Victor Del Puerto logged 699 firings of a hook that reminded Claude Code about relevant memory notes; afterwards the agent opened the note in at most 23.6% of cases. A June paper on TRACE found Mem0 memory still left 57.5% of applicable preference checks violated, in simulated tests.
Runtime PreToolUse hooks do enforce behavior, but in his logs 92% of blocked commands would have run fine. The episode argues that rules which must hold belong in checks, and the rest is advice the agent may never open.