feat(coding-agent): add message copy shortcut

packages/coding-agent/CHANGELOG.md

@@ -2,6 +2,10 @@
 
 ## [Unreleased]
 
+### Added
+
+- Added `Ctrl+X` to copy the last assistant message, or the selected message in `/tree`.
+
 ### Fixed
 
 - Fixed `/login amazon-bedrock` to prompt for and save a Bedrock API key instead of only displaying ambient AWS credential setup instructions.

packages/coding-agent/README.md

@@ -212,6 +212,7 @@ See `/hotkeys` for the full list. Customize via `~/.pi/agent/keybindings.json`.
 | Shift+Tab | Cycle thinking level |
 | Ctrl+O | Collapse/expand tool output |
 | Ctrl+T | Collapse/expand thinking blocks |
+| Ctrl+X | Copy the last assistant message |
 
 ### Message Queue
 
@@ -255,6 +256,7 @@ Use `/session` in interactive mode to see the current session ID before reusing
 
 - Search by typing, fold/unfold and jump between branches with Ctrl+←/Ctrl+→ or Alt+←/Alt+→, page with ←/→
 - Filter modes (Ctrl+O): default → no-tools → user-only → labeled-only → all
+- Press Ctrl+X to copy the selected message
 - Press Shift+L to label entries as bookmarks and Shift+T to toggle label timestamps
 
 **`/fork`** - Create a new session file from a previous user message on the active branch. Opens a selector, copies the active path up to that point, and places the selected prompt in the editor for modification.

packages/coding-agent/docs/keybindings.md

@@ -119,6 +119,7 @@ Modifier combinations: `ctrl+shift+x`, `alt+ctrl+x`, `ctrl+shift+alt+x`, `ctrl+1
 | Keybinding id | Default | Description |
 |--------|---------|-------------|
 | `app.tools.expand` | `ctrl+o` | Collapse or expand tool output |
+| `app.message.copy` | `ctrl+x` | Copy the last assistant message, or the selected message in `/tree` |
 | `app.message.followUp` | `alt+enter` | Queue follow-up message |
 | `app.message.dequeue` | `alt+up` | Restore queued messages to editor |
 

packages/coding-agent/docs/usage.md

@@ -22,6 +22,7 @@ The editor can be replaced temporarily by built-in UI such as `/settings` or by
 | File reference | Type `@` to fuzzy-search project files |
 | Path completion | Press Tab to complete paths |
 | Multi-line input | Shift+Enter, or Ctrl+Enter on Windows Terminal |
+| Copy response | Ctrl+X copies the last assistant message; in `/tree`, it copies the selected message |
 | Images | Paste with Ctrl+V, Alt+V on Windows, or drag into the terminal |
 | Shell command | `!command` runs and sends output to the model |
 | Hidden shell command | `!!command` runs without sending output to the model |

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

@@ -78,6 +78,7 @@ const RESERVED_KEYBINDINGS_FOR_EXTENSION_CONFLICTS = [
 	"app.tools.expand",
 	"app.thinking.toggle",
 	"app.editor.external",
+	"app.message.copy",
 	"app.message.followUp",
 	"tui.input.submit",
 	"tui.select.confirm",

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

@@ -23,6 +23,7 @@ export interface AppKeybindings {
 	"app.thinking.toggle": true;
 	"app.session.toggleNamedFilter": true;
 	"app.editor.external": true;
+	"app.message.copy": true;
 	"app.message.followUp": true;
 	"app.message.dequeue": true;
 	"app.clipboard.pasteImage": true;
@@ -95,6 +96,10 @@ export const KEYBINDINGS = {
 		defaultKeys: "ctrl+g",
 		description: "Open external editor",
 	},
+	"app.message.copy": {
+		defaultKeys: "ctrl+x",
+		description: "Copy message to clipboard",
+	},
 	"app.message.followUp": {
 		defaultKeys: "alt+enter",
 		description: "Queue follow-up message",
@@ -112,11 +117,11 @@ export const KEYBINDINGS = {
 	"app.session.fork": { defaultKeys: [], description: "Fork current session" },
 	"app.session.resume": { defaultKeys: [], description: "Resume a session" },
 	"app.tree.foldOrUp": {
-		defaultKeys: ["ctrl+left", "alt+left"],
+		defaultKeys: process.platform === "darwin" ? ["alt+left", "ctrl+left"] : ["ctrl+left", "alt+left"],
 		description: "Fold tree branch or move up",
 	},
 	"app.tree.unfoldOrDown": {
-		defaultKeys: ["ctrl+right", "alt+right"],
+		defaultKeys: process.platform === "darwin" ? ["alt+right", "ctrl+right"] : ["ctrl+right", "alt+right"],
 		description: "Unfold tree branch or move down",
 	},
 	"app.tree.editLabel": {

packages/coding-agent/src/modes/interactive/components/tree-selector.ts

@@ -122,6 +122,7 @@ class TreeList implements Component {
 
 	public onSelect?: (entryId: string) => void;
 	public onCancel?: () => void;
+	public onCopy?: (text: string | undefined) => void;
 	public onLabelEdit?: (entryId: string, currentLabel: string | undefined) => void;
 
 	constructor(
@@ -623,6 +624,11 @@ class TreeList implements Component {
 		return this.filteredNodes[this.selectedIndex]?.node;
 	}
 
+	copySelected(): void {
+		const node = this.getSelectedNode();
+		this.onCopy?.(node ? this.getEntryCopyText(node) : undefined);
+	}
+
 	updateNodeLabel(entryId: string, label: string | undefined, labelTimestamp?: string): void {
 		for (const flatNode of this.flatNodes) {
 			if (flatNode.node.entry.id === entryId) {
@@ -871,19 +877,49 @@ class TreeList implements Component {
 	}
 
 	private extractContent(content: unknown): string {
-		const maxLen = 200;
-		if (typeof content === "string") return content.slice(0, maxLen);
-		if (Array.isArray(content)) {
-			let result = "";
-			for (const c of content) {
-				if (typeof c === "object" && c !== null && "type" in c && c.type === "text") {
-					result += (c as { text: string }).text;
-					if (result.length >= maxLen) return result.slice(0, maxLen);
-				}
+		return this.extractFullContent(content).slice(0, 200);
+	}
+
+	private extractFullContent(content: unknown): string {
+		if (typeof content === "string") return content;
+		if (!Array.isArray(content)) return "";
+
+		let result = "";
+		for (const block of content) {
+			if (typeof block === "object" && block !== null && "type" in block && block.type === "text") {
+				result += (block as { text: string }).text;
 			}
-			return result;
 		}
-		return "";
+		return result;
+	}
+
+	private getEntryCopyText(node: SessionTreeNode): string | undefined {
+		const entry = node.entry;
+		let text: string | undefined;
+
+		switch (entry.type) {
+			case "message":
+				if (entry.message.role === "bashExecution") {
+					text = entry.message.command;
+				} else if ("content" in entry.message) {
+					text = this.extractFullContent(entry.message.content);
+					if (!text && entry.message.role === "assistant") {
+						text = entry.message.errorMessage;
+					}
+				}
+				break;
+			case "custom_message":
+				text = this.extractFullContent(entry.content);
+				break;
+			case "compaction":
+				text = entry.summary;
+				break;
+			case "branch_summary":
+				text = entry.summary;
+				break;
+		}
+
+		return text?.trim() ? text : undefined;
 	}
 
 	private hasTextContent(content: unknown): boolean {
@@ -990,6 +1026,8 @@ class TreeList implements Component {
 			if (selected && this.onSelect) {
 				this.onSelect(selected.node.entry.id);
 			}
+		} else if (kb.matches(keyData, "app.message.copy")) {
+			this.copySelected();
 		} else if (kb.matches(keyData, "tui.select.cancel")) {
 			if (this.searchQuery) {
 				this.searchQuery = "";
@@ -1180,6 +1218,7 @@ const TREE_HELP_ITEMS: Array<{ keys: Keybinding[]; label: string; labelFirst?: b
 	{ keys: ["tui.select.up", "tui.select.down"], label: "move" },
 	{ keys: ["tui.editor.cursorLeft", "tui.editor.cursorRight"], label: "page" },
 	{ keys: ["app.tree.foldOrUp", "app.tree.unfoldOrDown"], label: "branch" },
+	{ keys: ["app.message.copy"], label: "copy" },
 	{ keys: ["app.tree.editLabel"], label: "label" },
 	{ keys: ["app.tree.toggleLabelTimestamp"], label: "label time" },
 	{
@@ -1292,6 +1331,7 @@ export class TreeSelectorComponent extends Container implements Focusable {
 	private labelInputContainer: Container;
 	private treeContainer: Container;
 	private onLabelChangeCallback?: (entryId: string, label: string | undefined) => void;
+	public onCopy?: (text: string | undefined) => void;
 
 	// Focusable implementation - propagate to labelInput when active for IME cursor positioning
 	private _focused = false;
@@ -1324,6 +1364,7 @@ export class TreeSelectorComponent extends Container implements Focusable {
 		this.treeList = new TreeList(tree, currentLeafId, maxVisibleLines, initialSelectedId, initialFilterMode);
 		this.treeList.onSelect = onSelect;
 		this.treeList.onCancel = onCancel;
+		this.treeList.onCopy = (text) => this.onCopy?.(text);
 		this.treeList.onLabelEdit = (entryId, currentLabel) => this.showLabelInput(entryId, currentLabel);
 
 		this.treeContainer = new Container();

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

@@ -2583,6 +2583,7 @@ export class InteractiveMode {
 		this.defaultEditor.onAction("app.tools.expand", () => this.toggleToolOutputExpansion());
 		this.defaultEditor.onAction("app.thinking.toggle", () => this.toggleThinkingBlockVisibility());
 		this.defaultEditor.onAction("app.editor.external", () => this.openExternalEditor());
+		this.defaultEditor.onAction("app.message.copy", () => void this.handleCopyCommand());
 		this.defaultEditor.onAction("app.message.followUp", () => this.handleFollowUp());
 		this.defaultEditor.onAction("app.message.dequeue", () => this.handleDequeue());
 		this.defaultEditor.onAction("app.session.new", () => this.handleClearCommand());
@@ -4708,6 +4709,18 @@ export class InteractiveMode {
 				initialSelectedId,
 				initialFilterMode,
 			);
+			selector.onCopy = async (text) => {
+				if (!text) {
+					this.showError("Selected entry has no text to copy");
+					return;
+				}
+				try {
+					await copyToClipboard(text);
+					this.showStatus("Copied selected message to clipboard");
+				} catch (error) {
+					this.showError(error instanceof Error ? error.message : String(error));
+				}
+			};
 			return { component: selector, focus: selector };
 		});
 	}
@@ -5735,6 +5748,7 @@ export class InteractiveMode {
 		const toggleThinking = this.getAppKeyDisplay("app.thinking.toggle");
 		const externalEditor = this.getAppKeyDisplay("app.editor.external");
 		const cycleModelBackward = this.getAppKeyDisplay("app.model.cycleBackward");
+		const copyMessage = this.getAppKeyDisplay("app.message.copy");
 		const followUp = this.getAppKeyDisplay("app.message.followUp");
 		const dequeue = this.getAppKeyDisplay("app.message.dequeue");
 		const pasteImage = this.getAppKeyDisplay("app.clipboard.pasteImage");
@@ -5778,6 +5792,7 @@ export class InteractiveMode {
 | \`${expandTools}\` | Toggle tool output expansion |
 | \`${toggleThinking}\` | Toggle thinking block visibility |
 | \`${externalEditor}\` | Edit message in external editor |
+| \`${copyMessage}\` | Copy last assistant message |
 | \`${followUp}\` | Queue follow-up message |
 | \`${dequeue}\` | Restore queued messages |
 | \`${pasteImage}\` | Paste image from clipboard |

packages/coding-agent/test/tree-selector.test.ts

@@ -264,6 +264,7 @@ describe("TreeSelectorComponent", () => {
 			const plainLines = selector.render(30).map(stripVTControlCharacters);
 			const plain = plainLines.join("\n");
 			expect(plain).toContain("branch");
+			expect(plain).toContain("copy");
 			expect(plain).toContain("filters");
 			expect(plain).toContain("cycle");
 			expect(plain).toContain("label time");
@@ -272,6 +273,28 @@ describe("TreeSelectorComponent", () => {
 		});
 	});
 
+	describe("copy", () => {
+		test("copies the full selected message with ctrl+x", () => {
+			const message = `${"long message ".repeat(30)}\nsecond line`;
+			const tree = buildTree([userMessage("user-1", null, "hello"), assistantMessage("asst-1", "user-1", message)]);
+			const selector = new TreeSelectorComponent(
+				tree,
+				"asst-1",
+				24,
+				() => {},
+				() => {},
+			);
+			let copied: string | undefined;
+			selector.onCopy = (text) => {
+				copied = text;
+			};
+
+			selector.handleInput("\x18");
+
+			expect(copied).toBe(message);
+		});
+	});
+
 	describe("label timestamps", () => {
 		test("toggles label timestamps for labeled nodes", () => {
 			const entries = [userMessage("user-1", null, "hello"), assistantMessage("asst-1", "user-1", "hi")];