How to use
- Copy the installation command and review the source package before installing it in your own agent environment.
- Check the source document for required tools, credentials and supported hosts.
- Describe your input and desired deliverable; review the output against the source material.
npx skills add https://github.com/thedivergentai/game-design-agentic-skills --skill bevy-character-movementBefore you start
- Installation does not include a model subscription, API allowance or permission to access your files.
- Repository stars and installation counts describe activity, not an independent quality or security test.
Rendered from the source repository. Headings, examples, code, tables, links, and referenced images are preserved.
Bevy character movement
When to use
Load this when a Bevy app needs a player or actor that moves in discrete steps (walk, jump feel, ground check) and you need the ECS shape before any solver code exists. Coyote time and a jump buffer are design notes. They are not a node port.
ECS shape
- Components own pose and intent: position, velocity, and a jump-buffer or coyote timer as data. The Quick Start ECS page shows components as Rust structs that derive
Component. - Resources own clocks and tuning shared by every mover.
bevy::time0.20.0 documentsTime,Fixed(fixed timestep clock), andVirtual. - Systems read intent and write velocity or position. Register them on the fixed schedule, not on a per-node physics callback.
- Schedule:
run_fixed_main_schedulerunsFixedMainfrom virtual time (bevy::time0.20.0). Order dependent systems with.chain()(ECS page). Do not paste a Godot physics-process function.
Coming from Godot
| Godot idea | Bevy idiom |
|---|---|
| Body that you move yourself | Entity with movement components and a system |
| Step that should stay stable when frame time changes | System on the fixed timestep (Fixed / FixedMain) |
| Coyote time, jump buffer | Timer data on the entity or a small resource, consumed by the movement system |
| Collision response | Collision response belongs on bevy-physics-3d. |
Scope
- Check the
bevy0.20.0 crate docs for a character-controller type before writing one. The feature list has no physics solver. - Do not call
move_and_slide,_physics_process, orCharacterBody2D. - Ground detection, shape casts, and collision layers are unverified. Do not invent query APIs.
Expert Knowledge Delta
Target: Bevy 0.20+.
Core ECS types: Component, Resource, Query, Commands, Startup, Update, Fixed / FixedMain (bevy::time), .chain(), Plugin, DefaultPlugins, MinimalPlugins. Messages and observers are an ownership slot. See bevy-events-messaging for their APIs. Systems run in parallel unless .chain() orders the ones that conflict.
Who owns state
| Piece | Owner | Who may mutate | Schedule |
|---|---|---|---|
| Data on one entity | Component | One system via Query | Update or FixedMain |
| One value for the whole app | Resource | One system | Startup to insert, then the schedule that reads it |
| Spawn | Commands | The spawning system | Startup for the initial world; later schedules for runtime spawn |
| Order that must not race | .chain() | The chained systems only | Same schedule |
| Plugin boundary | Plugin | build registers systems and resources | Before the app runs |
Borrow rule: two systems that both mutably query the same component must be ordered (.chain()) or split so only one writes. Unrelated systems stay parallel. That is the ECS page rule, not a guess at a system-set API.
Decision
| If you need | Do this | Do not |
|---|---|---|
| Per-entity data | Component + Query | A Godot node script |
| App-wide config or clock | Resource | Copy the value onto every entity |
| Stable simulation step | FixedMain and the Fixed clock | Tie simulation to raw frame Update |
| Startup spawn | Commands in Startup | Spawn from a render system |
| Cross-system notice that is not shared state | Message or observer slot in bevy-events-messaging | A new event type invented in this file |
| An API outside the documented set | Check the official docs first | A made-up crate or API |
Load references/ecs-ownership.md for the ownership table.
NEVER
- Do not pin
/0.20.0/in docs URLs. WHY: links stay onlatest; the 0.20 target is stated once in prose. - Do not step locomotion on raw
Updatewhen the step must stay stable. WHY:bevy::timedocumentsFixedandrun_fixed_main_schedule(FixedMain) for a fixed clock. - Do not call
move_and_slide,_physics_process, orCharacterBody2D. WHY: those are Godot types. This skill only owns ECS movement data. - Do not invent a character-controller or shape-cast API. Check the
bevycrate docs for a controller type before writing one. - Do not mutably query the same movement component from two unordered systems. WHY: systems run in parallel unless
.chain()orders them.
Reference
docs.rs links use the unversioned latest permalink. The library pin on bevy-master stays 0.20.0.
Official Documentation
- Migration guides - Unversioned hop index.
- bevy crate - Unversioned API index.
- Examples - Example tree on the
latestbranch. - Quick Start: ECS - Entities,
Component, systems,Query,Commands, and.chain(). - bevy::time -
Time,Fixed, andrun_fixed_main_schedule(FixedMain).
Related Skills
Prerequisites
- bevy-master - ECS ownership, schedules, and which Bevy skill to load.
Complements
- bevy-physics-3d - Collision and physics solvers. Player motion stays in this skill.
- godot-characterbody-2d - Equivalent Godot skill. Do not import Godot types.
Downstream / consumers
- Genre skills cover loop and encounter design.
Master
- bevy-master - Bevy router.

