using-elixir-skills

using-elixir-skills is a skill for Claude Code, Codex from georgeguimaraes/claude-code-elixir. It costs 96 tokens per session (549 once invoked), scanned A, original, Apache-2.0.

A routing guide for Elixir projects. Elixir is a programming language, while Phoenix, Ecto, and OTP are commonly used parts of its web, database, and concurrency ecosystem.

In plain words
What is it for?
Use it when working with .ex or .exs files, Mix projects, Phoenix, Ecto, OTP, LiveView, GenServer, supervisors, or background jobs.
Why use it?
It tells the agent which focused guidance to use before exploring or changing Elixir code. This helps avoid using the wrong approach for web, database, background-job, or concurrency work.

Skill for Claude CodeCodex

Part of the elixir plugin — 6 skills, 1 hook shipped together

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/georgeguimaraes/claude-code-elixir/using-elixir-skills
Any agent
npx skills add georgeguimaraes/claude-code-elixir --skill using-elixir-skills
Clone the repo
git clone --depth 1 https://github.com/georgeguimaraes/claude-code-elixir

Made for: Claude Code, Codex.

Or install elixir, the plugin that ships this one along with the rest of its 6 skills, 1 hook.

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 using-elixir-skills

README.md
[![agentmods](https://agentmods.dev/badge/skills/georgeguimaraes/claude-code-elixir/using-elixir-skills.svg)](https://agentmods.dev/skills/georgeguimaraes/claude-code-elixir/using-elixir-skills)
Your own site
<a href="https://agentmods.dev/skills/georgeguimaraes/claude-code-elixir/using-elixir-skills"><img src="https://agentmods.dev/badge/skills/georgeguimaraes/claude-code-elixir/using-elixir-skills.svg" alt="Measured on agentmods" height="20"></a>
Per session 96 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 549 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 $0.00096 $0.00549
Opus 5 $0.00048 $0.00275
Sonnet 5 $0.00019 $0.00110
Haiku 4.5 $0.00010 $0.00055

Measured 5d ago against content hash cafc4a266396, method: parsed. Prices are Anthropic first-party input rates as of 2026-08-30, from the pricing page.

Security

Grade A, and why

using-elixir-skills 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 5d 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.

plugins/elixir/skills/using-elixir-skills/SKILL.md · 44 lines

What it actually says

THIS IS NOT OPTIONAL. Skills tell you HOW to explore and WHAT to look for. You cannot rationalize your way out of this.

The Rule

Elixir/Phoenix/OTP task → Invoke skill FIRST → Then explore/research → Then write code

Skills come before exploration. The skills tell you what patterns to look for, what questions to ask, and what anti-patterns to avoid. Exploring without the skill means you don't know what you're looking for.

Skill Triggers

Trigger Phrases Skill to Invoke
code, implement, write, design, architecture, structure, pattern elixir-thinking
LiveView, Plug, PubSub, mount, channel, socket, component phoenix-thinking
context, schema, Ecto, changeset, preload, Repo, migration ecto-thinking
GenServer, supervisor, Task, ETS, bottleneck, Broadway otp-thinking
Oban, workflow, job queue, cascade, graft, background job, async job oban-thinking

Red Flags

These thoughts mean STOP—invoke the skill:

Thought Reality
"Let me explore the codebase first" Skills tell you WHAT to look for. Invoke first.
"Let me understand the code first" Skills guide understanding. Invoke first.
"But first, let me..." No. Skills come first. Always.
"I'll add a process to organize this" Processes are for runtime, not organization.
"GenServer is the Elixir way" GenServer is a bottleneck by design.
"I'll query in mount" mount is called twice.
"Task.async is simpler" Use Task.Supervisor in production.
"I know Elixir well enough" These skills contain paradigm shifts. Invoke them.
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. 5d ago First seen · 44 lines · 96 tokens per session scan A cafc4a266396

Subscribe to this mod's changes

using-elixir-skills is a skill published in the GitHub repository georgeguimaraes/claude-code-elixir (168 stars, last pushed 4mo ago), licensed Apache-2.0. It adds 96 tokens to every session and 549 once invoked, about $0.0005 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 2026-08-30.

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