Detector
Runs on full frames and produces bounding box detections. At least one primary detector (without operate_on) is required in every pipeline.
Classifier (Model Chaining)
Classifiers run on objects detected by a parent model. They must reference a previously defined model using operate_on.
Tracker
An object tracker can be placed anywhere in the models list using type: "tracker". Its position determines where tracking occurs in the inference chain (e.g., between a detector and a classifier).
Active Classes
Use active_classes on a detector to only detect specific classes, ignoring all others. This is useful when your model outputs many classes but you only care about a few.