hello-world

hello-world is a skill for Claude Code, Codex from VictorTomaili/skill-cli. It costs 17 tokens per session (275 once invoked), scanned A, original, MIT.

A smallest-example skill that shows how to create a custom agent instruction triggered by commands such as /hello or /hi.

In plain words
What is it for?
Learning the skill format, defining triggers and instructions, and installing a local example.
Why use it?
It gives you a copy-paste starting point instead of requiring you to design a skill from scratch.

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/victortomaili/skill-cli/hello-world
Any agent
npx skills add VictorTomaili/skill-cli --skill hello-world
Clone the repo
git clone --depth 1 https://github.com/VictorTomaili/skill-cli

Made for: Claude Code, Codex.

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 hello-world

README.md
[![agentmods](https://agentmods.dev/badge/skills/victortomaili/skill-cli/hello-world.svg)](https://agentmods.dev/skills/victortomaili/skill-cli/hello-world)
Your own site
<a href="https://agentmods.dev/skills/victortomaili/skill-cli/hello-world"><img src="https://agentmods.dev/badge/skills/victortomaili/skill-cli/hello-world.svg" alt="Measured on agentmods" height="20"></a>
Per session 17 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 275 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 $0.00017 $0.00275
Opus 5 $0.00009 $0.00138
Sonnet 5 $0.00003 $0.00055
Haiku 4.5 $0.00002 $0.00028

Measured 3d ago against content hash 83dbf06bca3d, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

hello-world 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 3d 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.

examples/hello-world/SKILL.md · 44 lines

What it actually says

Hello, world!

This is the smallest possible skill. When a user types /hello (or /hi), the agent runs skill trigger hello and this body is loaded into context.

What to do

  1. Greet the user warmly.
  2. Briefly offer to help with whatever they're working on.

Make it your own

Replace the frontmatter and this body with your own instructions. The only required field is name; description, version, and triggers are recommended.

---
name: my-skill            # required, plain identifier (a-z 0-9 . _ -)
description: What it does # recommended — shown by `skill list` / `skill show`
version: 1.0.0            # recommended — surfaced by `skill update`
triggers: [x, y]          # optional — powers /x and /y
---

Try it locally

# from a checkout of this repo, install this example into your store:
skill install ./examples

# then:
skill list
skill trigger hello
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. 3d ago First seen · 44 lines · 17 tokens per session scan A 83dbf06bca3d

Subscribe to this mod's changes

hello-world is a skill published in the GitHub repository VictorTomaili/skill-cli (4 stars, last pushed 10d ago), licensed MIT. It adds 17 tokens to every session and 275 once invoked, about $0.0001 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.