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Set 4 · TRANSFORM

The Date Normalizer

Six dates, six different formats, one correct answer. ISO 8601 as a JSON array, in the order they were given.

Par4
Rules to satisfy4
Prompt budget120 words
AccessHarfi Plus

THE SPEC

Every rule below is checked in code against whatever the model returns. All of them have to hold at once — there are no partial marks, and no opinion involved in the result.

  • Valid JSON array
  • Six ISO dates, original order
  • No markdown fence
  • You didn't write it yourself

WHAT THIS TRIAL TEACHES

The dates that are ambiguous to you are ambiguous to it. Tell it to read the notes in the input rather than infer a format — left alone it picks one and never mentions that it chose.

Knowing the move is not the same as landing it. You still have to write an instruction that makes the model comply, in 120 words or fewer, without writing the answer yourself.

WHY SET 4 IS ABOUT GIVEN INPUT, ONE RIGHT ANSWER

The most useful set here, and the only skill that doesn’t depreciate. Each trial hands you real data, and exactly one output is correct — so the question stops being “did it sound right” and becomes “did it process my data correctly”.

PLAY IT

You write the instruction, never the answer. The parser scores what comes back, and par for this one is 4 strokes. This set is part of Harfi Plus.