Accidentals inside engraved text use proper glyphs, never ASCII 'b'/'#' substitutes

Wherever an accidental appears inside engraved text (figured-bass numerals, roman-numeral labels, chord symbols), it is set with the proper engraved accidental glyph (♭, ♯, ♮) or an approved text substitute used consistently by the house style — never the ASCII letters 'b' (for flat) or '#' (for sharp) left over from plain-text authoring, since 'b' is visually indistinguishable from the pitch name B and '#' is a different-width glyph than a true sharp.

An author types 'b6' intending a flat-six figure, or 'IV#' intending a raised fourth-degree roman numeral, and the literal ASCII characters render as plain text rather than as accidental glyphs, so 'b6' is visually ambiguous with 'note B, figure 6.'

SMuFL defines a dedicated text-flat/text-sharp/text-natural glyph range specifically for accidentals embedded in text contexts (figures, analysis, chord symbols); Gould's general precision-in-symbols principle applies across dynamics, figures, and analytical markup (e.g. for figures).

This rule can be decided from pitches, durations and voices — no layout required. A validator can check it before anything is drawn.