diff --git a/src/components/Chat/Chat.test.tsx b/src/components/Chat/Chat.test.tsx
index defcead..e4435e8 100644
--- a/src/components/Chat/Chat.test.tsx
+++ b/src/components/Chat/Chat.test.tsx
@@ -242,6 +242,24 @@ describe('ChatLayout', () => {
     expect(layout).toHaveStyle({color: 'rgb(255, 0, 0)'});
     expect(ref).toHaveBeenCalledWith(expect.any(HTMLDivElement));
   });
+
+  it('forwards the curated passthrough props to the root', () => {
+    render(
+      <>
+        <span id="chat-label">Support chat</span>
+        <ChatLayout
+          aria-labelledby="chat-label"
+          composer={null}
+          data-testid="layout"
+          id="chat"
+        />
+      </>,
+    );
+
+    const layout = screen.getByTestId('layout');
+    expect(layout).toHaveAttribute('id', 'chat');
+    expect(layout).toHaveAttribute('aria-labelledby', 'chat-label');
+  });
 });
 
 describe('ChatScrollButton', () => {
diff --git a/src/components/Chat/ChatComposer.test.tsx b/src/components/Chat/ChatComposer.test.tsx
index 87e459c..fbfdbc2 100644
--- a/src/components/Chat/ChatComposer.test.tsx
+++ b/src/components/Chat/ChatComposer.test.tsx
@@ -230,6 +230,24 @@ describe('ChatComposer', () => {
     expect(composer).toHaveStyle({color: 'rgb(255, 0, 0)'});
     expect(ref).toHaveBeenCalledWith(expect.any(HTMLDivElement));
   });
+
+  it('forwards the curated passthrough props to the root', () => {
+    render(
+      <>
+        <span id="composer-label">Message</span>
+        <ChatComposer
+          aria-labelledby="composer-label"
+          data-testid="composer"
+          id="composer"
+          onSubmit={vi.fn()}
+        />
+      </>,
+    );
+
+    const composer = screen.getByTestId('composer');
+    expect(composer).toHaveAttribute('id', 'composer');
+    expect(composer).toHaveAttribute('aria-labelledby', 'composer-label');
+  });
 });
 
 describe('ChatComposerInput', () => {
@@ -266,6 +284,52 @@ describe('ChatComposerInput', () => {
 
     expect(onSubmit).not.toHaveBeenCalled();
   });
+
+  it('forwards the curated textarea props', async () => {
+    const user = userEvent.setup();
+    const onBlur = vi.fn();
+    const onFocus = vi.fn();
+    render(
+      <>
+        <span id="input-hint">Enter sends</span>
+        <ChatComposerInput
+          aria-describedby="input-hint"
+          data-testid="input"
+          enterKeyHint="send"
+          id="composer-input"
+          maxLength={100}
+          name="message"
+          onBlur={onBlur}
+          onFocus={onFocus}
+        />
+        <button type="button">Elsewhere</button>
+      </>,
+    );
+
+    const input = screen.getByTestId('input');
+    expect(input).toHaveAttribute('id', 'composer-input');
+    expect(input).toHaveAttribute('name', 'message');
+    expect(input).toHaveAttribute('aria-describedby', 'input-hint');
+    expect(input).toHaveAttribute('enterkeyhint', 'send');
+    expect(input).toHaveAttribute('maxlength', '100');
+
+    await user.click(input);
+    expect(onFocus).toHaveBeenCalledOnce();
+
+    await user.click(screen.getByRole('button', {name: 'Elsewhere'}));
+    expect(onBlur).toHaveBeenCalledOnce();
+  });
+
+  it('forwards onPaste so consumers can intercept pasted content', async () => {
+    const user = userEvent.setup();
+    const onPaste = vi.fn();
+    render(<ChatComposerInput data-testid="input" onPaste={onPaste} />);
+
+    await user.click(screen.getByTestId('input'));
+    await user.paste('pasted text');
+
+    expect(onPaste).toHaveBeenCalledOnce();
+  });
 });
 
 describe('computeInputHeight', () => {
diff --git a/src/components/Chat/ChatComposer.tsx b/src/components/Chat/ChatComposer.tsx
index d2bc048..6be2efc 100644
--- a/src/components/Chat/ChatComposer.tsx
+++ b/src/components/Chat/ChatComposer.tsx
@@ -1,13 +1,7 @@
 'use client';
 
 import {CircleAlert, TriangleAlert} from 'lucide-react';
-import type {
-  ComponentPropsWithoutRef,
-  CSSProperties,
-  MouseEvent,
-  ReactNode,
-  Ref,
-} from 'react';
+import type {CSSProperties, MouseEvent, ReactNode, Ref} from 'react';
 import {useCallback, useMemo, useRef, useState} from 'react';
 import {chatComposerRecipe} from 'components/Chat/ChatComposer.recipe';
 import {ChatComposerInput} from 'components/Chat/ChatComposerInput';
@@ -16,6 +10,7 @@ import {
   useChatLayoutContext,
   type ChatDensity,
 } from 'components/Chat/ChatContext';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import {ChatSendButton} from 'components/Chat/ChatSendButton';
 import {Icon} from 'components/Icon';
 import isNonEmptyReactNode from 'internal/isNonEmptyReactNode';
@@ -32,10 +27,7 @@ export interface ChatComposerStatus {
   type: 'error' | 'warning';
 }
 
-export interface ChatComposerProps extends Omit<
-  ComponentPropsWithoutRef<'div'>,
-  'children' | 'onChange' | 'onSubmit'
-> {
+export interface ChatComposerProps extends ChatPassthroughProps {
   /**
    * Additional CSS class names applied to the root element.
    */
@@ -153,7 +145,7 @@ export function ChatComposer({
   statusPosition = 'bottom',
   style,
   value: controlledValue,
-  ...rest
+  ...passthrough
 }: ChatComposerProps): React.JSX.Element {
   const layoutContext = useChatLayoutContext();
   const density = densityProp ?? layoutContext?.density ?? 'balanced';
@@ -241,7 +233,7 @@ export function ChatComposer({
   return (
     <ChatComposerContext value={composerContext}>
       <div
-        {...rest}
+        {...passthrough}
         className={cx(classes.root, className)}
         data-testid={dataTestId}
         ref={ref}
diff --git a/src/components/Chat/ChatComposerInput.tsx b/src/components/Chat/ChatComposerInput.tsx
index 206f33a..67d5d66 100644
--- a/src/components/Chat/ChatComposerInput.tsx
+++ b/src/components/Chat/ChatComposerInput.tsx
@@ -2,10 +2,13 @@
 
 import type {
   ChangeEvent,
-  ComponentPropsWithoutRef,
+  ClipboardEventHandler,
   CSSProperties,
+  FocusEventHandler,
   KeyboardEvent,
+  KeyboardEventHandler,
   Ref,
+  TextareaHTMLAttributes,
 } from 'react';
 import {useRef, useState} from 'react';
 import {chatComposerInputRecipe} from 'components/Chat/ChatComposerInput.recipe';
@@ -14,6 +17,7 @@ import {
   DEFAULT_LINE_HEIGHT,
 } from 'components/Chat/ChatComposerInput.utils';
 import {useChatComposerContext} from 'components/Chat/ChatContext';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import {isComposingEvent} from 'internal/isComposingEvent';
 import {mergeRefs} from 'internal/mergeRefs';
 import {useIsomorphicLayoutEffect} from 'internal/useIsomorphicLayoutEffect';
@@ -21,10 +25,11 @@ import {cx} from 'utils/cx';
 
 const rootClass = chatComposerInputRecipe();
 
-export interface ChatComposerInputProps extends Omit<
-  ComponentPropsWithoutRef<'textarea'>,
-  'onChange' | 'value'
-> {
+export interface ChatComposerInputProps extends ChatPassthroughProps {
+  /**
+   * HTML `autocomplete` attribute for the textarea.
+   */
+  autoComplete?: string;
   /**
    * Additional CSS class names applied to the textarea.
    */
@@ -33,12 +38,20 @@ export interface ChatComposerInputProps extends Omit<
    * Test ID applied to the textarea.
    */
   'data-testid'?: string;
+  /**
+   * Action label shown on the virtual keyboard's enter key.
+   */
+  enterKeyHint?: TextareaHTMLAttributes<HTMLTextAreaElement>['enterKeyHint'];
   /**
    * Whether the input is disabled. Defaults to the surrounding ChatComposer
    * state.
    * @default false
    */
   isDisabled?: boolean;
+  /**
+   * Maximum number of characters the user can type.
+   */
+  maxLength?: number;
   /**
    * Maximum number of lines the input grows to before scrolling.
    * @default 8
@@ -49,11 +62,33 @@ export interface ChatComposerInputProps extends Omit<
    * @default 1
    */
   minRows?: number;
+  /**
+   * HTML `name` attribute for form submission.
+   */
+  name?: string;
+  /**
+   * Blur event handler for the textarea.
+   */
+  onBlur?: FocusEventHandler<HTMLTextAreaElement>;
   /**
    * Called when the value changes. Defaults to the surrounding ChatComposer
    * state.
    */
   onChange?: (value: string) => void;
+  /**
+   * Focus event handler for the textarea.
+   */
+  onFocus?: FocusEventHandler<HTMLTextAreaElement>;
+  /**
+   * Keyboard event handler for the textarea, called before the built-in
+   * Enter-to-submit handling. Call `preventDefault()` to suppress it.
+   */
+  onKeyDown?: KeyboardEventHandler<HTMLTextAreaElement>;
+  /**
+   * Paste event handler for the textarea — use to intercept pasted files or
+   * rich content.
+   */
+  onPaste?: ClipboardEventHandler<HTMLTextAreaElement>;
   /**
    * Called with the trimmed value when the user presses Enter. Defaults to
    * submitting the surrounding ChatComposer.
@@ -97,7 +132,7 @@ export function ChatComposerInput({
   ref,
   style,
   value,
-  ...rest
+  ...passthrough
 }: ChatComposerInputProps): React.JSX.Element {
   const composer = useChatComposerContext();
   const [internalValue, setInternalValue] = useState('');
@@ -150,7 +185,7 @@ export function ChatComposerInput({
 
   return (
     <textarea
-      {...rest}
+      {...passthrough}
       className={cx(rootClass, className)}
       data-testid={dataTestId}
       disabled={currentDisabled}
diff --git a/src/components/Chat/ChatLayout.tsx b/src/components/Chat/ChatLayout.tsx
index 3d1a955..02ce8fe 100644
--- a/src/components/Chat/ChatLayout.tsx
+++ b/src/components/Chat/ChatLayout.tsx
@@ -1,15 +1,10 @@
 'use client';
 
-import type {
-  ComponentPropsWithoutRef,
-  CSSProperties,
-  ReactNode,
-  Ref,
-  RefObject,
-} from 'react';
+import type {CSSProperties, ReactNode, Ref, RefObject} from 'react';
 import {useEffect, useMemo, useRef, useState} from 'react';
 import {ChatLayoutContext, type ChatDensity} from 'components/Chat/ChatContext';
 import {chatLayoutRecipe} from 'components/Chat/ChatLayout.recipe';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import {ChatScrollButton} from 'components/Chat/ChatScrollButton';
 import {useChatNewMessages} from 'components/Chat/useChatNewMessages';
 import {useChatStreamScroll} from 'components/Chat/useChatStreamScroll';
@@ -35,7 +30,7 @@ function hasVisibleContent(children: ReactNode): boolean {
   return !(Array.isArray(children) && children.length === 0);
 }
 
-export interface ChatLayoutProps extends ComponentPropsWithoutRef<'div'> {
+export interface ChatLayoutProps extends ChatPassthroughProps {
   /**
    * Message content — typically a ChatMessageList. Flows naturally and
    * scrolls behind the composer dock.
@@ -96,7 +91,7 @@ export function ChatLayout({
   scrollButton,
   scrollRef: externalScrollRef,
   style,
-  ...rest
+  ...passthrough
 }: ChatLayoutProps): React.JSX.Element {
   const rootRef = useRef<HTMLDivElement>(null);
   const dockContainerRef = useRef<HTMLDivElement>(null);
@@ -165,7 +160,7 @@ export function ChatLayout({
   return (
     <ChatLayoutContext value={layoutContext}>
       <div
-        {...rest}
+        {...passthrough}
         className={cx(classes.root, className)}
         data-density={density}
         data-testid={dataTestId}
diff --git a/src/components/Chat/ChatMessage.test.tsx b/src/components/Chat/ChatMessage.test.tsx
index ae451bb..ae3ee7f 100644
--- a/src/components/Chat/ChatMessage.test.tsx
+++ b/src/components/Chat/ChatMessage.test.tsx
@@ -107,6 +107,72 @@ describe('ChatMessage', () => {
     expect(message).toHaveStyle({color: 'rgb(255, 0, 0)'});
     expect(ref).toHaveBeenCalledWith(expect.any(HTMLElement));
   });
+
+  it('forwards the curated passthrough props', () => {
+    render(
+      <>
+        <span id="msg-desc">Sent from the web client</span>
+        <ChatMessage
+          aria-describedby="msg-desc"
+          data-testid="message"
+          id="msg-1"
+          sender="user">
+          Hi
+        </ChatMessage>
+      </>,
+    );
+
+    const message = screen.getByTestId('message');
+    expect(message).toHaveAttribute('id', 'msg-1');
+    expect(message).toHaveAttribute('aria-describedby', 'msg-desc');
+  });
+
+  it('lets a consumer label override the generated one', () => {
+    const {rerender} = render(
+      <ChatMessage data-testid="message" sender="user">
+        Hi
+      </ChatMessage>,
+    );
+
+    expect(screen.getByTestId('message')).toHaveAttribute(
+      'aria-label',
+      'Message from user',
+    );
+
+    rerender(
+      <ChatMessage
+        aria-label="Your greeting"
+        data-testid="message"
+        sender="user">
+        Hi
+      </ChatMessage>,
+    );
+
+    expect(screen.getByTestId('message')).toHaveAttribute(
+      'aria-label',
+      'Your greeting',
+    );
+  });
+
+  it('lets a consumer aria-labelledby override the generated name id', () => {
+    render(
+      <>
+        <span id="sender-label">Ada</span>
+        <ChatMessage
+          aria-labelledby="sender-label"
+          data-testid="message"
+          name="Ada Lovelace"
+          sender="assistant">
+          Hi
+        </ChatMessage>
+      </>,
+    );
+
+    expect(screen.getByTestId('message')).toHaveAttribute(
+      'aria-labelledby',
+      'sender-label',
+    );
+  });
 });
 
 describe('ChatMessageBubble', () => {
@@ -210,6 +276,20 @@ describe('ChatMessageBubble', () => {
     expect(bubble).toHaveStyle({color: 'rgb(255, 0, 0)'});
     expect(ref).toHaveBeenCalledWith(expect.any(HTMLDivElement));
   });
+
+  it('forwards the curated passthrough props', () => {
+    render(
+      <ChatMessage sender="user">
+        <ChatMessageBubble aria-label="Greeting" data-testid="bubble" id="b1">
+          Hi
+        </ChatMessageBubble>
+      </ChatMessage>,
+    );
+
+    const bubble = screen.getByTestId('bubble');
+    expect(bubble).toHaveAttribute('id', 'b1');
+    expect(bubble).toHaveAttribute('aria-label', 'Greeting');
+  });
 });
 
 describe('ChatMessageMetadata', () => {
@@ -261,6 +341,21 @@ describe('ChatMessageMetadata', () => {
       {exact: true},
     );
   });
+
+  it('forwards the curated passthrough props', () => {
+    render(
+      <ChatMessageMetadata
+        aria-label="Message details"
+        data-testid="metadata"
+        id="meta-1"
+        timestamp="1:00"
+      />,
+    );
+
+    const metadata = screen.getByTestId('metadata');
+    expect(metadata).toHaveAttribute('id', 'meta-1');
+    expect(metadata).toHaveAttribute('aria-label', 'Message details');
+  });
 });
 
 describe('ChatSystemMessage', () => {
@@ -325,4 +420,34 @@ describe('ChatSystemMessage', () => {
     expect(message).toHaveStyle({color: 'rgb(255, 0, 0)'});
     expect(ref).toHaveBeenCalledWith(expect.any(HTMLDivElement));
   });
+
+  it('forwards the curated passthrough props in both variants', () => {
+    const {rerender} = render(
+      <ChatSystemMessage aria-label="Notice" data-testid="system" id="sys-1">
+        Conversation started
+      </ChatSystemMessage>,
+    );
+
+    expect(screen.getByTestId('system')).toHaveAttribute('id', 'sys-1');
+    expect(screen.getByTestId('system')).toHaveAttribute(
+      'aria-label',
+      'Notice',
+    );
+
+    rerender(
+      <ChatSystemMessage
+        aria-label="Notice"
+        data-testid="system"
+        id="sys-1"
+        variant="divider">
+        Today
+      </ChatSystemMessage>,
+    );
+
+    expect(screen.getByTestId('system')).toHaveAttribute('id', 'sys-1');
+    expect(screen.getByTestId('system')).toHaveAttribute(
+      'aria-label',
+      'Notice',
+    );
+  });
 });
diff --git a/src/components/Chat/ChatMessage.tsx b/src/components/Chat/ChatMessage.tsx
index b9c1272..5c61cf1 100644
--- a/src/components/Chat/ChatMessage.tsx
+++ b/src/components/Chat/ChatMessage.tsx
@@ -1,11 +1,6 @@
 'use client';
 
-import type {
-  ComponentPropsWithoutRef,
-  CSSProperties,
-  ReactNode,
-  Ref,
-} from 'react';
+import type {CSSProperties, ReactNode, Ref} from 'react';
 import {useId, useMemo} from 'react';
 import {
   ChatMessageContext,
@@ -14,10 +9,11 @@ import {
   type ChatMessageSender,
 } from 'components/Chat/ChatContext';
 import {chatMessageRecipe} from 'components/Chat/ChatMessage.recipe';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import isNonEmptyReactNode from 'internal/isNonEmptyReactNode';
 import {cx} from 'utils/cx';
 
-export interface ChatMessageProps extends ComponentPropsWithoutRef<'article'> {
+export interface ChatMessageProps extends ChatPassthroughProps {
   /**
    * Avatar rendered beside the message. Ignored for `system` messages.
    */
@@ -75,6 +71,8 @@ export interface ChatMessageProps extends ComponentPropsWithoutRef<'article'> {
  * name, and metadata around the message content.
  */
 export function ChatMessage({
+  'aria-label': ariaLabel,
+  'aria-labelledby': ariaLabelledby,
   avatar,
   children,
   className,
@@ -85,7 +83,7 @@ export function ChatMessage({
   ref,
   sender,
   style,
-  ...rest
+  ...passthrough
 }: ChatMessageProps): React.JSX.Element {
   const listContext = useChatListContext();
   const density = densityProp ?? listContext?.density ?? 'balanced';
@@ -99,9 +97,11 @@ export function ChatMessage({
   return (
     <ChatMessageContext value={contextValue}>
       <article
-        {...rest}
-        aria-label={hasName ? undefined : `Message from ${sender}`}
-        aria-labelledby={hasName ? nameId : undefined}
+        {...passthrough}
+        aria-label={
+          ariaLabel ?? (hasName ? undefined : `Message from ${sender}`)
+        }
+        aria-labelledby={ariaLabelledby ?? (hasName ? nameId : undefined)}
         className={cx(classes.root, className)}
         data-chat-message=""
         data-sender={sender}
diff --git a/src/components/Chat/ChatMessageBubble.tsx b/src/components/Chat/ChatMessageBubble.tsx
index bd17dab..3f17105 100644
--- a/src/components/Chat/ChatMessageBubble.tsx
+++ b/src/components/Chat/ChatMessageBubble.tsx
@@ -1,13 +1,9 @@
 'use client';
 
-import type {
-  ComponentPropsWithoutRef,
-  CSSProperties,
-  ReactNode,
-  Ref,
-} from 'react';
+import type {CSSProperties, ReactNode, Ref} from 'react';
 import {useChatMessageContext} from 'components/Chat/ChatContext';
 import {chatMessageBubbleRecipe} from 'components/Chat/ChatMessageBubble.recipe';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import isNonEmptyReactNode from 'internal/isNonEmptyReactNode';
 import {cx} from 'utils/cx';
 
@@ -15,7 +11,7 @@ export type ChatMessageBubbleVariant = 'filled' | 'ghost';
 
 export type ChatMessageBubbleGroup = 'first' | 'last' | 'middle';
 
-export interface ChatMessageBubbleProps extends ComponentPropsWithoutRef<'div'> {
+export interface ChatMessageBubbleProps extends ChatPassthroughProps {
   /**
    * Bubble content — text or any ReactNode.
    */
@@ -74,7 +70,7 @@ export function ChatMessageBubble({
   ref,
   style,
   variant = 'filled',
-  ...rest
+  ...passthrough
 }: ChatMessageBubbleProps): React.JSX.Element {
   const messageContext = useChatMessageContext();
   const sender = messageContext?.sender ?? 'assistant';
@@ -89,7 +85,7 @@ export function ChatMessageBubble({
         </div>
       ) : null}
       <div
-        {...rest}
+        {...passthrough}
         className={cx(classes.bubble, className)}
         data-testid={dataTestId}
         ref={ref}
diff --git a/src/components/Chat/ChatMessageList.test.tsx b/src/components/Chat/ChatMessageList.test.tsx
index 576456f..442ae11 100644
--- a/src/components/Chat/ChatMessageList.test.tsx
+++ b/src/components/Chat/ChatMessageList.test.tsx
@@ -182,4 +182,40 @@ describe('ChatMessageList', () => {
     expect(list).toHaveStyle({color: 'rgb(255, 0, 0)'});
     expect(ref).toHaveBeenCalledWith(expect.any(HTMLDivElement));
   });
+
+  it('forwards the curated passthrough props', () => {
+    render(
+      <>
+        <span id="list-label">Conversation</span>
+        <ChatMessageList
+          aria-labelledby="list-label"
+          data-testid="list"
+          id="log">
+          <ChatMessage sender="user">Hi</ChatMessage>
+        </ChatMessageList>
+      </>,
+    );
+
+    const list = screen.getByTestId('list');
+    expect(list).toHaveAttribute('id', 'log');
+    expect(list).toHaveAttribute('aria-labelledby', 'list-label');
+  });
+
+  it('defaults aria-live to polite and allows turning it off', () => {
+    const {rerender} = render(
+      <ChatMessageList data-testid="list">
+        <ChatMessage sender="user">Hi</ChatMessage>
+      </ChatMessageList>,
+    );
+
+    expect(screen.getByTestId('list')).toHaveAttribute('aria-live', 'polite');
+
+    rerender(
+      <ChatMessageList aria-live="off" data-testid="list">
+        <ChatMessage sender="user">Hi</ChatMessage>
+      </ChatMessageList>,
+    );
+
+    expect(screen.getByTestId('list')).toHaveAttribute('aria-live', 'off');
+  });
 });
diff --git a/src/components/Chat/ChatMessageList.tsx b/src/components/Chat/ChatMessageList.tsx
index 7f5a761..56170cf 100644
--- a/src/components/Chat/ChatMessageList.tsx
+++ b/src/components/Chat/ChatMessageList.tsx
@@ -1,11 +1,6 @@
 'use client';
 
-import type {
-  ComponentPropsWithoutRef,
-  CSSProperties,
-  ReactNode,
-  Ref,
-} from 'react';
+import type {AriaAttributes, CSSProperties, ReactNode, Ref} from 'react';
 import {useEffect, useMemo, useRef, useTransition} from 'react';
 import {
   ChatListContext,
@@ -13,13 +8,20 @@ import {
   type ChatDensity,
 } from 'components/Chat/ChatContext';
 import {chatMessageListRecipe} from 'components/Chat/ChatMessageList.recipe';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import {Spinner} from 'components/Spinner';
 import isNonEmptyReactNode from 'internal/isNonEmptyReactNode';
 import type {SpacingToken} from 'internal/spacingTokens';
 import useLatest from 'internal/useLatest';
 import {cx} from 'utils/cx';
 
-export interface ChatMessageListProps extends ComponentPropsWithoutRef<'div'> {
+export interface ChatMessageListProps extends ChatPassthroughProps {
+  /**
+   * How assistive technologies announce messages appended to the log. Set to
+   * `off` for a static transcript that should not be announced.
+   * @default 'polite'
+   */
+  'aria-live'?: AriaAttributes['aria-live'];
   /**
    * Message elements — typically ChatMessage components, optionally mixed
    * with ChatSystemMessage separators.
@@ -70,6 +72,7 @@ export interface ChatMessageListProps extends ComponentPropsWithoutRef<'div'> {
  * load-older-messages support. Auto-scroll is owned by ChatLayout.
  */
 export function ChatMessageList({
+  'aria-live': ariaLive = 'polite',
   children,
   className,
   'data-testid': dataTestId,
@@ -79,7 +82,7 @@ export function ChatMessageList({
   ref,
   scrollToTopAction,
   style,
-  ...rest
+  ...passthrough
 }: ChatMessageListProps): React.JSX.Element {
   const layoutContext = useChatLayoutContext();
   const density = densityProp ?? layoutContext?.density ?? 'balanced';
@@ -138,8 +141,8 @@ export function ChatMessageList({
   return (
     <ChatListContext value={contextValue}>
       <div
-        {...rest}
-        aria-live="polite"
+        {...passthrough}
+        aria-live={ariaLive}
         className={cx(classes.root, className)}
         data-testid={dataTestId}
         ref={ref}
diff --git a/src/components/Chat/ChatMessageMetadata.tsx b/src/components/Chat/ChatMessageMetadata.tsx
index 2bd84c2..662e863 100644
--- a/src/components/Chat/ChatMessageMetadata.tsx
+++ b/src/components/Chat/ChatMessageMetadata.tsx
@@ -1,14 +1,10 @@
 'use client';
 
 import {Check, CheckCheck, CircleAlert, Clock} from 'lucide-react';
-import type {
-  ComponentPropsWithoutRef,
-  CSSProperties,
-  ReactNode,
-  Ref,
-} from 'react';
+import type {CSSProperties, ReactNode, Ref} from 'react';
 import {useChatMessageContext} from 'components/Chat/ChatContext';
 import {chatMessageMetadataRecipe} from 'components/Chat/ChatMessageMetadata.recipe';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import {Icon, type IconComponent} from 'components/Icon';
 import isNonEmptyReactNode from 'internal/isNonEmptyReactNode';
 import {cx} from 'utils/cx';
@@ -27,7 +23,7 @@ const STATUS_CONFIG: Record<
   sent: {icon: Check, label: 'Sent'},
 };
 
-export interface ChatMessageMetadataProps extends ComponentPropsWithoutRef<'div'> {
+export interface ChatMessageMetadataProps extends ChatPassthroughProps {
   /**
    * Additional CSS class names applied to the root element.
    */
@@ -70,7 +66,7 @@ export function ChatMessageMetadata({
   status,
   style,
   timestamp,
-  ...rest
+  ...passthrough
 }: ChatMessageMetadataProps): React.JSX.Element | null {
   const messageContext = useChatMessageContext();
   const sender = messageContext?.sender ?? 'assistant';
@@ -88,7 +84,7 @@ export function ChatMessageMetadata({
 
   return (
     <div
-      {...rest}
+      {...passthrough}
       className={cx(classes.root, className)}
       data-testid={dataTestId}
       ref={ref}
diff --git a/src/components/Chat/ChatPassthroughProps.ts b/src/components/Chat/ChatPassthroughProps.ts
new file mode 100644
index 0000000..571ff05
--- /dev/null
+++ b/src/components/Chat/ChatPassthroughProps.ts
@@ -0,0 +1,24 @@
+import type {AriaAttributes} from 'react';
+
+/**
+ * The identity and description props every Chat container forwards to its root
+ * element.
+ */
+export interface ChatPassthroughProps {
+  /**
+   * Identifies the element(s) that describe the region.
+   */
+  'aria-describedby'?: AriaAttributes['aria-describedby'];
+  /**
+   * Accessible label for the region.
+   */
+  'aria-label'?: AriaAttributes['aria-label'];
+  /**
+   * Identifies the element(s) that label the region.
+   */
+  'aria-labelledby'?: AriaAttributes['aria-labelledby'];
+  /**
+   * HTML `id` attribute applied to the root element.
+   */
+  id?: string;
+}
diff --git a/src/components/Chat/ChatSystemMessage.tsx b/src/components/Chat/ChatSystemMessage.tsx
index 8fe349b..3d16482 100644
--- a/src/components/Chat/ChatSystemMessage.tsx
+++ b/src/components/Chat/ChatSystemMessage.tsx
@@ -1,9 +1,5 @@
-import type {
-  ComponentPropsWithoutRef,
-  CSSProperties,
-  ReactNode,
-  Ref,
-} from 'react';
+import type {CSSProperties, ReactNode, Ref} from 'react';
+import type {ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 import {chatSystemMessageRecipe} from 'components/Chat/ChatSystemMessage.recipe';
 import {Divider} from 'components/Divider';
 import isNonEmptyReactNode from 'internal/isNonEmptyReactNode';
@@ -11,7 +7,7 @@ import {cx} from 'utils/cx';
 
 export type ChatSystemMessageVariant = 'default' | 'divider';
 
-export interface ChatSystemMessageProps extends ComponentPropsWithoutRef<'div'> {
+export interface ChatSystemMessageProps extends ChatPassthroughProps {
   /**
    * System message content — text or any ReactNode.
    */
@@ -56,14 +52,14 @@ export function ChatSystemMessage({
   ref,
   style,
   variant = 'default',
-  ...rest
+  ...passthrough
 }: ChatSystemMessageProps): React.JSX.Element {
   const classes = chatSystemMessageRecipe({variant});
 
   if (variant === 'divider') {
     return (
       <div
-        {...rest}
+        {...passthrough}
         className={cx(classes.dividerWrap, className)}
         data-chat-message=""
         data-sender="system"
@@ -78,7 +74,7 @@ export function ChatSystemMessage({
 
   return (
     <div
-      {...rest}
+      {...passthrough}
       className={cx(classes.root, className)}
       data-chat-message=""
       data-sender="system"
diff --git a/src/components/Chat/index.ts b/src/components/Chat/index.ts
index d6113eb..2278c81 100644
--- a/src/components/Chat/index.ts
+++ b/src/components/Chat/index.ts
@@ -32,6 +32,7 @@ export {
   type ChatMessageMetadataProps,
   type ChatMessageStatus,
 } from 'components/Chat/ChatMessageMetadata';
+export {type ChatPassthroughProps} from 'components/Chat/ChatPassthroughProps';
 export {
   ChatScrollButton,
   type ChatScrollButtonProps,
diff --git a/src/index.ts b/src/index.ts
index 90cd112..249e964 100644
--- a/src/index.ts
+++ b/src/index.ts
@@ -35,6 +35,7 @@ export {
   type ChatMessageProps,
   type ChatMessageSender,
   type ChatMessageStatus,
+  type ChatPassthroughProps,
   type ChatScrollButtonProps,
   type ChatSendButtonProps,
   type ChatSystemMessageProps,