Analysis response

Field	Type	Description
bpm	float | null	Detected BPM (tempo)
bpm_confidence	float | null	BPM confidence score (0.0–1.0)
key	string | null	Musical key (e.g. "A minor")
key_confidence	float | null	Key confidence score (0.0–1.0)
hz	float | null	A4 tuning frequency in Hz
hz_confidence	float | null	Hz confidence score (0.0–1.0)
lufs	float | null	Integrated loudness in LUFS (EBU R128)
loudness_detail	object | null	Detailed loudness data (see below)
analysis_time	float	Processing time in seconds
cached	bool	true if result was served from cache
analyzer_version	string	Engine version
source_url	string | null	Normalized source URL (for URL analysis)
integrated_lufs	float | null	Integrated loudness in LUFS (e.g. -14.2)
loudness_range	float | null	Loudness Range (LRA) in LU (e.g. 8.3)