user_id, agent_id and run_id

Every memory so far has belonged to Ravi. A real system has thousands of customers, several assistants and a conversation that ends. Mem0 has one identifier for each of those.

Identifier	Ties the memory to	Use it for
user_id	a person or account	preferences, facts about them
agent_id	one assistant or persona	what this assistant learned to do
run_id	one session or task	facts that expire with the conversation

At least one is required. More than one narrows the memory further, so it is found only when all of them match.

Example

from pretend_mem0 import memory

shop = memory()
shop.add("Deliver to my office.", user_id="ravi")
shop.add("The customer sounded annoyed.", user_id="ravi", run_id="chat-42")

print(len(shop.get_all(filters={"user_id": "ravi"})["results"]), "for ravi")
print(len(shop.get_all(filters={"run_id": "chat-42"})["results"]), "for this chat")

Both memories belong to Ravi, and only one belongs to this conversation. Filter by the user and you get everything; filter by the run and you get what was true just now.

Why run_id earns its place

Some things are worth remembering for ten minutes and not for a year. That the customer is in a hurry, that they are asking about the order they mentioned two messages ago, that they already tried restarting it. Store those under a run_id and they stay out of next month's search results without anyone having to clean up.

Narrowing with two

Example

from pretend_mem0 import memory

shop = memory()
shop.add("Deliver to my office.", user_id="ravi")
shop.add("The customer sounded annoyed.", user_id="ravi", run_id="chat-42")

both = shop.get_all(filters={"user_id": "ravi", "run_id": "chat-42"})
for stored in both["results"]:
    print(stored["memory"])

Only the memory carrying both identifiers comes back. This is how one assistant serving many people in many sessions keeps them apart with no work of its own.

Pick the identifier by how long the fact should live. A delivery address is a user_id fact. A mood is a run_id fact. Getting this wrong is not an error you will see: it shows up months later as an assistant confidently telling somebody they were annoyed, once.

Try it yourself

Add a memory under a second user_id and confirm Ravi's filter never returns it.
Store the same sentence under a run_id and under a user_id, then search with each filter.
Try delete_all(run_id="chat-42") and check what survives.

Previousinfer=False: storing what was actually said

You understood something today that you didn't yesterday.