final Map<String, Object> doc = new HashMap<>();
        doc.put("title", "Test Title");
        doc.put("url", "https://example.com");
        doc.put("doc_id", "doc-123");
        doc.put("content_description", "Test snippet");

        final ChatSource source = new ChatSource(5, doc);

        assertEquals(5, source.getIndex());
        assertEquals("Test Title", source.getTitle());