godot-state-machine-advanced — Claude Code skill: HSM and pushdown

What godot-state-machine-advanced does

The skill ships a set of GDScript files for complex character and AI behavior in Godot. You get a hierarchical base that forwards physics and input down to sub-states, a pushdown stack for interrupt overlays like pause or menus, a context object for passing data between states, a guard that blocks illegal transitions, an AnimationTree syncer, concurrent state machines, a loader that reads state definitions from .tres resources, a history logger and an auto-transition timer.

A decision tree maps the need to the machine: flat FSM, HSM, pushdown, concurrent or utility cost polling. The scripts are declared the source of truth, and copying inline samples is discouraged because an earlier body called exit() twice and dropped resume messages. For hierarchy, pushdown and guards you are told to read hsm_hierarchical_base.gd, hsm_pushdown_stack.gd and hsm_transition_guard.gd.

Depth is the hard limit. Nesting beyond three levels is called state spaghetti, and the skill points you toward a behavior tree or utility AI instead. Every push_state needs a matching pop_state or the stack overflows. The license is LGPL-3.0, so if you ship a closed-source game, check what that means before the code goes into a release build.