assertTrue(result.length() > 0);
    }

    // ========== additional source_titles tests ==========

    @Test
    public void test_sourceTitles_truncatesLongContent() {
        final ChatMessage msg = createAssistantWithSources("A".repeat(1000), "My Doc");
        final String result = chatClient.testBuildAssistantHistoryContent(msg, "source_titles", 500, 500);
        assertTrue(result.contains("... [truncated]"));

    }

    /**
     * Builds the assistant message content for history based on the specified mode.
     *
     * @param msg the assistant chat message
     * @param mode the content mode (full, smart_summary, source_titles, source_titles_and_urls, truncated, none)
     * @param assistantMaxChars the maximum characters for truncated mode
     * @param summaryMaxChars the maximum characters for summary modes

    }

    // ========== History content mode pattern tests ==========
    // These test the different history shapes that extractHistory() produces
    // depending on rag.chat.history.assistant.content mode (full, source_titles,
    // source_titles_and_urls, truncated, none).

    @Test
    public void test_buildIntentRequest_noneMode_userOnlyHistory() {
        // When mode=none, extractHistory skips assistant messages,

rag.chat.message.max.length=4000
# Highlight settings for RAG search.
rag.chat.highlight.fragment.size=500
rag.chat.highlight.number.of.fragments=3
# History content mode for assistant messages (full, smart_summary, source_titles, source_titles_and_urls, truncated, none).
rag.chat.history.assistant.content=smart_summary

# Index Export
index.export.path=/var/lib/fess/export
index.export.exclude.fields=cache

    /**
     * Get the value for the key 'rag.chat.history.assistant.content'. <br>
     * The value is, e.g. smart_summary <br>
     * comment: History content mode for assistant messages (full, smart_summary, source_titles, source_titles_and_urls, truncated, none).
     * @return The value of found property. (NotNull: if not found, exception but basically no way)
     */
    String getRagChatHistoryAssistantContent();

    /**