WebXSkill

Web agents can navigate a page, but ask them to repeat a checkout flow they already completed and they start from scratch every time. WebXSkill is a skill learning framework where web agents extract reusable skills from synthetic trajectories, each pairing a parameterized action program with step-level natural language guidance. Two deployment modes let the agent either auto-execute skills as atomic tool calls (grounded) or follow them as step-by-step instructions while retaining autonomy to adapt (guided). On WebArena, WebXSkill improves task success by up to 9.8 points over baselines. On WebVoyager, grounded mode reaches 86.1%, a 14.2-point gain, and skills even transfer across environments.