1
pip install synapsekit
Installs rank-bm25 automatically as a declared dependency.
2
Done. BM25 works immediately via HybridSearchRetriever.
✓ Zero extra installs. rank-bm25 is bundled.
1
pip install langchain langchain-community
BM25Retriever class is included. Import succeeds.
2
pip install rank-bm25
Not installed automatically. Without it, BM25Retriever.from_texts() raises ModuleNotFoundError at runtime.
⚠ Silent runtime failure. Import succeeds but retriever fails.
1
pip install llama-index-core
BM25Retriever is NOT included. Import fails immediately.
2
pip install llama-index-retrievers-bm25
Dedicated integration package required. Fails at import time — honest failure mode.
ℹ Explicit install required. Fails at import (not runtime).