agmiAgent Memory Integrity GitHub

At-rest edit T3

Middle deletion

Remove one record from the middle of the history.

What it looks like in the world: Erasing one inconvenient event from a history that still looks continuous.

attack id delete_middle · version 1 · attacker: store-access

The edit, drawn

T3 Middle deletion

One event in the middle of the history is inconvenient. The attacker removes just that record and points its successor at its predecessor.

Beforeuser AA0A1A2A3A4The edituser AA0A1A2A3A4A2 removed, A3 now follows A1What the agent reads backThe history reads A0, A1, A3, A4.It is shorter, continuous andwrong.

What stops it

A chain: each record carries a tag over the previous record, so a missing link is a broken link.

What does not

Per-record checks, and stores that store the parent id as plain data.

Today, measured 2026-10-07

rejected on read
OpenFang model, tip-persistence fix, Agent Memory reference runtime, SQLite canonical substrate, bucketed row digests, fail-closed open
reported on audit
inspeximus, receipts on, attacker holds the store directory, inspeximus, receipts on, attacker also holds the config home, langgraph-ledger over SqliteSaver, hash-chained ledger, verify_thread audit, memory-blackbox memory.md watcher, agent process alive, scan audit, memory-blackbox memory.md watcher, agent restarted before the scan, scan audit, Atelya Attest, keyed hash chain, verify_chain audit, Atelya Attest, keyed hash chain plus anchored head, verify and consistency audit, CONTINUUM event log, hash chain, verify_events audit, CONTINUUM event log, hash chain plus Ed25519-signed head, attest-verify audit
accepted
LangGraph SqliteSaver, LangGraph PostgresSaver, LangGraph RedisSaver, OpenAI Agents SDK SQLiteSession, LlamaIndex Memory, SQLAlchemy chat store, CrewAI long-term memory, LanceDB dataset, Vertex AI Agent Engine Memory Bank, managed store, edits through the data-plane API, Letta block checkpoint history, Mem0 local Qdrant store, inspeximus, receipts off (default), AtMem 2.3.7, audit chain alone, verify() audit, AtMem 2.3.7, audit chain with an external checkpoint outside the attacker-controlled store directory, verify() audit, acrf-memory-guard, per-entry HMAC over a JSON store

agmi-check --adapter agmi.adapters.langgraph_sqlite:LangGraphSqliteAdapter # runs T1 to T8; this is T3

Every store, this edit

accepted 13

reported 9

rejected 2

Reproduce

pip install agent-memory-integrity
python agmi/full_runner.py --json results/scorecard.json   # every row; the delete_middle column is this page

All 15 edits and attacks · The scorecard