts b/src/vs/workbench/api/node/extHost.api.impl.ts
index 59ecf348f91..f6d2526d4b4 100644
--- a/src/vs/workbench/api/node/extHost.api.impl.ts
+++ b/src/vs/workbench/api/node/extHost.api.impl.ts
@@ -479,9 +479,9 @@ export function createApiFactory(
 				}
 				return extHostTerminalService.createTerminal(<string>nameOrOptions, shellPath, shellArgs);
 			},
-			createTerminalRenderer: proposedApiFunction(extension, (name: string) => {
+			createTerminalRenderer(name: string): vscode.TerminalRenderer {
 				return extHostTerminalService.createTerminalRenderer(name);
-			}),
+			},
 			registerTreeDataProvider(viewId: string, treeDataProvider: vscode.TreeDataProvider<any>): vscode.Disposable {
 				return extHostTreeViews.registerTreeDataProvider(viewId, treeDataProvider, extension);
 			},