Good Prompts Encode Understanding
Writing good spaced repetition prompts is not a mechanical task. It is an act of understanding the process of decomposing knowledge into its atomic components reveals how well you actually grasp it.
"Writing good prompts feels surprisingly similar to translating written text. You're asking: which words, when read, would light a similar set of bulbs in readers' minds?" Andy Matuschak
Matuschak identifies five properties of effective retrieval practice prompts: they should be focused (one idea at a time), precise (not vague), consistent (lighting the same mental bulbs each time), tractable (you can almost always answer correctly), and effortful (not trivially inferable). These properties are not arbitrary rules they emerge from how memory actually works. A vague question produces vague retrieval, which fails to strengthen the specific neural pathways you care about. A yes/no question requires so little effort that it creates shallow understanding you can parrot but not apply.
The deeper insight is that prompt-writing skills mirror understanding skills. "Break things up into atomic facts. Build rich hierarchies of interconnections. Don't put in orphan questions." These are not just rules for Anki cards they are descriptions of what it means to truly understand something. When Nielsen says that constructing a card is "itself nearly always a form of elaborative encoding," he means that the act of deciding what to ask and how to phrase it forces you to think through the material more carefully than passive reading ever would.
There is a practical anti-pattern to watch for: the compulsion to economize on prompts. People treat each card as having a per-unit cost and try to write fewer, broader questions. But as Matuschak notes, "the number of units of raw knowledge is fixed, a constant of the territory. When you write coarser prompts, you're just making the material harder to review." An easy prompt consumes only 10-30 seconds across an entire year. Write more than feels natural.
Takeaway: Treat prompt-writing as a skill to develop to virtuoso levels the quality of your prompts directly determines the quality of your understanding.
See also: Spaced Repetition Turns Reading Into Remembering | Writing Is Thinking Made Visible | Quality Comes From Reps Not Talent