Chroma MCP Server

Instructions

Args:
    collection_name: Name of the collection to delete documents from
    ids: List of document IDs to delete

Returns:
    A confirmation message indicating the number of documents deleted.

Raises:
    ValueError: If 'ids' is empty
    Exception: If the collection does not exist or if the delete operation fails.

Implementation Reference

• src/chroma_mcp/server.py:567-606 (handler)

  The main handler function for the 'chroma_delete_documents' tool. It deletes specified documents by IDs from a Chroma collection using the ChromaDB client. Decorated with @mcp.tool() which also serves as the registration in FastMCP.

  @mcp.tool()
  async def chroma_delete_documents(
      collection_name: str,
      ids: List[str]
  ) -> str:
      """Delete documents from a Chroma collection.
  
      Args:
          collection_name: Name of the collection to delete documents from
          ids: List of document IDs to delete
  
      Returns:
          A confirmation message indicating the number of documents deleted.
  
      Raises:
          ValueError: If 'ids' is empty
          Exception: If the collection does not exist or if the delete operation fails.
      """
      if not ids:
          raise ValueError("The 'ids' list cannot be empty.")
  
      client = get_chroma_client()
      try:
          collection = client.get_collection(collection_name)
      except Exception as e:
          raise Exception(
              f"Failed to get collection '{collection_name}': {str(e)}"
          ) from e
  
      try:
          collection.delete(ids=ids)
          return (
              f"Successfully deleted {len(ids)} documents from "
              f"collection '{collection_name}'. Note: Non-existent IDs are ignored by ChromaDB."
          )
      except Exception as e:
          raise Exception(
              f"Failed to delete documents from collection '{collection_name}': {str(e)}"
          ) from e