Add shell commands without context contribution (!! prefix)

Use !!command to execute bash commands that are shown in the TUI and
saved to session history but excluded from LLM context, compaction
summaries, and branch summaries.

- Add excludeFromContext field to BashExecutionMessage
- Filter excluded messages in convertToLlm()
- Parse !! prefix in interactive mode
- Use dim border color for excluded commands

fixes #414

packages/coding-agent/src/core/agent-session.ts

@@ -1395,8 +1395,13 @@ export class AgentSession {
 	 * Adds result to agent context and session.
 	 * @param command The bash command to execute
 	 * @param onChunk Optional streaming callback for output
+	 * @param options.excludeFromContext If true, command output won't be sent to LLM (!! prefix)
 	 */
-	async executeBash(command: string, onChunk?: (chunk: string) => void): Promise<BashResult> {
+	async executeBash(
+		command: string,
+		onChunk?: (chunk: string) => void,
+		options?: { excludeFromContext?: boolean },
+	): Promise<BashResult> {
 		this._bashAbortController = new AbortController();
 
 		try {
@@ -1415,6 +1420,7 @@ export class AgentSession {
 				truncated: result.truncated,
 				fullOutputPath: result.fullOutputPath,
 				timestamp: Date.now(),
+				excludeFromContext: options?.excludeFromContext,
 			};
 
 			// If agent is streaming, defer adding to avoid breaking tool_use/tool_result ordering

packages/coding-agent/src/core/messages.ts

@@ -35,6 +35,8 @@ export interface BashExecutionMessage {
 	truncated: boolean;
 	fullOutputPath?: string;
 	timestamp: number;
+	/** If true, this message is excluded from LLM context (!! prefix) */
+	excludeFromContext?: boolean;
 }
 
 /**
@@ -148,6 +150,10 @@ export function convertToLlm(messages: AgentMessage[]): Message[] {
 		.map((m): Message | undefined => {
 			switch (m.role) {
 				case "bashExecution":
+					// Skip messages excluded from context (!! prefix)
+					if (m.excludeFromContext) {
+						return undefined;
+					}
 					return {
 						role: "user",
 						content: [{ type: "text", text: bashExecutionToText(m) }],

packages/coding-agent/src/modes/interactive/components/bash-execution.ts

@@ -29,12 +29,14 @@ export class BashExecutionComponent extends Container {
 	private contentContainer: Container;
 	private ui: TUI;
 
-	constructor(command: string, ui: TUI) {
+	constructor(command: string, ui: TUI, excludeFromContext = false) {
 		super();
 		this.command = command;
 		this.ui = ui;
 
-		const borderColor = (str: string) => theme.fg("bashMode", str);
+		// Use dim border for excluded-from-context commands (!! prefix)
+		const colorKey = excludeFromContext ? "dim" : "bashMode";
+		const borderColor = (str: string) => theme.fg(colorKey, str);
 
 		// Add spacer
 		this.addChild(new Spacer(1));
@@ -47,13 +49,13 @@ export class BashExecutionComponent extends Container {
 		this.addChild(this.contentContainer);
 
 		// Command header
-		const header = new Text(theme.fg("bashMode", theme.bold(`$ ${command}`)), 1, 0);
+		const header = new Text(theme.fg(colorKey, theme.bold(`$ ${command}`)), 1, 0);
 		this.contentContainer.addChild(header);
 
 		// Loader
 		this.loader = new Loader(
 			ui,
-			(spinner) => theme.fg("bashMode", spinner),
+			(spinner) => theme.fg(colorKey, spinner),
 			(text) => theme.fg("muted", text),
 			"Running... (esc to cancel)",
 		);

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

@@ -892,9 +892,10 @@ export class InteractiveMode {
 				return;
 			}
 
-			// Handle bash command
+			// Handle bash command (! for normal, !! for excluded from context)
 			if (text.startsWith("!")) {
-				const command = text.slice(1).trim();
+				const isExcluded = text.startsWith("!!");
+				const command = isExcluded ? text.slice(2).trim() : text.slice(1).trim();
 				if (command) {
 					if (this.session.isBashRunning) {
 						this.showWarning("A bash command is already running. Press Esc to cancel it first.");
@@ -902,7 +903,7 @@ export class InteractiveMode {
 						return;
 					}
 					this.editor.addToHistory(text);
-					await this.handleBashCommand(command);
+					await this.handleBashCommand(command, isExcluded);
 					this.isBashMode = false;
 					this.updateEditorBorderColor();
 					return;
@@ -1250,7 +1251,7 @@ export class InteractiveMode {
 	private addMessageToChat(message: AgentMessage, options?: { populateHistory?: boolean }): void {
 		switch (message.role) {
 			case "bashExecution": {
-				const component = new BashExecutionComponent(message.command, this.ui);
+				const component = new BashExecutionComponent(message.command, this.ui, message.excludeFromContext);
 				if (message.output) {
 					component.appendOutput(message.output);
 				}
@@ -2362,9 +2363,9 @@ export class InteractiveMode {
 		this.ui.requestRender();
 	}
 
-	private async handleBashCommand(command: string): Promise<void> {
+	private async handleBashCommand(command: string, excludeFromContext = false): Promise<void> {
 		const isDeferred = this.session.isStreaming;
-		this.bashComponent = new BashExecutionComponent(command, this.ui);
+		this.bashComponent = new BashExecutionComponent(command, this.ui, excludeFromContext);
 
 		if (isDeferred) {
 			// Show in pending area when agent is streaming
@@ -2377,12 +2378,16 @@ export class InteractiveMode {
 		this.ui.requestRender();
 
 		try {
-			const result = await this.session.executeBash(command, (chunk) => {
-				if (this.bashComponent) {
-					this.bashComponent.appendOutput(chunk);
-					this.ui.requestRender();
-				}
-			});
+			const result = await this.session.executeBash(
+				command,
+				(chunk) => {
+					if (this.bashComponent) {
+						this.bashComponent.appendOutput(chunk);
+						this.ui.requestRender();
+					}
+				},
+				{ excludeFromContext },
+			);
 
 			if (this.bashComponent) {
 				this.bashComponent.setComplete(