diff --git a/site/src/pages/AgentsPage/components/ChatMessageInput/ChatMessageInput.tsx b/site/src/pages/AgentsPage/components/ChatMessageInput/ChatMessageInput.tsx
index dcf643bf11..582078bfa3 100644
--- a/site/src/pages/AgentsPage/components/ChatMessageInput/ChatMessageInput.tsx
+++ b/site/src/pages/AgentsPage/components/ChatMessageInput/ChatMessageInput.tsx
@@ -41,6 +41,7 @@ import {
 	$createFileReferenceNode,
 	FileReferenceNode,
 } from "./FileReferenceNode";
+import { IOSBackspacePlugin } from "./iosBackspace";
 import {
 	createPasteFile,
 	getPasteDataTransfer,
@@ -376,7 +377,7 @@ const ValueSyncPlugin: FC<{
 				editor.setEditorState(parsed);
 				return;
 			} catch {
-				// Malformed state — fall through to plain-text path.
+				// Malformed state, fall through to plain-text path.
 			}
 		}
 
@@ -736,6 +737,7 @@ const ChatMessageInput = ({
 					onEnter={disabled ? undefined : onEnter}
 					sendShortcut={sendShortcut}
 				/>
+				<IOSBackspacePlugin />
 				<ContentChangePlugin onChange={onChange} />
 				<ValueSyncPlugin
 					initialValue={initialValue}
diff --git a/site/src/pages/AgentsPage/components/ChatMessageInput/iosBackspace.test.ts b/site/src/pages/AgentsPage/components/ChatMessageInput/iosBackspace.test.ts
new file mode 100644
index 0000000000..76f6429542
--- /dev/null
+++ b/site/src/pages/AgentsPage/components/ChatMessageInput/iosBackspace.test.ts
@@ -0,0 +1,299 @@
+import {
+	$createParagraphNode,
+	$createRangeSelection,
+	$createTextNode,
+	$getRoot,
+	$getSelection,
+	$setSelection,
+	COMMAND_PRIORITY_HIGH,
+	createEditor,
+	DELETE_CHARACTER_COMMAND,
+	KEY_BACKSPACE_COMMAND,
+} from "lexical";
+import { describe, expect, it } from "vitest";
+import {
+	$createFileReferenceNode,
+	FileReferenceNode,
+} from "./FileReferenceNode";
+import {
+	$shouldUseNativeBackspace,
+	registerIOSBackspaceCommand,
+} from "./iosBackspace";
+
+function readBackspaceDecision(setup: () => void) {
+	const editor = createEditor({
+		namespace: "ios-backspace-test",
+		nodes: [FileReferenceNode],
+		onError: (error) => {
+			throw error;
+		},
+	});
+	let result = false;
+
+	editor.update(
+		() => {
+			setup();
+			result = $shouldUseNativeBackspace($getSelection());
+		},
+		{ discrete: true },
+	);
+
+	return result;
+}
+
+describe("$shouldUseNativeBackspace", () => {
+	it("allows native deletion from plain text selections", () => {
+		const result = readBackspaceDecision(() => {
+			const root = $getRoot();
+			const paragraph = $createParagraphNode();
+			const text = $createTextNode("hello");
+			root.append(paragraph);
+			paragraph.append(text);
+			text.select(5, 5);
+		});
+
+		expect(result).toBe(true);
+	});
+
+	it("allows native deletion when a file reference precedes a mid-text caret", () => {
+		const result = readBackspaceDecision(() => {
+			const root = $getRoot();
+			const paragraph = $createParagraphNode();
+			const fileReference = $createFileReferenceNode(
+				"main.go",
+				1,
+				1,
+				"package main",
+			);
+			const text = $createTextNode("hello");
+			root.append(paragraph);
+			paragraph.append(fileReference, text);
+			text.select(3, 3);
+		});
+
+		expect(result).toBe(true);
+	});
+
+	it("keeps Lexical deletion when backspace would hit a file reference", () => {
+		const result = readBackspaceDecision(() => {
+			const root = $getRoot();
+			const paragraph = $createParagraphNode();
+			const fileReference = $createFileReferenceNode(
+				"main.go",
+				1,
+				1,
+				"package main",
+			);
+			const text = $createTextNode("hello");
+			root.append(paragraph);
+			paragraph.append(fileReference, text);
+			text.select(0, 0);
+		});
+
+		expect(result).toBe(false);
+	});
+
+	it("keeps Lexical deletion when backspace would hit a file reference in the previous paragraph", () => {
+		const result = readBackspaceDecision(() => {
+			const root = $getRoot();
+			const previousParagraph = $createParagraphNode();
+			const currentParagraph = $createParagraphNode();
+			const fileReference = $createFileReferenceNode(
+				"main.go",
+				1,
+				1,
+				"package main",
+			);
+			const text = $createTextNode("hello");
+			root.append(previousParagraph, currentParagraph);
+			previousParagraph.append(fileReference);
+			currentParagraph.append(text);
+			text.select(0, 0);
+		});
+
+		expect(result).toBe(false);
+	});
+
+	it("keeps Lexical deletion when the selection contains a file reference", () => {
+		const result = readBackspaceDecision(() => {
+			const root = $getRoot();
+			const paragraph = $createParagraphNode();
+			const before = $createTextNode("before");
+			const fileReference = $createFileReferenceNode(
+				"main.go",
+				1,
+				1,
+				"package main",
+			);
+			const after = $createTextNode("after");
+			root.append(paragraph);
+			paragraph.append(before, fileReference, after);
+
+			const selection = $createRangeSelection();
+			selection.anchor.set(before.getKey(), 0, "text");
+			selection.focus.set(after.getKey(), 5, "text");
+			$setSelection(selection);
+		});
+
+		expect(result).toBe(false);
+	});
+
+	it("keeps Lexical deletion for element anchor at offset 0 after a file reference paragraph", () => {
+		const result = readBackspaceDecision(() => {
+			const root = $getRoot();
+			const firstParagraph = $createParagraphNode();
+			const secondParagraph = $createParagraphNode();
+			const fileReference = $createFileReferenceNode(
+				"main.go",
+				1,
+				1,
+				"package main",
+			);
+			root.append(firstParagraph, secondParagraph);
+			firstParagraph.append(fileReference);
+			secondParagraph.selectStart();
+		});
+
+		expect(result).toBe(false);
+	});
+
+	it("keeps Lexical deletion for element anchor at offset > 0 next to a file reference child", () => {
+		const result = readBackspaceDecision(() => {
+			const root = $getRoot();
+			const paragraph = $createParagraphNode();
+			const fileReference = $createFileReferenceNode(
+				"main.go",
+				1,
+				1,
+				"package main",
+			);
+			const text = $createTextNode("hello");
+			root.append(paragraph);
+			paragraph.append(fileReference, text);
+			paragraph.select(1, 1);
+		});
+
+		expect(result).toBe(false);
+	});
+});
+
+describe("registerIOSBackspaceCommand", () => {
+	it("falls through when native backspace is disabled", () => {
+		const editor = createEditor({
+			namespace: "ios-backspace-command-disabled-test",
+			onError: (error) => {
+				throw error;
+			},
+		});
+		let deleteCharacterDispatched = false;
+
+		registerIOSBackspaceCommand(editor, false);
+		editor.registerCommand(
+			DELETE_CHARACTER_COMMAND,
+			() => {
+				deleteCharacterDispatched = true;
+				return true;
+			},
+			COMMAND_PRIORITY_HIGH,
+		);
+
+		const event = new KeyboardEvent("keydown", {
+			cancelable: true,
+			key: "Backspace",
+		});
+
+		expect(editor.dispatchCommand(KEY_BACKSPACE_COMMAND, event)).toBe(false);
+		expect(event.defaultPrevented).toBe(false);
+		expect(deleteCharacterDispatched).toBe(false);
+	});
+
+	it("prevents default and dispatches Lexical deletion near file references", () => {
+		const editor = createEditor({
+			namespace: "ios-backspace-command-test",
+			nodes: [FileReferenceNode],
+			onError: (error) => {
+				throw error;
+			},
+		});
+		let deleteCharacterDirection: boolean | undefined;
+
+		registerIOSBackspaceCommand(editor, true);
+		editor.registerCommand(
+			DELETE_CHARACTER_COMMAND,
+			(isBackward) => {
+				deleteCharacterDirection = isBackward;
+				return true;
+			},
+			COMMAND_PRIORITY_HIGH,
+		);
+
+		editor.update(
+			() => {
+				const root = $getRoot();
+				const paragraph = $createParagraphNode();
+				const fileReference = $createFileReferenceNode(
+					"main.go",
+					1,
+					1,
+					"package main",
+				);
+				const text = $createTextNode("hello");
+				root.append(paragraph);
+				paragraph.append(fileReference, text);
+				text.select(0, 0);
+			},
+			{ discrete: true },
+		);
+
+		const event = new KeyboardEvent("keydown", {
+			cancelable: true,
+			key: "Backspace",
+		});
+
+		expect(editor.dispatchCommand(KEY_BACKSPACE_COMMAND, event)).toBe(true);
+		expect(event.defaultPrevented).toBe(true);
+		expect(deleteCharacterDirection).toBe(true);
+	});
+
+	it("does not prevent default for plain text iOS backspace", () => {
+		const editor = createEditor({
+			namespace: "ios-backspace-command-test",
+			nodes: [FileReferenceNode],
+			onError: (error) => {
+				throw error;
+			},
+		});
+		let deleteCharacterDirection: boolean | undefined;
+
+		registerIOSBackspaceCommand(editor, true);
+		editor.registerCommand(
+			DELETE_CHARACTER_COMMAND,
+			(isBackward) => {
+				deleteCharacterDirection = isBackward;
+				return true;
+			},
+			COMMAND_PRIORITY_HIGH,
+		);
+
+		editor.update(
+			() => {
+				const root = $getRoot();
+				const paragraph = $createParagraphNode();
+				const text = $createTextNode("hello");
+				root.append(paragraph);
+				paragraph.append(text);
+				text.select(5, 5);
+			},
+			{ discrete: true },
+		);
+
+		const event = new KeyboardEvent("keydown", {
+			cancelable: true,
+			key: "Backspace",
+		});
+
+		expect(editor.dispatchCommand(KEY_BACKSPACE_COMMAND, event)).toBe(true);
+		expect(event.defaultPrevented).toBe(false);
+		expect(deleteCharacterDirection).toBeUndefined();
+	});
+});
diff --git a/site/src/pages/AgentsPage/components/ChatMessageInput/iosBackspace.tsx b/site/src/pages/AgentsPage/components/ChatMessageInput/iosBackspace.tsx
new file mode 100644
index 0000000000..80de0f93ad
--- /dev/null
+++ b/site/src/pages/AgentsPage/components/ChatMessageInput/iosBackspace.tsx
@@ -0,0 +1,85 @@
+import { useLexicalComposerContext } from "@lexical/react/LexicalComposerContext";
+import { CAN_USE_BEFORE_INPUT, IS_IOS } from "@lexical/utils";
+import {
+	$getSelection,
+	$isDecoratorNode,
+	$isElementNode,
+	$isRangeSelection,
+	type BaseSelection,
+	COMMAND_PRIORITY_HIGH,
+	DELETE_CHARACTER_COMMAND,
+	KEY_BACKSPACE_COMMAND,
+	type LexicalEditor,
+	type LexicalNode,
+	type RangeSelection,
+} from "lexical";
+import { type FC, useEffect } from "react";
+
+function $containsDecoratorNode(node: LexicalNode | null): boolean {
+	if (!node) return false;
+	if ($isDecoratorNode(node)) return true;
+	if (!$isElementNode(node)) return false;
+	return node.getChildren().some($containsDecoratorNode);
+}
+
+function $backspaceHitsDecoratorNode(selection: RangeSelection): boolean {
+	const { anchor } = selection;
+	if (anchor.type === "element") {
+		const node = anchor.getNode();
+		if (anchor.offset === 0) {
+			const topBlock = node.getTopLevelElement() ?? node;
+			return $containsDecoratorNode(topBlock.getPreviousSibling());
+		}
+		return $containsDecoratorNode(node.getChildAtIndex(anchor.offset - 1));
+	}
+
+	if (anchor.offset !== 0) return false;
+	const textNode = anchor.getNode();
+	if ($containsDecoratorNode(textNode.getPreviousSibling())) return true;
+
+	const topBlock = textNode.getTopLevelElement();
+	if (topBlock?.getFirstDescendant() !== textNode) return false;
+	return $containsDecoratorNode(topBlock.getPreviousSibling());
+}
+
+export function $shouldUseNativeBackspace(
+	selection: BaseSelection | null,
+): boolean {
+	if (!$isRangeSelection(selection)) return false;
+	if (selection.getNodes().some($containsDecoratorNode)) return false;
+	return !selection.isCollapsed() || !$backspaceHitsDecoratorNode(selection);
+}
+
+export function registerIOSBackspaceCommand(
+	editor: LexicalEditor,
+	useNativeBackspace: boolean,
+): () => void {
+	return editor.registerCommand(
+		KEY_BACKSPACE_COMMAND,
+		(event) => {
+			if (!useNativeBackspace) return false;
+
+			const selection = $getSelection();
+			if ($shouldUseNativeBackspace(selection)) return true;
+			if (!$isRangeSelection(selection)) return false;
+
+			// WebKit native deletion can desynchronize contentEditable=false decorator nodes.
+			event.preventDefault();
+			return editor.dispatchCommand(DELETE_CHARACTER_COMMAND, true);
+		},
+		COMMAND_PRIORITY_HIGH,
+	);
+}
+
+const IOSBackspacePlugin: FC = function IOSBackspacePlugin() {
+	const [editor] = useLexicalComposerContext();
+
+	useEffect(() => {
+		// Lexical's default Backspace handler blocks the beforeinput event WebKit needs for delete acceleration.
+		return registerIOSBackspaceCommand(editor, IS_IOS && CAN_USE_BEFORE_INPUT);
+	}, [editor]);
+
+	return null;
+};
+
+export { IOSBackspacePlugin };