invariant-hunter-go

invariant-hunter-go is a skill for Claude Code from skyosev/agent-skills. It costs 73 tokens per session (5,163 once invoked), scanned A, original, no licence file.

A Go code-review skill that checks whether code protects its basic assumptions, called invariants. It looks for risks such as unchecked errors, nil pointers, ignored cancellation, unsafe type conversions, invalid zero values, and missing input checks.

In plain words
What is it for?
Use it to tighten Go domain models, check constructors and validation boundaries, improve error handling, and reduce panic risks.
Why use it?
It helps find cases where invalid data or unexpected states could cause crashes, hidden failures, or incorrect behavior.

Skill for Claude Code

Written for Claude Code: disable-model-invocation in frontmatter.

Good fit Use it to tighten Go domain models, check constructors and validation boundaries, improve error handling, and reduce panic risks.

Compare 6 skills from other repositories ↓
Install with agentmods
npx agentmods add skills/skyosev/agent-skills/invariant-hunter-go
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 skyosev/agent-skills --skill invariant-hunter-go
Clone the repo
git clone --depth 1 https://github.com/skyosev/agent-skills

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.

agentmods badge for invariant-hunter-go

README.md
[![agentmods](https://agentmods.dev/badge/skills/skyosev/agent-skills/invariant-hunter-go/github.svg)](https://agentmods.dev/skills/skyosev/agent-skills/invariant-hunter-go)
Your own site
<a href="https://agentmods.dev/skills/skyosev/agent-skills/invariant-hunter-go"><img src="https://agentmods.dev/badge/skills/skyosev/agent-skills/invariant-hunter-go/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 invariant-hunter-go

Your own site · 80×15
<a href="https://agentmods.dev/skills/skyosev/agent-skills/invariant-hunter-go"><img src="https://agentmods.dev/badge/skills/skyosev/agent-skills/invariant-hunter-go.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 73 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 5,163 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 unknown 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 $0.00073 $0.05163
Opus 5 $0.00036 $0.02582
Sonnet 5 $0.00015 $0.01033
Haiku 4.5 $0.00007 $0.00516

Measured 11d ago against content hash 1345d9fe0de7, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

invariant-hunter-go 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 11d 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.

hunter-party-go/invariant-hunter-go/SKILL.md · 442 lines

The source is not reproduced here

No licence file

A repository with no LICENSE is all rights reserved by default, so the body is not copied here. The metadata, the measurements and the link are.

Read it on GitHub

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. 11d ago First seen · 442 lines · 73 tokens per session scan A 1345d9fe0de7

Subscribe to this mod's changes

invariant-hunter-go is a skill published in the GitHub repository skyosev/agent-skills (5 stars, last pushed today), with no licence file. It adds 73 tokens to every session and 5,163 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 2026-08-31.