MINT: Musical Intent Representation in Human–AI Co-Creation

Generative music systems commonly receive either natural-language prompts or event-level representations such as MIDI. Prompts carry broad meaning with limited structural precision, while MIDI carries timing and performance events without the compositional reasons that connect them. We present MINT (Musical Intent Language), a domain-specific language for representing musical intent in human--AI co-creation. MINT lets authors write context, materials, harmonic behavior, form, hard requirements, and weighted preferences as inspectable source semantics. Its compiler lowers these declarations to score and performance representations while producing provenance, constraint evidence, and semantic-loss reports. A working harmony vertical slice demonstrates how a composer can describe chord symbol, function, bass, texture, voicing, and register in one program and export MusicXML and MIDI. MINT supplies a concrete interface through which AI systems can assist composition while the creator can inspect and revise the decisions that shape the result. Codes are available at https://github.com/XianzheMeng/musical-intent-lang.