diff --git a/packages/client/src/scripts/aiscript/ui.ts b/packages/client/src/scripts/aiscript/ui.ts
new file mode 100644
index 0000000000..c26ae5a4df
--- /dev/null
+++ b/packages/client/src/scripts/aiscript/ui.ts
@@ -0,0 +1,568 @@
+import { utils, values } from '@syuilo/aiscript';
+import { v4 as uuid } from 'uuid';
+import { ref, Ref } from 'vue';
+
+export type AsUiComponentBase = {
+	id: string;
+	hidden?: boolean;
+};
+
+export type AsUiRoot = AsUiComponentBase & {
+	type: 'root';
+	children: AsUiComponent['id'][];
+};
+
+export type AsUiContainer = AsUiComponentBase & {
+	type: 'container';
+	children?: AsUiComponent['id'][];
+	align?: 'left' | 'center' | 'right';
+	bgColor?: string;
+	fgColor?: string;
+	font?: 'serif' | 'sans-serif' | 'monospace';
+	borderWidth?: number;
+	borderColor?: string;
+	padding?: number;
+	rounded?: boolean;
+	hidden?: boolean;
+};
+
+export type AsUiText = AsUiComponentBase & {
+	type: 'text';
+	text?: string;
+	size?: number;
+	bold?: boolean;
+	color?: string;
+	font?: 'serif' | 'sans-serif' | 'monospace';
+};
+
+export type AsUiMfm = AsUiComponentBase & {
+	type: 'mfm';
+	text?: string;
+	size?: number;
+	bold?: boolean;
+	color?: string;
+	font?: 'serif' | 'sans-serif' | 'monospace';
+};
+
+export type AsUiButton = AsUiComponentBase & {
+	type: 'button';
+	text?: string;
+	onClick?: () => void;
+	primary?: boolean;
+	rounded?: boolean;
+	disabled?: boolean;
+};
+
+export type AsUiButtons = AsUiComponentBase & {
+	type: 'buttons';
+	buttons?: AsUiButton[];
+};
+
+export type AsUiSwitch = AsUiComponentBase & {
+	type: 'switch';
+	onChange?: (v: boolean) => void;
+	default?: boolean;
+	label?: string;
+	caption?: string;
+};
+
+export type AsUiTextarea = AsUiComponentBase & {
+	type: 'textarea';
+	onInput?: (v: string) => void;
+	default?: string;
+	label?: string;
+	caption?: string;
+};
+
+export type AsUiTextInput = AsUiComponentBase & {
+	type: 'textInput';
+	onInput?: (v: string) => void;
+	default?: string;
+	label?: string;
+	caption?: string;
+};
+
+export type AsUiNumberInput = AsUiComponentBase & {
+	type: 'numberInput';
+	onInput?: (v: number) => void;
+	default?: number;
+	label?: string;
+	caption?: string;
+};
+
+export type AsUiSelect = AsUiComponentBase & {
+	type: 'select';
+	items?: {
+		text: string;
+		value: string;
+	}[];
+	onChange?: (v: string) => void;
+	default?: string;
+	label?: string;
+	caption?: string;
+};
+
+export type AsUiFolder = AsUiComponentBase & {
+	type: 'folder';
+	children?: AsUiComponent['id'][];
+	title?: string;
+	opened?: boolean;
+};
+
+export type AsUiPostFormButton = AsUiComponentBase & {
+	type: 'postFormButton';
+	text?: string;
+	primary?: boolean;
+	rounded?: boolean;
+	form?: {
+		text: string;
+	};
+};
+
+export type AsUiComponent = AsUiRoot | AsUiContainer | AsUiText | AsUiMfm | AsUiButton | AsUiButtons | AsUiSwitch | AsUiTextarea | AsUiTextInput | AsUiNumberInput | AsUiSelect | AsUiFolder | AsUiPostFormButton;
+
+export function patch(id: string, def: values.Value, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>) {
+	// TODO
+}
+
+function getRootOptions(def: values.Value | undefined): Omit<AsUiRoot, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const children = def.value.get('children');
+	utils.assertArray(children);
+
+	return {
+		children: children.value.map(v => {
+			utils.assertObject(v);
+			return v.value.get('id').value;
+		}),
+	};
+}
+
+function getContainerOptions(def: values.Value | undefined): Omit<AsUiContainer, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const children = def.value.get('children');
+	if (children) utils.assertArray(children);
+	const align = def.value.get('align');
+	if (align) utils.assertString(align);
+	const bgColor = def.value.get('bgColor');
+	if (bgColor) utils.assertString(bgColor);
+	const fgColor = def.value.get('fgColor');
+	if (fgColor) utils.assertString(fgColor);
+	const font = def.value.get('font');
+	if (font) utils.assertString(font);
+	const borderWidth = def.value.get('borderWidth');
+	if (borderWidth) utils.assertNumber(borderWidth);
+	const borderColor = def.value.get('borderColor');
+	if (borderColor) utils.assertString(borderColor);
+	const padding = def.value.get('padding');
+	if (padding) utils.assertNumber(padding);
+	const rounded = def.value.get('rounded');
+	if (rounded) utils.assertBoolean(rounded);
+	const hidden = def.value.get('hidden');
+	if (hidden) utils.assertBoolean(hidden);
+
+	return {
+		children: children ? children.value.map(v => {
+			utils.assertObject(v);
+			return v.value.get('id').value;
+		}) : [],
+		align: align?.value,
+		fgColor: fgColor?.value,
+		bgColor: bgColor?.value,
+		font: font?.value,
+		borderWidth: borderWidth?.value,
+		borderColor: borderColor?.value,
+		padding: padding?.value,
+		rounded: rounded?.value,
+		hidden: hidden?.value,
+	};
+}
+
+function getTextOptions(def: values.Value | undefined): Omit<AsUiText, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const text = def.value.get('text');
+	if (text) utils.assertString(text);
+	const size = def.value.get('size');
+	if (size) utils.assertNumber(size);
+	const bold = def.value.get('bold');
+	if (bold) utils.assertBoolean(bold);
+	const color = def.value.get('color');
+	if (color) utils.assertString(color);
+	const font = def.value.get('font');
+	if (font) utils.assertString(font);
+
+	return {
+		text: text?.value,
+		size: size?.value,
+		bold: bold?.value,
+		color: color?.value,
+		font: font?.value,
+	};
+}
+
+function getMfmOptions(def: values.Value | undefined): Omit<AsUiMfm, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const text = def.value.get('text');
+	if (text) utils.assertString(text);
+	const size = def.value.get('size');
+	if (size) utils.assertNumber(size);
+	const bold = def.value.get('bold');
+	if (bold) utils.assertBoolean(bold);
+	const color = def.value.get('color');
+	if (color) utils.assertString(color);
+	const font = def.value.get('font');
+	if (font) utils.assertString(font);
+
+	return {
+		text: text?.value,
+		size: size?.value,
+		bold: bold?.value,
+		color: color?.value,
+		font: font?.value,
+	};
+}
+
+function getTextInputOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiTextInput, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const onInput = def.value.get('onInput');
+	if (onInput) utils.assertFunction(onInput);
+	const defaultValue = def.value.get('default');
+	if (defaultValue) utils.assertString(defaultValue);
+	const label = def.value.get('label');
+	if (label) utils.assertString(label);
+	const caption = def.value.get('caption');
+	if (caption) utils.assertString(caption);
+
+	return {
+		onInput: (v) => {
+			if (onInput) call(onInput, [utils.jsToVal(v)]);
+		},
+		default: defaultValue?.value,
+		label: label?.value,
+		caption: caption?.value,
+	};
+}
+
+function getTextareaOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiTextarea, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const onInput = def.value.get('onInput');
+	if (onInput) utils.assertFunction(onInput);
+	const defaultValue = def.value.get('default');
+	if (defaultValue) utils.assertString(defaultValue);
+	const label = def.value.get('label');
+	if (label) utils.assertString(label);
+	const caption = def.value.get('caption');
+	if (caption) utils.assertString(caption);
+
+	return {
+		onInput: (v) => {
+			if (onInput) call(onInput, [utils.jsToVal(v)]);
+		},
+		default: defaultValue?.value,
+		label: label?.value,
+		caption: caption?.value,
+	};
+}
+
+function getNumberInputOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiNumberInput, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const onInput = def.value.get('onInput');
+	if (onInput) utils.assertFunction(onInput);
+	const defaultValue = def.value.get('default');
+	if (defaultValue) utils.assertNumber(defaultValue);
+	const label = def.value.get('label');
+	if (label) utils.assertString(label);
+	const caption = def.value.get('caption');
+	if (caption) utils.assertString(caption);
+
+	return {
+		onInput: (v) => {
+			if (onInput) call(onInput, [utils.jsToVal(v)]);
+		},
+		default: defaultValue?.value,
+		label: label?.value,
+		caption: caption?.value,
+	};
+}
+
+function getButtonOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiButton, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const text = def.value.get('text');
+	if (text) utils.assertString(text);
+	const onClick = def.value.get('onClick');
+	if (onClick) utils.assertFunction(onClick);
+	const primary = def.value.get('primary');
+	if (primary) utils.assertBoolean(primary);
+	const rounded = def.value.get('rounded');
+	if (rounded) utils.assertBoolean(rounded);
+	const disabled = def.value.get('disabled');
+	if (disabled) utils.assertBoolean(disabled);
+
+	return {
+		text: text?.value,
+		onClick: () => {
+			if (onClick) call(onClick, []);
+		},
+		primary: primary?.value,
+		rounded: rounded?.value,
+		disabled: disabled?.value,
+	};
+}
+
+function getButtonsOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiButtons, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const buttons = def.value.get('buttons');
+	if (buttons) utils.assertArray(buttons);
+
+	return {
+		buttons: buttons ? buttons.value.map(button => {
+			utils.assertObject(button);
+			const text = button.value.get('text');
+			utils.assertString(text);
+			const onClick = button.value.get('onClick');
+			utils.assertFunction(onClick);
+			const primary = button.value.get('primary');
+			if (primary) utils.assertBoolean(primary);
+			const rounded = button.value.get('rounded');
+			if (rounded) utils.assertBoolean(rounded);
+			const disabled = button.value.get('disabled');
+			if (disabled) utils.assertBoolean(disabled);
+
+			return {
+				text: text.value,
+				onClick: () => {
+					call(onClick, []);
+				},
+				primary: primary?.value,
+				rounded: rounded?.value,
+				disabled: disabled?.value,
+			};
+		}) : [],
+	};
+}
+
+function getSwitchOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiSwitch, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const onChange = def.value.get('onChange');
+	if (onChange) utils.assertFunction(onChange);
+	const defaultValue = def.value.get('default');
+	if (defaultValue) utils.assertBoolean(defaultValue);
+	const label = def.value.get('label');
+	if (label) utils.assertString(label);
+	const caption = def.value.get('caption');
+	if (caption) utils.assertString(caption);
+
+	return {
+		onChange: (v) => {
+			if (onChange) call(onChange, [utils.jsToVal(v)]);
+		},
+		default: defaultValue?.value,
+		label: label?.value,
+		caption: caption?.value,
+	};
+}
+
+function getSelectOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiSelect, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const items = def.value.get('items');
+	if (items) utils.assertArray(items);
+	const onChange = def.value.get('onChange');
+	if (onChange) utils.assertFunction(onChange);
+	const defaultValue = def.value.get('default');
+	if (defaultValue) utils.assertString(defaultValue);
+	const label = def.value.get('label');
+	if (label) utils.assertString(label);
+	const caption = def.value.get('caption');
+	if (caption) utils.assertString(caption);
+
+	return {
+		items: items ? items.value.map(item => {
+			utils.assertObject(item);
+			const text = item.value.get('text');
+			utils.assertString(text);
+			const value = item.value.get('value');
+			if (value) utils.assertString(value);
+			return {
+				text: text.value,
+				value: value ? value.value : text.value,
+			};
+		}) : [],
+		onChange: (v) => {
+			if (onChange) call(onChange, [utils.jsToVal(v)]);
+		},
+		default: defaultValue?.value,
+		label: label?.value,
+		caption: caption?.value,
+	};
+}
+
+function getFolderOptions(def: values.Value | undefined): Omit<AsUiFolder, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const children = def.value.get('children');
+	if (children) utils.assertArray(children);
+	const title = def.value.get('title');
+	if (title) utils.assertString(title);
+	const opened = def.value.get('opened');
+	if (opened) utils.assertBoolean(opened);
+
+	return {
+		children: children ? children.value.map(v => {
+			utils.assertObject(v);
+			return v.value.get('id').value;
+		}) : [],
+		title: title?.value ?? '',
+		opened: opened?.value ?? true,
+	};
+}
+
+function getPostFormButtonOptions(def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>): Omit<AsUiPostFormButton, 'id' | 'type'> {
+	utils.assertObject(def);
+
+	const text = def.value.get('text');
+	if (text) utils.assertString(text);
+	const primary = def.value.get('primary');
+	if (primary) utils.assertBoolean(primary);
+	const rounded = def.value.get('rounded');
+	if (rounded) utils.assertBoolean(rounded);
+	const form = def.value.get('form');
+	if (form) utils.assertObject(form);
+
+	const getForm = () => {
+		const text = form!.value.get('text');
+		utils.assertString(text);
+		return {
+			text: text.value,
+		};
+	};
+
+	return {
+		text: text?.value,
+		primary: primary?.value,
+		rounded: rounded?.value,
+		form: form ? getForm() : {
+			text: '',
+		},
+	};
+}
+
+export function registerAsUiLib(components: Ref<AsUiComponent>[], done: (root: Ref<AsUiRoot>) => void) {
+	const instances = {};
+
+	function createComponentInstance(type: AsUiComponent['type'], def: values.Value | undefined, id: values.Value | undefined, getOptions: (def: values.Value | undefined, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>) => any, call: (fn: values.VFn, args: values.Value[]) => Promise<values.Value>) {
+		if (id) utils.assertString(id);
+		const _id = id?.value ?? uuid();
+		const component = ref({
+			...getOptions(def, call),
+			type,
+			id: _id,
+		});
+		components.push(component);
+		const instance = values.OBJ(new Map([
+			['id', values.STR(_id)],
+			['update', values.FN_NATIVE(([def], opts) => {
+				utils.assertObject(def);
+				const updates = getOptions(def, call);
+				for (const update of def.value.keys()) {
+					if (!Object.hasOwn(updates, update)) continue;
+					component.value[update] = updates[update];
+				}
+			})],
+		]));
+		instances[_id] = instance;
+		return instance;
+	}
+
+	const rootInstance = createComponentInstance('root', utils.jsToVal({ children: [] }), utils.jsToVal('___root___'), getRootOptions, () => {});
+	const rootComponent = components[0] as Ref<AsUiRoot>;
+	done(rootComponent);
+
+	return {
+		'Ui:root': rootInstance,
+
+		'Ui:patch': values.FN_NATIVE(([id, val], opts) => {
+			utils.assertString(id);
+			utils.assertArray(val);
+			patch(id.value, val.value, opts.call);
+		}),
+
+		'Ui:get': values.FN_NATIVE(([id], opts) => {
+			utils.assertString(id);
+			const instance = instances[id.value];
+			if (instance) {
+				return instance;
+			} else {
+				return values.NULL;
+			}
+		}),
+
+		// Ui:root.update({ children: [...] }) の糖衣構文
+		'Ui:render': values.FN_NATIVE(([children], opts) => {
+			utils.assertArray(children);
+
+			rootComponent.value.children = children.value.map(v => {
+				utils.assertObject(v);
+				return v.value.get('id').value;
+			});
+		}),
+
+		'Ui:C:container': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('container', def, id, getContainerOptions, opts.call);
+		}),
+
+		'Ui:C:text': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('text', def, id, getTextOptions, opts.call);
+		}),
+
+		'Ui:C:mfm': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('mfm', def, id, getMfmOptions, opts.call);
+		}),
+
+		'Ui:C:textarea': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('textarea', def, id, getTextareaOptions, opts.call);
+		}),
+
+		'Ui:C:textInput': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('textInput', def, id, getTextInputOptions, opts.call);
+		}),
+
+		'Ui:C:numberInput': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('numberInput', def, id, getNumberInputOptions, opts.call);
+		}),
+
+		'Ui:C:button': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('button', def, id, getButtonOptions, opts.call);
+		}),
+
+		'Ui:C:buttons': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('buttons', def, id, getButtonsOptions, opts.call);
+		}),
+
+		'Ui:C:switch': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('switch', def, id, getSwitchOptions, opts.call);
+		}),
+
+		'Ui:C:select': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('select', def, id, getSelectOptions, opts.call);
+		}),
+
+		'Ui:C:folder': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('folder', def, id, getFolderOptions, opts.call);
+		}),
+
+		'Ui:C:postFormButton': values.FN_NATIVE(([def, id], opts) => {
+			return createComponentInstance('postFormButton', def, id, getPostFormButtonOptions, opts.call);
+		}),
+	};
+}