Name the physical end effector
A parallel gripper, a multi-finger hand, and a suction tool do not share one universal action meaning. Identify the hardware and the fields associated with it. If tools change between sessions, retain a configuration reference. A source field called gripper may describe a command, a measured opening, or a binary state depending on the collection.
Define the command convention
State the units, direction, valid range, and meaning of intermediate values where applicable. Explain whether commands set a target, request a change, or represent another control behavior. Document any normalization or inversion performed during export. Do not infer closed versus open from a numerical endpoint without confirmation from source documentation and representative behavior.
Separate command from task outcome
A close command does not prove an object was grasped, and an apparent closed state does not prove a stable hold. Determine which observation or sensor record supports contact and grasp labels. Keep intended operation separate from measured feedback. If an outcome is hidden or unrecorded, mark that limitation instead of turning a control value into a success label.
Inspect transitions and failure cases
Review approach, closure, movement with the object, and release. Include empty grasps, slips, and partial contact when available for the requested task. Check the time relationship between image evidence and gripper records. A sourcing brief should name the end-effector behavior the model needs to learn and the evidence required to evaluate it, rather than requesting an unspecified gripper column.
Review checklist
- Identify end-effector configuration
- Explain value direction and range
- Separate command, feedback, and outcome
- Review empty grasps and releases