Namespace

The structured key a memory is filed under — user, agent, session — and the visibility rule that decides who may read it.

Why it matters in a memory layer

This is the multi-tenancy substrate, and it is a correctness boundary rather than an index hint. Ranking across tenants and trusting similarity to keep them apart is how memory systems leak between users, and the failure is silent: nothing errors, the wrong person's fact simply scores well. Filter on structured keys first, rank second, and assert the leak set is empty rather than assuming it.

Connections

Taught in: Scopes and Namespaces

Used in: The Underrated Default · Scope, Then Rank

Do not confuse with: Retrieval Scoping