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Set 2 · SCHEMA

The Typed Field

One book as JSON. `year` must be a number, not a string in quotes — machines care about the difference even when people don't.

Par4
Rules to satisfy3
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 with keys title, year, tags
  • No markdown fence
  • You didn't write it yourself

WHAT THIS TRIAL TEACHES

Types don't survive politeness. Say “a number, not a string in quotes” — machines care about the difference even when readers don't.

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 2 IS ABOUT MACHINE-READABLE

The step from “looks right” to “parses”. Every rule here runs a real parser, so output a downstream system would reject fails here too — a stray code fence is a failure, not a formatting quibble.

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.