Scored across 5 tools
Each tool occupies a distinct slot: search (brain_recall), ingest (brain_distill), write a fact (brain_remember), session lifecycle (brain_session), and health/diagnostics (brain_status). Every description ends with an explicit 'Not for X (brain_Y)' boundary statement, so an agent has no path to confuse one with another.
All five tools share a strict `brain_` prefix followed by a single lowercase token, which reads as a coherent namespace. Minor deviation: recall/remember/distill are verbs while session/status are nouns, so the pattern is prefix-consistent but not uniformly verb_noun.
Five tools is tight and each earns its place: with the memory domain you need read, write, ingest, session boundary, and diagnostics, and nothing is redundant. brain_session reasonably bundles start/end into one phase-parameterised tool rather than splitting into two.
The read/write/ingest/lifecycle/diagnostic loop is fully closed, including partial-failure reporting and duplicate/contradiction handling. The gap is that memory is strictly append-only: there is no forget/prune/retract or explicit edit path, so a user cannot remove an obsolete item, and brain_status hints at 'maintenance' for which no tool exists.