Use a deployed VLAC-style vision-language-action critic service to evaluate task progress, compare current observations against a reference image, and judge task completion from robot camera frames. Use when the agent needs external progress supervision, completion verification, failure detection, or image-based task-state comparison for Piper, Unitree G1, or Unitree Go2.
Use this skill when a robot task needs an external judge instead of relying only on hand-written heuristics.
This skill is about using an already deployed critic service, not deploying the service.
The VLAC critic can compare:
and return progress or completion-related judgment.
This is useful for:
For the FastAPI service in this stack:
POST /criticimagereference_imagetask_descriptionImportant:
image and reference_image must be sent in the same request{
"image": "<base64_or_url_or_path>",
"reference_image": "<base64_or_url_or_path>",
"task_description": "..."
}
This skill owns:
/criticThis skill does not own robot SDK discovery. Use abotclaw-sdk-discovery to learn how each robot provides camera frames.
Use the critic when:
abotclaw-sdk-discovery to learn how the target robot exposes camera frames.The current observation can come from any robot in the fleet:
Choose the camera that best reflects task progress.
Examples:
A reference image may come from:
abotclaw-memoryGet the correct host and port from service.md.
curl -s -X POST <VLAC_BASE_URL>/critic \
-H 'Content-Type: application/json' \
-d '{
"image":"<current_frame>",
"reference_image":"<reference_frame>",
"task_description":"Put the bowl back into the white storage box."
}'
imageUse the robot's current frame.
reference_imageUse an image that represents the expected target state or a meaningful comparison state.
task_descriptionKeep it concrete and visual.
Better:
Worse:
Treat the critic output as task supervision, not absolute truth.
Possible uses:
The image source does not have to come from the same robot that originally planned the task.
Examples:
This skill works well with abotclaw-memory:
reference_imageUse the critic to reduce ambiguity in real-world execution, especially when success is easier to see than to hand-code.
Do not pretend the critic is a robot controller. It is a supervisor and evaluator.