FSRS (Free Spaced Repetition Scheduler)

Platform

Definition

A modern spaced repetition algorithm used in Claude Architect Lab to schedule concept reviews. Tracks four parameters per card: stability (how long memory persists), difficulty (how hard the card is), retrievability (current recall probability), and due date. More accurate than older algorithms like SM-2.

Example Usage

The FSRS algorithm schedules each concept review at the optimal interval to reinforce memory just before forgetting.

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