physics-3d-collision

An agent skill by Unity-Technologies, from Unity-Technologies/unity-agent-plugin. Tags: design, games, unity.

What it does

3D PhysX collision and trigger diagnostics for MonoBehaviour-based Unity projects. Primary scope: OnCollisionEnter / OnTriggerEnter not firing, objects passing through each other, Physics.Raycast missing, ragdoll explosion, AddForce stops working after settling, MeshCollider rules, and similar 3D PhysX symptoms. Adjacent topics (2D physics, OTS / Unity Physics package): provides a brief best-effort answer with a scope disclaimer and a documentation link, rather than refusing outright. When dedicated specialist skills (physics-2d, physics-dots) are installed, those should handle their respective domains and this skill defers to them.

Install

With the skills CLI, which installs into Claude Code, Codex, Cursor and other agents:

npx skills add Unity-Technologies/unity-agent-plugin --skill physics-3d-collision

Or copy the skill folder into Claude Code's skills directory by hand (~/.claude/skills for every project, or .claude/skills inside one):

git clone --depth 1 https://github.com/Unity-Technologies/unity-agent-plugin
cp -r unity-agent-plugin/skills/physics-3d-collision ~/.claude/skills/physics-3d-collision

Safety box score

Not rated yet. A safety box score grades what a skill and its scripts can reach on the machine of whoever installs it, across eight categories from shell execution to secrets access. Anyone can request one from this page; it is saved for everyone. How the score works.

Source

Repository

Unity-Technologies/unity-agent-plugin (all skills from this repository)

Path

skills/physics-3d-collision/SKILL.md

Branch

main

Updated

2026-09-22

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