Answer product-owner round 2: the parent error says the source loads whole at start, and the exit codes name a missing -d folder

README.md

@@ -64,7 +64,7 @@ template holding one from a quoted heredoc or a file. The rest of stdin's rules
 `--name value` and `--name=value` both work, a short flag's value attaches or
 follows (`-n3`, `-n 3`) and short flags bundle (`-hn 3`) — see
 [Decisions](docs/decisions.md#flags-follow-getopt_long); flags go anywhere, `--` ends them. Exit codes: `0` success, `1` runtime error (data
-that fails to load, a lone reference to nothing under `--format`), `2` misuse — a bad flag, an argument
+that fails to load, a missing `-d` folder included, a lone reference to nothing under `--format`), `2` misuse — a bad flag, an argument
 other than a flag, an unreadable stdin, nothing piped in, or a
 template that does not compile. From a checkout:
 `go run ./cmd/fejkdata …`.

internal/datafiles/manifest.go

@@ -196,7 +196,7 @@ func checkParent(index map[string]IndexEntry, p string) error {
 		sibling = p[:dot+1] + parent
 	}
 	if _, ok := index[sibling]; !ok {
-		return fmt.Errorf("parent %q names no entry in this entry's folder; a table in an indexed source links only to a parent in the same index, so to link under another source's table, drop this index and the source loads in New", parent)
+		return fmt.Errorf("parent %q names no entry in this entry's folder; a table in an indexed source links only to a parent in the same index, so to link under another source's table, drop this index, and the source loads whole at start", parent)
 	}
 	return nil
 }