elixir-phoenix-compound

elixir-phoenix-compound is a skill for Claude Code, Codex from ccarvalho-eng/codex-elixir-phoenix. It costs 19 tokens per session (668 once invoked), scanned A, original, MIT.

A tool for recording a difficult Phoenix problem and its solution as searchable project documentation. Phoenix is a web framework for Elixir.

In plain words
What is it for?
Use it after solving a non-trivial problem that required investigation. It searches existing solution notes and can create a new document, update a related one, or skip documentation when the problem is not substantial.
Why use it?
It prevents useful investigation work from being lost after a bug is fixed. Future developers can find the cause and resolution instead of repeating the same debugging process.

Skill for Claude CodeCodex

Written for Claude Code and Codex: $ARGUMENTS substitution, but also agents/openai.yaml present. Also seen: mentions AGENTS.md; mentions Codex.

Good fit Use it after solving a non-trivial problem that required investigation. It searches existing solution notes and can create a new document, update a related one, or skip documentation when the problem is not substantial.

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Install with agentmods
npx agentmods add skills/ccarvalho-eng/codex-elixir-phoenix/elixir-phoenix-compound
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 ccarvalho-eng/codex-elixir-phoenix --skill elixir-phoenix-compound
Clone the repo
git clone --depth 1 https://github.com/ccarvalho-eng/codex-elixir-phoenix

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 elixir-phoenix-compound

README.md
[![agentmods](https://agentmods.dev/badge/skills/ccarvalho-eng/codex-elixir-phoenix/elixir-phoenix-compound/github.svg)](https://agentmods.dev/skills/ccarvalho-eng/codex-elixir-phoenix/elixir-phoenix-compound)
Your own site
<a href="https://agentmods.dev/skills/ccarvalho-eng/codex-elixir-phoenix/elixir-phoenix-compound"><img src="https://agentmods.dev/badge/skills/ccarvalho-eng/codex-elixir-phoenix/elixir-phoenix-compound/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 elixir-phoenix-compound

Your own site · 80×15
<a href="https://agentmods.dev/skills/ccarvalho-eng/codex-elixir-phoenix/elixir-phoenix-compound"><img src="https://agentmods.dev/badge/skills/ccarvalho-eng/codex-elixir-phoenix/elixir-phoenix-compound.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 19 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 668 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 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 5.1 $0.00019 $0.00668
Opus 5.5 $0.00008 $0.00267
Sonnet 5.5 $0.00004 $0.00134
Haiku 4.5 $0.00002 $0.00067

Measured 1mo ago against content hash 34f16b936efb, method: parsed. Prices are Anthropic first-party input rates as of 2026-10-07, from the pricing page.

Security

Grade A, and why

elixir-phoenix-compound 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 1mo 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.

skills/elixir-phoenix-compound/SKILL.md · 87 lines

How it starts

The opening of the file, as written. The whole thing — 87 lines — stays where its author put it; the contents beside it link to each section on GitHub.

Compound — Capture Solutions as Knowledge

After fixing a problem, capture the solution as searchable institutional documentation.

Usage

`elixir-phoenix-compound` Fixed N+1 query in user listing
`elixir-phoenix-compound` Resolved LiveView timeout in dashboard
`elixir-phoenix-compound`   # Auto-detects from recent session context

Philosophy

Each unit of engineering work should make subsequent units easier — not harder.

Workflow

Step 1: Detect Context

  1. If $ARGUMENTS provided, use as description
  2. If no args, check scratchpad DEAD-END/DECISION entries, git diff, .codex/plans/{slug}/progress.md for recent completions
  3. If unclear, ask: "What problem did you just solve?"

Only document non-trivial problems that required investigation.

Step 2: Search Existing Solutions

Create .codex/solutions/ directory if it doesn't exist (run mkdir -p .codex/solutions). Then search .codex/solutions/ for relevant keywords using rg.

If found: Create new (different root cause), Update existing (same root cause, new symptom), or Skip.

Step 3: Gather Details and Create Solution

Extract from session context: module, symptoms, investigation steps, root cause, solution code, and prevention advice.

Open elixir-phoenix-compound-docs and use its schema and resolution template references before writing the solution file.

Step 4: Decision Menu

  1. Continue (default)
  2. Promote to Iron Law check — Add to iron-law-judge
  3. Update skill reference — Add to relevant skill
  4. Update AGENTS.md — Add prevention rule

Auto-Trigger Phrases

When user says "that worked", "it's fixed", "problem solved", "the fix was" — suggest elixir-phoenix-compound.

Iron Laws

  1. YAML frontmatter validates or STOP
  2. Symptoms must be specific — not "it broke"
  3. Root cause is WHY, not WHAT
  4. One problem per file
  5. NEVER document a fix before verifying it works — run mix compile && mix test first; unverified solutions poison the knowledge base

Read the full file on GitHub · 87 lines

Files

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.

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. 1mo ago First seen · 87 lines · 19 tokens per session scan A 34f16b936efb

Subscribe to this mod's changes

elixir-phoenix-compound is a skill published in the GitHub repository ccarvalho-eng/codex-elixir-phoenix (11 stars, last pushed 5mo ago), licensed MIT. It adds 19 tokens to every session and 668 once invoked, about $0.0001 per session on Opus 5.5. 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.