uloop-hot-reload

A Unity development skill that applies many C# code changes directly to the running Editor without restarting or recompiling the whole project. New types and some cross-file changes still require a normal compile.

In plain words
What is it for?
Use it to hot-reload changed C# files, add compatible methods or fields, revert hot-reloaded changes, and identify edits that could not be patched.
Why use it?
It shortens the wait when testing edits to existing methods, so developers can iterate while Unity is in Edit Mode or Play Mode.

Skill for Claude CodeCodex

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.

agentmods
npx agentmods add skills/hatayama/unity-cli-loop/uloop-hot-reload
Any agent
npx skills add hatayama/unity-cli-loop --skill uloop-hot-reload
Clone the repo
git clone --depth 1 https://github.com/hatayama/unity-cli-loop

Made for: Claude Code, Codex.

Per session 66 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 1,384 The whole file, excluding the scripts and references it only reads on demand.
Security scan A 0 findings. Scan, not verified.
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 $0.00066 $0.01384
Opus 5 $0.00033 $0.00692
Sonnet 5 $0.00013 $0.00277
Haiku 4.5 $0.00007 $0.00138

Measured 2d ago against content hash 8af1a0457013, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

uloop-hot-reload 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 2d 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.

.agents/skills/uloop-hot-reload/SKILL.md · 104 lines

How it starts

The opening of the file, as written. The whole thing — 104 lines — stays where its author put it; the contents beside it link to each section on GitHub.

uloop hot-reload

Replaces method bodies in the running Editor (EditMode or PlayMode) directly from edited project source files — no domain reload, no attributes, no source markers. Private/internal member access, static methods, return values, async methods, and iterators all work within the limits below — including private access inside async, iterator, lambda, local-function, and LINQ-query bodies. Methods that cannot be patched are reported per method as Skipped or Failed; one unpatchable method never aborts the rest of the run.

Usage

uloop hot-reload --files Assets/Scripts/Enemy.cs
uloop hot-reload --files Assets/Scripts/Enemy.cs,Assets/Scripts/Boss.cs
uloop hot-reload
uloop hot-reload --revert-all

Multiple files are passed as one comma-separated value (or a JSON array); array options consume exactly one value token.

A brand-new script — or any script under a brand-new .asmdef — cannot be hot-reloaded before its first import: Unity has not compiled it into any assembly yet. Run uloop compile once to import new files, then iterate on them with hot reload.

Parameters

Parameter Type Default Description
--files array - Project-relative .cs paths whose method bodies should be hot-reloaded. When omitted or empty on apply, selects the .cs sources whose bytes changed since the last compile snapshot, capped at 50 changed files per assembly with a warning when the cap trims the list; run uloop compile first when no snapshot exists, or pass explicit paths when no changed source is found
--revert-all flag - Remove every active hot-reload patch and clear the patch ledger. When set, --files is ignored
--status flag - Lists the currently active changes (patched methods and added members) without applying or reverting anything.

When --files is omitted or empty, a source is selected only when its compilation assembly has a snapshot directory and that source has its own snapshot file. A missing per-file snapshot is left out rather than guessed as changed, so pass the file explicitly or run uloop compile to establish a complete baseline.

Read the full file on GitHub · 104 lines

Files

What ships with it

5 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. 2d ago First seen · 104 lines · 66 tokens per session scan A 8af1a0457013

Subscribe to this mod's changes

uloop-hot-reload is a skill published in the GitHub repository hatayama/unity-cli-loop (522 stars, last pushed 2d ago), licensed MIT. It adds 66 tokens to every session and 1,384 once invoked, about $0.0003 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 2026-08-31.

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