action

Definition

The unit of choice an agent makes at each step — the thing a policy outputs. In classic RL it is a discrete move or a continuous control signal; for LLM agents it is a tool call, a shell command, or a click. Two properties set the difficulty: how large the action space is, and whether actions can be undone, since irreversible ones make exploration expensive.

Explainers using this term

• Paper Walkthrough: ZimaBlue — Turning 120,000 Hours of Egocentric Video into Robot SkillZimaBlue: Evolving Generalizable World Action Models through Scalable Video Pre-training
• Paper Walkthrough: GameWAM — Generating the Next Frame and the Next Keystroke TogetherGameWAM: A World Action Model for Video Games
• Paper Explained: Beyond Data Scaling — Why the Backbone, Not the Trajectory Count, Decides Your VLA (VLAct)Beyond Data Scaling: Representation-Centric Continued Pre-training for Vision-Language-Action Models