#+TITLE: ADR-3: Drill direction
#+DATE: 2026-04-30
#+STATUS: Accepted

* Context

=gloss-drill-export-all= tags every entry for =org-drill=. The card
type controls which direction(s) the drill quizzes — term-to-definition
(recognition), definition-to-term (recall), or both.

* Decision

Set =:DRILL_CARD_TYPE: twosided= on every exported entry.
=org-drill='s twosided card type alternates direction on consecutive
visits, so a single entry quizzes both directions over time.

No per-entry override in v1. Every entry exports as twosided.

* Consequences

*Positive.*

- Tests both recognition and recall over time without doubling the
  deck size — one entry, both directions, alternated by =org-drill='s
  scheduler.
- No per-entry decision burden during =gloss-add= or
  =gloss-drill-export=.

*Negative.*

- Some terms make more sense one-directional. A user who saved
  "SBIR" → "Small Business Innovation Research" probably wants
  recognition only (acronym → expansion), not recall (expansion →
  acronym). v1 doesn't accommodate this.
- A future v2 may want a per-entry =:DRILL_CARD_TYPE:= override or a
  defcustom for the default. Both are additive changes.

* Alternatives Considered

*=:DRILL_CARD_TYPE: simple= (term → definition only).* Rejected:
half the value of the cards, and the user can always skip-back
during drill if they don't want the reverse direction.

*Two cards per entry, one each direction.* Rejected: doubles the
deck size; adds maintenance burden when an entry is edited (now
two cards diverge).

*Cloze cards.* Rejected: needs a marked deletion in the body, which
fights the "save once, drill forever" promise.