What is update-prefab?

A Unity editor workflow for updating a reusable game-interface asset, called a prefab, to match its design in Figma, a collaborative design tool.

It compares the design and prefab, then updates text, colors, sizes, fonts, layout, hierarchy, and children; it does not change sprites.

It brings design changes into Unity while preserving manual Unity-side adjustments.

How chav0/UnityFigmaMCP configures Claude Code

Reuse

Borrowing it

Nothing to install: this file belongs to chav0/UnityFigmaMCP. 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/chav0/UnityFigmaMCP/main/.claude/skills/update-prefab/SKILL.md

Clone the repo

git clone --depth 1 https://github.com/chav0/UnityFigmaMCP

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/chav0/unityfigmamcp/update-prefab/github.svg)](https://agentmods.dev/skills/chav0/unityfigmamcp/update-prefab)

Your own site

<a href="https://agentmods.dev/skills/chav0/unityfigmamcp/update-prefab"><img src="https://agentmods.dev/badge/skills/chav0/unityfigmamcp/update-prefab/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/chav0/unityfigmamcp/update-prefab"><img src="https://agentmods.dev/badge/skills/chav0/unityfigmamcp/update-prefab.svg" alt="Reviewed on agentmods" width="80" height="20"></a>

Per session 110 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 1,478 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	$0.00110	$0.01478
Opus 5.5	$0.00044	$0.00591
Sonnet 5.5	$0.00022	$0.00296
Haiku 4.5	$0.00011	$0.00148

Measured 24d ago against content hash c9c7a4e4c2ee, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

update-prefab 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 24d 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.

.claude/skills/update-prefab/SKILL.md · 163 lines

How it starts

The opening of the file, as written. The whole thing — 163 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Update Prefab — Sync with Figma Source

This skill compares an existing Unity prefab with its Figma source node and applies the differences. It handles structural changes (added/removed children) and property changes (text content, colors, sizes, fonts, layout settings). Sprites are not modified — only properties and structure.

When to use

The designer made changes in Figma and the developer needs to bring the Unity prefab in sync. Rather than rebuilding from scratch (which would lose any manual Unity-side tweaks), this skill applies only the delta.

Input

The user needs to provide:

Prefab path — Unity asset path (e.g. Assets/UI/Prefabs/MyScreen.prefab)
Figma file key — the key from the Figma URL
Node ID — the Figma node this prefab was built from

If the user doesn't know the node ID, they may need to look it up in Figma. If the prefab was built with /build-prefab, the node ID might be discoverable from the component map via unity_list_assets with kind: "prefab".

Workflow

Step 1 — Fetch both sides

Do these in parallel:

figma_get_node(fileKey, nodeId) — download the current Figma tree
unity_get_hierarchy(prefabPath) — get the current Unity prefab hierarchy

Then call figma_get_node_names(fileKey, nodeId). It reads the copy figma_get_node saved, so it fails if run before or alongside it.

Step 2 — Compare

Walk both trees and identify differences:

Structural changes:

Nodes present in Figma but missing in Unity → need to be created
Nodes present in Unity but missing in Figma → candidates for removal (ask the user before deleting — they might be intentional Unity-side additions)

Property changes per node (compare by matching node names/paths):

Text: content, font size, font family, font style, color, alignment
RectTransform: size, position, anchors, pivot
Image: color, sprite path, image type
Layout: layout mode, spacing, padding, alignment
ContentSizeFitter: horizontal/vertical fit modes
Active state: enabled/disabled

Read the full file on GitHub · 163 lines

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.

24d ago Changed · +3 lines c9c7a4e4c2ee
1mo ago Changed 32c8a233aff7
1mo ago Changed · +7 lines e477baca4f52
2mo ago First seen · 153 lines · 110 tokens per session scan A 58ac68434398

Subscribe to this mod's changes

update-prefab is a skill published in the GitHub repository chav0/UnityFigmaMCP (11 stars, last pushed 25d ago), licensed MIT. It adds 110 tokens to every session and 1,478 once invoked, about $0.0004 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 2026-08-31.

Design and UX Game development ai ai-agents dotnet figma figma-to-code mcp

update-prefab next to 6 skills from other repositories
Mod	Type	Stars	Last push	Licence	Scan	Tokens	Works with
update-prefabchav0/UnityFigmaMCP	Skill	11	25d ago	MIT	A	110	Claude Code
figma-codegenawdr74100/figwright	Skill	1.3k	yesterday	MIT	A	145	Claude Code, Codex
figma-buildawdr74100/figwright	Skill	1.3k	yesterday	MIT	A	180	Claude Code, Codex
biome-creationmoorestech/moorestech	Skill	85	today	Apache-2.0	A	170	Claude Code
before-after-auditmoorestech/moorestech	Skill	85	today	Apache-2.0	A	81	Claude Code
vibefigmavibeflowing-inc/vibe_figma	Skill	849	28d ago	AGPL-3.0	A	77	Claude Code, Codex
design-pipelinesodam-ai/SoDam-Design-Kit	Skill	7	4d ago	Apache-2.0	A	77	Claude Code

UnityFigmaMCP: Skill for Claude Code