{
  "id": "hard_retrieval_v1",
  "description": "Harder retrieval experiments over multi-hop, distractor-heavy Chinese benchmark data.",
  "metrics": {
    "k_values": [1, 3, 5]
  },
  "experiments": [
    {
      "name": "chunk_vector_hard",
      "description": "Flat chunk index with vector retrieval.",
      "parser_mode": "preparsed",
      "creation_settings": {
        "index_type": "chunk",
        "chunk_size": 220,
        "overlap": 30
      },
      "retrieval_settings": {
        "search_type": "vector",
        "top_k": 5,
        "query_rewrite": "off"
      }
    },
    {
      "name": "chunk_full_text_hard",
      "description": "Flat chunk index with full-text retrieval.",
      "parser_mode": "preparsed",
      "creation_settings": {
        "index_type": "chunk",
        "chunk_size": 220,
        "overlap": 30
      },
      "retrieval_settings": {
        "search_type": "full_text",
        "top_k": 5,
        "query_rewrite": "off"
      }
    },
    {
      "name": "chunk_hybrid_hard",
      "description": "Flat chunk index with hybrid retrieval.",
      "parser_mode": "preparsed",
      "creation_settings": {
        "index_type": "chunk",
        "chunk_size": 220,
        "overlap": 30
      },
      "retrieval_settings": {
        "search_type": "hybrid",
        "vector_weight": 0.65,
        "top_k": 5,
        "query_rewrite": "off"
      }
    },
    {
      "name": "parent_child_hybrid_hard",
      "description": "Parent-child index with hybrid retrieval.",
      "parser_mode": "preparsed",
      "creation_settings": {
        "index_type": "parent_child",
        "parent_chunk_size": 320,
        "child_chunk_size": 110,
        "overlap": 25
      },
      "retrieval_settings": {
        "search_type": "hybrid",
        "vector_weight": 0.65,
        "top_k": 5,
        "query_rewrite": "off"
      }
    },
    {
      "name": "chunk_multi_query_hard",
      "description": "Flat chunk index with deterministic multi-query rewrite and hybrid retrieval.",
      "parser_mode": "preparsed",
      "creation_settings": {
        "index_type": "chunk",
        "chunk_size": 220,
        "overlap": 30
      },
      "retrieval_settings": {
        "search_type": "hybrid",
        "vector_weight": 0.65,
        "top_k": 5,
        "query_rewrite": "multi_query",
        "rewrite_llm_model_uuid": "local-fake-llm"
      }
    }
  ]
}