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.
npx skills add rsturla/eternal-images --skill use-modern-gogit clone --depth 1 https://github.com/rsturla/eternal-imagesWrote 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.
[](https://agentmods.dev/skills/rsturla/eternal-images/use-modern-go)<a href="https://agentmods.dev/skills/rsturla/eternal-images/use-modern-go"><img src="https://agentmods.dev/badge/skills/rsturla/eternal-images/use-modern-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.
<a href="https://agentmods.dev/skills/rsturla/eternal-images/use-modern-go"><img src="https://agentmods.dev/badge/skills/rsturla/eternal-images/use-modern-go.svg" alt="Reviewed on agentmods" width="80" height="20"></a>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 | $0.00032 | $0.00535 |
| Opus 5 | $0.00016 | $0.00267 |
| Sonnet 5 | $0.00006 | $0.00107 |
| Haiku 4.5 | $0.00003 | $0.00053 |
Grade A, and why
use-modern-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 12d 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.
This is a copy
94% identical to use-modern-go — 7 lines differ, which has more behind it and is treated as the original. This page carries a canonical link to it rather than competing with it.
What it actually says
Modern Go Guidelines CLI
Always write modern, idiomatic Go code. Use the Modern Go Guidelines CLI as the source of truth for modern Go idioms that may be newer than your knowledge cutoff.
Run: sh "<skill-dir>/scripts/run-tool.sh"
First run and approvals:
On first use, the wrapper installs the Modern Go Guidelines CLI in a local cache directory.
Subcommands:
listexplain
Before editing Go code:
-
Call the wrapper's
listsubcommand for the relevant Go file.Prefer passing the file you are about to edit:
sh "<skill-dir>/scripts/run-tool.sh" list --file-path path/to/file.goThe CLI resolves the applicable Go version from go.mod, go.work, the local Go toolchain, or an explicit override.
-
If the target Go version is already known, you may pass it directly:
sh "<skill-dir>/scripts/run-tool.sh" list --go-version 1.24 -
Read the complete list output before deciding which guidelines apply.
The list output is ordered newest first. Read the full output because older supported guidelines may still apply.
Do not pipe the output through head, tail, grep, sed, or any other truncating/filtering command. Important guidelines may otherwise be missed.
-
Treat returned guidelines as authoritative for modern Go style choices in code you are editing.
If a guideline applies, follow it even when nearby code or repository convention uses an older pattern. Skip it only when it would not compile, would change behavior, or clearly does not match the edited code. Before skipping a returned guideline that seems relevant, call the wrapper's
explainsubcommand for that guideline ID.
Call explain only when a specific guideline may apply and you need the detailed explanation or examples. Request only the guideline IDs you intend to evaluate or apply:
sh "<skill-dir>/scripts/run-tool.sh" explain sync_waitgroup_go
Multiple guideline IDs may be requested as positional arguments:
sh "<skill-dir>/scripts/run-tool.sh" explain atomic_types errors_as_type
Do not call explain without guideline IDs. Use list first to discover the short guideline list for the target Go version, then call explain for the specific returned IDs that need more context.
What ships with it
2 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.
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.
- 12d ago First seen · 62 lines · 32 tokens per session scan A 16bd5c8d4c14
use-modern-go is a skill published in the GitHub repository rsturla/eternal-images (11 stars, last pushed yesterday), licensed MIT. It adds 32 tokens to every session and 535 once invoked, about $0.0002 per session on Opus 5. A static security scan graded it A with 0 findings. It is 94% identical to use-modern-go, differing in 7 lines, and is treated as a copy.
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