What is unreal-castle-builder?

A procedure for building a simple castle or fortress prototype in Unreal Engine from basic geometric shapes.

Use it to create varied castle layouts, sizes, colours, rotations, and positions, then list the generated actors for verification.

It provides the commands and checks needed to create the castle and confirm that its actors exist in the current level.

How runeape-sats/unreal-mcp configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to runeape-sats/unreal-mcp. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file

curl -O https://raw.githubusercontent.com/runeape-sats/unreal-mcp/main/.github/skills/unreal-castle-builder/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/runeape-sats/unreal-mcp

Made for: Claude Code.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/runeape-sats/unreal-mcp/unreal-castle-builder/github.svg)](https://agentmods.dev/skills/runeape-sats/unreal-mcp/unreal-castle-builder)

Your own site

<a href="https://agentmods.dev/skills/runeape-sats/unreal-mcp/unreal-castle-builder"><img src="https://agentmods.dev/badge/skills/runeape-sats/unreal-mcp/unreal-castle-builder/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.

Your own site · 80×15

<a href="https://agentmods.dev/skills/runeape-sats/unreal-mcp/unreal-castle-builder"><img src="https://agentmods.dev/badge/skills/runeape-sats/unreal-mcp/unreal-castle-builder.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 55 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 591 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.

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.

Model	Per session	Once invoked
Fable 5.1	$0.00055	$0.00591
Opus 5.5	$0.00022	$0.00236
Sonnet 5.5	$0.00011	$0.00118
Haiku 4.5	$0.00006	$0.00059

Measured 2mo ago against content hash 3342d57eda93, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

unreal-castle-builder 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 2mo 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.

.github/skills/unreal-castle-builder/SKILL.md · 40 lines

How it starts

The opening of the file, as written. The whole thing — 40 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Unreal Castle Builder

When To Use

Build a quick castle or fortress prototype in Unreal Engine from basic shapes.
Teach another agent how to drive this repository through the direct CLI instead of MCP tool discovery.
Verify that a generated castle actually exists in the current level by listing actors.

Procedure

Inspect the CLI entrypoint first. Run unreal-mcp-cli --help. If the editable script is not installed yet, run .\.venv\Scripts\python.exe unreal_cli.py --help instead.
Inspect the castle-specific commands. Run unreal-mcp-cli create-basic-castle --help and unreal-mcp-cli list-level-actors --help. Pay attention to the --layout, --size, --palette, --yaw, and --origin options so the castle can vary without changing the required actor set.
Review the shared castle layout in examples/castle/assets/castle-plan.json.
Create the castle with a unique prefix so verification is unambiguous. Example: unreal-mcp-cli create-basic-castle --prefix SkillCastle --layout courtyard --size grand --palette sandstone
Verify the result by listing actors with the same prefix. Example: unreal-mcp-cli list-level-actors --kwargs "filter=SkillCastle max_results=40"
Run the dedicated verification command. Example: unreal-mcp-cli verify-basic-castle --prefix SkillCastle
If the user asks for cleanup or a rebuild, inspect unreal-mcp-cli reset-basic-castle --help and use it with the same prefix.
Report the created actor count, any missing labels, and whether the castle is complete.

Expectations

Do not save the level unless the user asks for it.
Prefer a unique prefix per run to avoid collisions with prior castle attempts.
Use named variation presets when the user asks for a different silhouette or mood; use --origin and --yaw when the user asks for a different placement.
If verification fails, report the missing labels and stop instead of guessing.

Read the full file on GitHub · 40 lines

Files

What ships with it

1 file 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.

references/castle-workflow.md 1.0 KB

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.

2mo ago First seen · 40 lines · 55 tokens per session scan A 3342d57eda93

Subscribe to this mod's changes

unreal-castle-builder is a skill published in the GitHub repository runeape-sats/unreal-mcp (47 stars, last pushed 7mo ago), licensed MIT. It adds 55 tokens to every session and 591 once invoked, about $0.0002 per session on Opus 5.5. 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.

Game development genai mcp-server unreal-engine-5

unreal-castle-builder next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
unreal-castle-builderruneape-sats/unreal-mcp	Skill	47	7mo ago	MIT	A	55	Claude Code
level-actorskevinpbuckley/VibeUE	Skill	823	today	MIT	A	64	Claude Code, Codex
vibeuekevinpbuckley/VibeUE	Skill	823	today	MIT	A	82	Claude Code, Codex
materialskevinpbuckley/VibeUE	Skill	823	today	MIT	A	95	Claude Code, Codex
sound-cueskevinpbuckley/VibeUE	Skill	823	today	MIT	A	62	Claude Code, Codex
gameplay-tagskevinpbuckley/VibeUE	Skill	823	today	MIT	A	57	Claude Code, Codex
ue-mcp-animationdb-lyon/ue-mcp	Skill	486	today	MIT	A	85	Claude Code, Codex

unreal-mcp: Skill for Claude Code