FLX-1004: mapping key cannot be coerced to a string

Family: canonicalisation (the 1000 band)

KERNEL-SPEC §2.1 coerces the non-string mapping keys PyYAML can produce -- bool, int, null, Decimal -- to their JSON spelling. A key of any other class has no defined spelling and is refused rather than guessed.

Look it up offline

$ fluxsim explain FLX-1004

Every code is listed in the error index.