Last weekend my assistant lost track of four requests from a long conversation. The session compacted its history, kept the gist, dropped the specifics. I reconstructed them myself.
My team and I run agents that hand work off between sessions and each other. Handoffs are where detail goes to die: the receiver gets the summary, not the raw context. Compaction is just the automated version.
Briefs and written handoffs help, but they are paperwork around a forgetful core. The real fix is memory that outlives the session, durable and structured, surviving compaction by design. An agent without long-term memory starts over every morning.
So I ask one question of agent platforms now: show me the memory. Not the context window, the memory.
How does your agent remember last week?