{
  "format": "bm25_inverted_index_v1",
  "built_from": "exports/chunks.ndjson",
  "corpus_version_hint": "2026-02-23",
  "doc_count": 276,
  "avgdl": 25.94927536231884,
  "bm25": {
    "k1": 1.2,
    "b": 0.75,
    "idf": "log(1 + (N - df + 0.5)/(df + 0.5))"
  },
  "tokenizer": {
    "type": "regex",
    "pattern": "[a-z0-9]+",
    "lowercase": true
  },
  "sharding": {
    "num_shards": 16,
    "function": "sha1(term)[:8] mod num_shards",
    "file_pattern": "postings_shard_{:02d}.json"
  },
  "notes": "Tiny-agent friendly: fetch only shard files for query terms."
}