Constant MAX_DEPTH 

pub const MAX_DEPTH: usize = 32;

Container nesting, variants included. The specification allows 64 (32 arrays + 32 structs); NetGet allows 32, because a decoded value becomes JSON inside an event, and the event and handler pipeline bounds JSON at 64 levels: a 64-deep value plus its event’s own wrapping does not fit, and was refused there instead of here.