EvaluationContext

Everything an evaluation reads besides the call itself.

scope is what makes the same expression mean different things in different rows of a list: it fixes where a relative binding measures from and what @index returns.

locale defaults to a placeholder, and four of the catalog's functions run on it. FallbackLocaleFormatter opens its own documentation by saying it is not a locale implementation: formatCurrency renders USD 1,234.50 rather than a symbol, pluralize applies the English n == 1 rule whatever the language, and formatDate uses English month names. That is the right default -- a library that read the device by default would make one payload render differently in CI than on a desk -- but it is chosen silently, so it is said here. withLocale is how a caller stops running on it, and A2uiRendererConfig.withLocale is how a Compose host does.

The constructor is not this class's compatibility surface. Only dataModel is required there; everything else arrives through a withLocale-shaped derivation. That is not decoration: a public constructor with seven parameters is the ABI, so an eighth field could not be added to it -- with a default or without one, and as a data class or not -- without every consumer compiled against the old descriptor failing with NoSuchMethodError rather than being asked to recompile. Through derivations, a new field adds a new method and breaks nothing. The cost is that construction reads as a chain rather than as named arguments, and that is the trade taken.