The AI Taxonomy.
Terms  /  Memory & State  /  Memory Fidelity
03 · Memory & State

Memory Fidelity

The accuracy and completeness of what a system retains over time. The opposite of Context Rot.

Memory Fidelity measures whether what the system remembers is actually correct and complete. High Memory Fidelity means the system's stored knowledge accurately reflects reality — decisions are recorded with their reasoning, facts are current, and nothing important has been lost to compression. Low Memory Fidelity means the system's memory has degraded: it remembers the conclusions but not the reasoning, retains outdated facts alongside current ones, or has summarized nuanced decisions into oversimplified rules.

Example
A team uses a memory-enabled agent for six months. They run an audit and find that 94% of stored facts are still accurate, all major decisions include the original reasoning, and outdated information is properly flagged. That's high Memory Fidelity. Compare this to another team whose agent has compressed six months of work into a 2,000-token summary that says things like "uses PostgreSQL" (they migrated to MongoDB two months ago) and "deploys to AWS" (they moved to GCP last month). That's low Memory Fidelity — the memory exists but it's wrong.

More in Memory & State

Context Anxiety

The dread of re-explaining everything every session because the system has no persistent memory.

Ghost Knowledge

Facts that exist in the system but can't be traced to an author or source.

Context Rot

Deterioration of an agent's understanding over time due to limited memory and compaction.

State Loss

Failure to maintain awareness of prior actions.

Context Continuity

Seamless persistence of knowledge across sessions — the user never re-explains. The cure for Context Anxiety.

Provenance Clarity

Every fact in the system is traceable to its author, source, and reasoning. The cure for Ghost Knowledge.

Recall Precision

The system retrieves exactly the right context at the right time — no noise, no gaps.

State Awareness

The system's ability to maintain and use awareness of prior actions within a session. The opposite of State Loss.