/learn-retain

Spaced retrieval using the FSRS-6 scheduler. Surfaces concepts at optimal intervals for long-term retention.

How it works

1. The learner-model substrate crate tracks FSRS-6 cards per concept
2. learn-retain asks which concepts are due for review
3. Presents a retrieval prompt (explain it again, solve a transfer problem)
4. Updates FSRS-6 state based on performance

Schedule

FSRS-6 calculates the optimal interval between reviews based on:

• Initial memory strength
• Forgetting curve parameters
• Historical performance

Mastery closure gate

learn-retain provides the third mastery condition:

Retention check at ≥ 24h interval after initial mastery claim

The 24h gap ensures the learner isn't passing on short-term working memory.

Usage

/learn-retain                     # review all due concepts
/learn-retain "Rust borrow checker"   # targeted review