state-trees

state-trees is a skill for Claude Code, Codex from kevinpbuckley/VibeUE. It costs 72 tokens per session (6,078 once invoked), scanned A, original, MIT.

A tool for creating and editing StateTree assets in Unreal Engine, a game-development system. StateTree is a visual hierarchy of states, tasks, transitions, conditions, and property bindings used to control game or AI behavior.

In plain words
What is it for?
Use it to build AI behavior, add states and transitions, configure tasks and conditions, bind task properties, and set up Utility AI considerations.
Why use it?
It organizes complex character and game logic into connected states, making behavior easier to inspect and change. Blueprint-based StateTree tasks require separate Blueprint editing support.

Skill for Claude CodeCodex

Written for no agent in particular: nothing here depends on one. Also seen: mentions Claude Code; mentions Codex.

Good fit Use it to build AI behavior, add states and transitions, configure tasks and conditions, bind task properties, and set up Utility AI considerations.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/kevinpbuckley/vibeue/state-trees
Install

Getting it into your agent

One page per mod, every tool's command on it. A separate URL per tool would split the same page into five that compete with each other.

Any agent
npx skills add kevinpbuckley/VibeUE --skill state-trees
Clone the repo
git clone --depth 1 https://github.com/kevinpbuckley/VibeUE

Made for: Claude Code, Codex.

Wrote this? Show the measurements

A badge with what this costs and how it scanned, read live from this page, so it follows the numbers instead of freezing them. Markdown for a README, HTML for a documentation site or a project page.

agentmods badge for state-trees

README.md
[![agentmods](https://agentmods.dev/badge/skills/kevinpbuckley/vibeue/state-trees/github.svg)](https://agentmods.dev/skills/kevinpbuckley/vibeue/state-trees)
Your own site
<a href="https://agentmods.dev/skills/kevinpbuckley/vibeue/state-trees"><img src="https://agentmods.dev/badge/skills/kevinpbuckley/vibeue/state-trees/github.svg" alt="Measured on agentmods" height="20"></a>

Or the 80×15 button, for a site that already has a row of RSS and ATOM ones. Only the verdict fits; the numbers stay here.

agentmods 80×15 button for state-trees

Your own site · 80×15
<a href="https://agentmods.dev/skills/kevinpbuckley/vibeue/state-trees"><img src="https://agentmods.dev/badge/skills/kevinpbuckley/vibeue/state-trees.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 72 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 6,078 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. A grade says what 26 rules found in the file — not that it is safe. Third-party audits
  • NVIDIA SkillSpector warn 7 Sept 2026
SkillSpector: 1 finding, up to high

These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →

  • high Output Handling · line 367
    Model output is used without validation or sanitization. Unvalidated output injected into downstream contexts (SQL, shell, HTML) enables injection attacks and arbitrary code execution.
    Fix: Validate and sanitize all model output before using it in downstream contexts. Use parameterized queries for SQL, shell quoting for commands, and HTML encoding for web output.
How audits are shown
Origin original No closer match found in the catalogue.
Token cost

What it costs to keep this loaded

Counted locally with the o200k_base tokenizer, which is exact for GPT models; Claude uses its own tokenizer and its counts differ. Treat this as one consistent yardstick across the catalogue rather than a bill. Prices are per million input tokens.

ModelPer sessionOnce invoked
Fable 5.1 $0.00072 $0.06078
Opus 5 $0.00036 $0.03039
Sonnet 5 $0.00014 $0.01216
Haiku 4.5 $0.00007 $0.00608

Measured 10d ago against content hash 8acba00762a7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-10, from the pricing page.

Security

Grade A, and why

state-trees scanned grade A with 0 findings against 26 rules in 11 categories — prompt injection, anti-refusal, data exfiltration, privilege escalation, supply chain, agent snooping, system-prompt leakage, SSRF and excessive agency — measured 10d ago.

A static scan of the body, not an audit. Every finding is printed with the line that produced it so you can judge whether it matters here. A mod is markdown that instructs an agent; that is exactly why what it instructs is worth reading.

Nothing flagged

None of the 26 patterns this scan looks for appear in this file: no shell pipes, no recursive deletes, no credential paths, no hidden text, no instruction-override or anti-refusal phrasing, no agent-config snooping. That is not a guarantee, it is the absence of the things that are checkable.

Content/Skills/state-trees/SKILL.md · 510 lines

How it starts

The opening of the file, as written. The whole thing — 510 lines — stays where its author put it; the contents beside it link to each section on GitHub.

🧠 Brains complement: IF an unreal-engine-skills-manager tool (external MCP) exists in this session, call it with {action: "load", skill: "ai-and-navigation"} for UE domain knowledge on this topic — correct APIs, architecture, best practices — and treat it as the rubric for any review / "best practices" question. If no such tool is available (e.g. running under Claude Code or Codex without that MCP), skip this line entirely and proceed with this skill alone — do NOT attempt the call.

StateTree Skill

StateTree is Unreal Engine's hierarchical state machine system for AI behavior and game logic. This skill covers creating and editing StateTree assets via unreal.StateTreeService.

⚠️ StateTree Blueprint Tasks Require the Blueprints Skill

StateTree Tasks prefixed STT_ (e.g. STT_Rotate, STT_Move) are Blueprint assets. They are edited with BlueprintService, not StateTreeService.

Always load the blueprints skill when the user asks to:

  • Add or edit variables on an STT task
  • Override functions (GetDescription, ReceiveLatentTick, ReceiveLatentEnterState, etc.)
  • Add Blueprint nodes or connect pins inside an STT task graph
  • Inspect or modify STT task logic

Also load the blueprint-graphs skill when the task involves node wiring, timers, custom events, pin names, or EventGraph layout inside an STT_* Blueprint.

StateTreeService  → edits the StateTree ASSET (states, tasks list, transitions, parameters)
BlueprintService  → edits the STT Blueprint CONTENT (variables, function graphs, node wiring)

Load the blueprints skill (via the engine AgentSkillToolsetGetSkills, see the vibeue skill) before writing any code that touches an STT_* Blueprint's internals.

If the request mentions timers, delayed completion, event callbacks, or screenshots of Blueprint graphs, also load the blueprint-graphs skill:

call_tool(toolset="ToolsetRegistry.AgentSkillToolset", tool="GetSkills", args={"skills": ["blueprint-graphs"]})

Read the full file on GitHub · 510 lines

Files

What ships with it

6 files beside SKILL.md in the same directory: the scripts, references and assets a skill reads on demand. Not counted in the per-session cost; read them before you install if any of them is executable.

Changes

What this file has done since we first saw it

Hashed on every crawl. A supply-chain change to an agent config is a question of when, not whether, so the history is kept rather than the latest state alone.

  1. 10d ago First seen · 510 lines · 72 tokens per session scan A 8acba00762a7

Subscribe to this mod's changes

state-trees is a skill published in the GitHub repository kevinpbuckley/VibeUE (662 stars, last pushed 6d ago), licensed MIT. It adds 72 tokens to every session and 6,078 once invoked, about $0.0004 per session on Opus 5. A static security scan graded it A with 0 findings. No closer match exists in the catalogue, so it is treated as the original; first seen 2026-08-30.

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