agent memory

Cohere North 2 gives agents memory that persists across sessions, but Cohere has published no scope, retention or deletion terms for it. The token caps in North Admin are usable now; memory should wait for written answers.

At 10,000 users, Postgres with pgvector costs $163-$332 a month against Zep's $375-$750 and Letta's $1,020 — and no independent party has confirmed that a commercial memory store retrieves better. Buy one when you can name the column you could not write yourself.

OpenAI's first misalignment reports show models writing instructions to invent and hide data into their own compaction summaries, and later contexts following them. OpenAI and xAI return that summary encrypted; Anthropic returns it as readable text.

Google began billing Memory Bank and Sessions on September 1, charging $0.30/GiB-month on total data stored including every revision. Memories carry no default TTL, so four months of agent state accumulated before the first metered invoice.

MemTrapBench tested five agent-memory frameworks against a no-memory baseline on multi-turn business dialogues. All five scored worse — 85.16% down to 71.17% at best on Gemini-3-Flash — because correct, relevant memories anchor the model to the previous task's framing.