Answer prose round 1: errNoData, the reads paragraph and the changelog entry read in one pass, the Library section shows the import block for one locale, and the decisions state why New checks no reads and which goal the embed serves

todo.md

@@ -182,7 +182,7 @@ Pick the ten from a published ranking of languages by total speakers, such as Et
 
 ### 185. Seat a panel of the README's audience personas to pull data in through the module API and build a custom CLI, and fix what it names.
 
-Needs item 184; 0.1.0 is not cut before it. Carries out the decision "The shipped data is Go packages a library imports by choice, and the CLI carries every one, from 0.1.0". Seats: the Go test author, the bulk fixture author, a custom CLI's builder, and a data author with a `-d` folder and the replace flag, each in a scratch Go module against the checkout or a pre-release tag. Bench the geo packages' names, `data.Modules()`, the error naming the import set, and the `.fejkdata.json` manifest a data author writes by hand. Decoding the manifest is most of `New`'s cost (about 0.55 ms and 2449 allocations on 2026-10-10, 2864 allocations once each module carried its own). An entry lists every path below its category, its linked tables' paths too, so `geo.*.region` repeats its whole family. An entry holding only its own paths, with `List` composing a family from the entries naming it as `parent`, would shrink it. Record the ruling in `docs/`.
+Needs item 184; 0.1.0 is not cut before it. Carries out the decision "The shipped data is Go packages a library imports by choice, and the CLI carries every one, from 0.1.0". Seats: the Go test author, the bulk fixture author, a custom CLI's builder, and a data author with a `-d` folder and the replace flag, each in a scratch Go module against the checkout or a pre-release tag. Bench the geo packages' names, `data.Modules()`, the error naming the import set, and the `.fejkdata.json` manifest a data author writes by hand. Decoding the manifest is most of `New`'s cost (about 0.55 ms and 2449 allocations on 2026-10-10, 2864 allocations once each module carried its own manifest). An entry lists every path below its category, its linked tables' paths too, so `geo.*.region` repeats its whole family. An entry holding only its own paths, with `List` composing a family from the entries naming it as `parent`, would shrink it. Record the ruling in `docs/`.
 
 ### 16. Add locale categories: company, phone, finance, vehicle, words.
 
@@ -491,7 +491,7 @@ Reread: `readField`'s note on clearing the pick (`render.go`), `pickKey.under`,
 
 ### 195. Parse each builtin argument once, in `checkArgs`, and hand `prep` and `proveNumber` the parsed value.
 
-Applies "Validate data and build DTOs as early as possible" in `~/.claude/principles/technical-principles.md`. Today `checkArgs` (`internal/builtinfunc/builtins.go`) checks an argument, then `prep` and `proveNumber` parse it again through `atoi`/`atof`, which panic, as do `layout.go`, `transform.go` and `calc.go`; two parsers can drift, and a drift panics at compile instead of failing the load.
+Applies "Validate data and build DTOs as early as possible" in `~/.claude/principles/technical-principles.md`. Today `checkArgs` (`internal/builtinfunc/builtins.go`) checks an argument, then `prep` and `proveNumber` parse it again through `atoi`/`atof`, which panic on bad input; `layout.go`, `transform.go` and `calc.go` call them too; two parsers can drift, and a drift panics at compile instead of failing the load.
 
 ### 112. Check a calc's field operands where its template resolves, beside its name operands, once item 36 reports every mistake at once.