Description

This fixes graph nodes not being created at all for an empty graph.

Done some debugging and found that in graph_memory.py:102 the LLM chooses the NOOP tool despite a clear indication that a memory should be added:

Further digging and #1879 (comment) showed that the LLM doesn't understand correctly [] as a lack of existing nodes.

The change replaces [] with the word "None" which seems to work.

Fixes #1906

Type of change

Please delete options that are not relevant.

• Bug fix (non-breaking change which fixes an issue)

How Has This Been Tested?

Used the sample graph code from the docs (https://docs.mem0.ai/open-source/graph_memory/overview) with an empty Neo4J DB at Aura:

import os
from dotenv import load_dotenv
load_dotenv()
from mem0 import Memory

config = {
    "graph_store": {
        "provider": "neo4j",
        "config": {
            "url": os.environ["NEO4J_URL"],
            "username": os.environ["NEO4J_USERNAME"],
            "password": os.environ["NEO4J_PASSWORD"]
        }
    },
    "version": "v1.1"
}

m = Memory.from_config(config)
m.add("I like pizza", user_id="alice2")
results = m.search("What food do I like?", user_id="alice2")
print(results)

• Test Script (please provide)

Checklist:

• My code follows the style guidelines of this project
• I have performed a self-review of my own code
• I have commented my code, particularly in hard-to-understand areas
• I have made corresponding changes to the documentation
• My changes generate no new warnings
• I have added tests that prove my fix is effective or that my feature works
• New and Existing unit tests pass locally with my changes
• Any dependent changes have been merged and published in downstream modules
• I have checked my code and corrected any misspellings

Maintainer Checklist

• closes #xxxx (Replace xxxx with the GitHub issue number)
• Made sure Checks passed