return ROLE_USER.equals(role);
    }

    /**
     * Checks if this is an assistant message.
     *
     * @return true if this is an assistant message
     */
    public boolean isAssistant() {
        return ROLE_ASSISTANT.equals(role);
    }

    /**
     * Gets the HTML-rendered content.
     *
     * @return the HTML content, or null if not rendered
     */

        final ChatMessage unknownMessage = new ChatMessage("unknown", "test");

        assertFalse(userMessage.isAssistant());
        assertTrue(assistantMessage.isAssistant());
        assertFalse(unknownMessage.isAssistant());
    }

    @Test
    public void test_roleConstants() {
        assertEquals("user", ChatMessage.ROLE_USER);

            for (final ChatMessage msg : session.getMessages()) {
                if (msg.isUser()) {
                    history.add(LlmMessage.user(msg.getContent()));
                } else if (msg.isAssistant()) {
                    final String content =
                            buildAssistantHistoryContent(msg, assistantContentMode, testAssistantMaxChars, testSummaryMaxChars);
                    if (content != null) {

        for (final ChatMessage msg : session.getMessages()) {
            if (msg.isUser()) {
                history.add(LlmMessage.user(msg.getContent()));
            } else if (msg.isAssistant()) {
                final String content = buildAssistantHistoryContent(msg, assistantContentMode, assistantMaxChars, summaryMaxChars);
                if (content != null) {