One option from a named set, 1..255 options.
The encoding obligation is the CALLER's (§8B, docs/adr/0021):
criteria[id] is the only thing that differentiates one option from another to
the model. Passing the id itself, an empty string, or one value repeated is
schema-valid, returns HTTP 200 and a well-formed distribution — and ranks at
chance (measured: 17 apples described by consequence, 0/1/0 described by id).