Returns the single source of truth mapping each derivation layer to its admiral/metatools function, argument schema, required args, render closure, check ids, and ordering rank. The LLM output space is the cartesian product of this registry; nothing outside it passes [validate_ir()].
Value
A named list; one entry per layer with elements `fn`, `label`, `args`, `required`, `rank`, `checks`, `inputs`, `render`, and - where the layer has optional args with an implied value - `defaults`, a named list of literals or functions of the supplied args. Defaults are applied to `render` input and by canonicalization, so an omitted arg and the same arg stated explicitly are one derivation.
Examples
reg <- aa_layers()
length(reg)
#> [1] 15
reg$assign$fn
#> [1] "dplyr::mutate"