ChromaDB (Vector Storage)

Notes and gotchas when using ChromaDB as the vector store:

Metadata types

• ChromaDB accepts only simple types in metadata: str, int, float, bool.
• The code filters out None values before saving to Chroma. If you need null, store a sentinel string like "<null>".

Windows file locks

• On Windows, SQLite-based backends can keep file handles open. To avoid "PermissionError" during cleanup:
• Call client.close() to stop background services and close the vector client before deleting files.
• If you see PermissionError, add a short time.sleep(2) and gc.collect() before retrying.

Performance tuning

• Set operation_mode=online to use managed embeddings for faster startup.
• Tune n_results and search_tier to control how many vectors are retrieved.

Backup and restore

• Chroma stores its DB files in the storage_path/chroma directory. Back up this folder to preserve vectors.

» See also: docs/storage/networkx.md