case "source_titles":
            return buildSourceTitlesContent(msg, summaryMaxChars);
        case "source_titles_and_urls":
            return buildSourceTitlesAndUrlsContent(msg);
        case "truncated":
            return buildTruncatedContent(msg, assistantMaxChars);
        case "none":
            return null;
        default:
            return msg.getContent();