feat: add terminal input hook for extensions

packages/coding-agent/src/core/extensions/index.ts

@@ -123,6 +123,7 @@ export type {
 	SetLabelHandler,
 	SetModelHandler,
 	SetThinkingLevelHandler,
+	TerminalInputHandler,
 	// Events - Tool
 	ToolCallEvent,
 	ToolCallEventResult,

packages/coding-agent/src/core/extensions/runner.ts

@@ -170,6 +170,7 @@ const noOpUIContext: ExtensionUIContext = {
 	confirm: async () => false,
 	input: async () => undefined,
 	notify: () => {},
+	onTerminalInput: () => () => {},
 	setStatus: () => {},
 	setWorkingMessage: () => {},
 	setWidget: () => {},

packages/coding-agent/src/core/extensions/types.ts

@@ -97,6 +97,9 @@ export interface ExtensionWidgetOptions {
 	placement?: WidgetPlacement;
 }
 
+/** Raw terminal input listener for extensions. */
+export type TerminalInputHandler = (data: string) => { consume?: boolean; data?: string } | undefined;
+
 /**
  * UI context for extensions to request interactive UI.
  * Each mode (interactive, RPC, print) provides its own implementation.
@@ -114,6 +117,9 @@ export interface ExtensionUIContext {
 	/** Show a notification to the user. */
 	notify(message: string, type?: "info" | "warning" | "error"): void;
 
+	/** Listen to raw terminal input (interactive mode only). Returns an unsubscribe function. */
+	onTerminalInput(handler: TerminalInputHandler): () => void;
+
 	/** Set status text in the footer/status bar. Pass undefined to clear. */
 	setStatus(key: string, text: string | undefined): void;
 

packages/coding-agent/src/index.ts

@@ -100,6 +100,7 @@ export type {
 	SlashCommandInfo,
 	SlashCommandLocation,
 	SlashCommandSource,
+	TerminalInputHandler,
 	ToolCallEvent,
 	ToolDefinition,
 	ToolInfo,

packages/coding-agent/src/modes/interactive/interactive-mode.ts

@@ -1368,6 +1368,7 @@ export class InteractiveMode {
 			confirm: (title, message, opts) => this.showExtensionConfirm(title, message, opts),
 			input: (title, placeholder, opts) => this.showExtensionInput(title, placeholder, opts),
 			notify: (message, type) => this.showExtensionNotify(message, type),
+			onTerminalInput: (handler) => this.ui.addInputListener(handler),
 			setStatus: (key, text) => this.setExtensionStatus(key, text),
 			setWorkingMessage: (message) => {
 				if (this.loadingAnimation) {

packages/coding-agent/src/modes/rpc/rpc-mode.ts

@@ -144,6 +144,11 @@ export async function runRpcMode(session: AgentSession): Promise<never> {
 			} as RpcExtensionUIRequest);
 		},
 
+		onTerminalInput(): () => void {
+			// Raw terminal input not supported in RPC mode
+			return () => {};
+		},
+
 		setStatus(key: string, text: string | undefined): void {
 			// Fire and forget - no response needed
 			output({

packages/tui/src/tui.ts

@@ -39,6 +39,9 @@ export interface Component {
 	invalidate(): void;
 }
 
+type InputListenerResult = { consume?: boolean; data?: string } | undefined;
+type InputListener = (data: string) => InputListenerResult;
+
 /**
  * Interface for components that can receive focus and display a hardware cursor.
  * When focused, the component should emit CURSOR_MARKER at the cursor position
@@ -200,6 +203,7 @@ export class TUI extends Container {
 	private previousLines: string[] = [];
 	private previousWidth = 0;
 	private focusedComponent: Component | null = null;
+	private inputListeners = new Set<InputListener>();
 
 	/** Global callback for debug key (Shift+Ctrl+D). Called before input is forwarded to focused component. */
 	public onDebug?: () => void;
@@ -377,6 +381,17 @@ export class TUI extends Container {
 		this.requestRender();
 	}
 
+	addInputListener(listener: InputListener): () => void {
+		this.inputListeners.add(listener);
+		return () => {
+			this.inputListeners.delete(listener);
+		};
+	}
+
+	removeInputListener(listener: InputListener): void {
+		this.inputListeners.delete(listener);
+	}
+
 	private queryCellSize(): void {
 		// Only query if terminal supports images (cell size is only used for image rendering)
 		if (!getCapabilities().images) {
@@ -424,6 +439,23 @@ export class TUI extends Container {
 	}
 
 	private handleInput(data: string): void {
+		if (this.inputListeners.size > 0) {
+			let current = data;
+			for (const listener of this.inputListeners) {
+				const result = listener(current);
+				if (result?.consume) {
+					return;
+				}
+				if (result?.data !== undefined) {
+					current = result.data;
+				}
+			}
+			if (current.length === 0) {
+				return;
+			}
+			data = current;
+		}
+
 		// If we're waiting for cell size response, buffer input and parse
 		if (this.cellSizeQueryPending) {
 			this.inputBuffer += data;