A tool for saving solved, non-trivial problems as searchable documentation. It gathers the cause, investigation, fix, and prevention details into a consistent solution file.

Use it after fixing an Elixir or Phoenix bug, resolving a difficult investigation, or completing a review that uncovered a useful solution.

It turns one debugging session into knowledge the team can reuse instead of losing the answer in chat history or memory.

compound — Skill for Claude Code by oliver-kriska

Install

Getting it into your agent

This one installs as part of its plugin. Adding the marketplace and installing the plugin brings it with everything else the plugin ships.

Claude Code

/plugin marketplace add oliver-kriska/claude-elixir-phoenix

Claude Code

/plugin install phx

Made for: Claude Code.

Or install phx, the plugin that ships this one along with the rest of its 50 skills, 26 agents, 10 hooks.

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.

README.md

[![agentmods](https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/compound.svg)](https://agentmods.dev/skills/oliver-kriska/claude-elixir-phoenix/compound)

Your own site

<a href="https://agentmods.dev/skills/oliver-kriska/claude-elixir-phoenix/compound"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/compound.svg" alt="Measured on agentmods" height="20"></a>

Per session 36 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.

When invoked 941 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.

Model	Per session	Once invoked
Fable 5.1	$0.00036	$0.00941
Opus 5	$0.00018	$0.00470
Sonnet 5	$0.00007	$0.00188
Haiku 4.5	$0.00004	$0.00094

Measured 4d ago against content hash 9c047e6f584d, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-08, from the pricing page.

Security

Grade A, and why

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 4d 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.

Origin

Copies of this mod

1 near-identical copy found in the catalogue:

phx-compound — 88% identical, 33 lines differ

plugins/elixir-phoenix/skills/compound/SKILL.md · 111 lines

How it starts

The opening of the file, as written. The whole thing — 111 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

/phx:compound Fixed N+1 query in user listing
/phx:compound Resolved LiveView timeout in dashboard
/phx: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

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

Only document non-trivial problems that required investigation.

Step 2: Search Existing Solutions

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

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.

Validate frontmatter against ${CLAUDE_PLUGIN_ROOT}/skills/compound-docs/references/schema.md, then create file using ${CLAUDE_PLUGIN_ROOT}/skills/compound-docs/references/resolution-template.md.

Write-blocked fallback: if writing to .claude/solutions/ is denied by permissions, do NOT silently drop the solution. Output the full solution doc inline (fenced markdown the user can paste), then suggest /phx:permissions to allow .claude/solutions/ writes for next time.

Step 4: Decision Menu

Continue (default)
Promote to Iron Law check — Add to iron-law-judge
Update skill reference — Add to relevant skill
Update CLAUDE.md — Add prevention rule

Auto-Trigger Phrases

When user says "that worked", "it's fixed", "problem solved", "the fix was" — suggest /phx:compound.

Read the full file on GitHub · 111 lines

Files

What ships with it

1 file 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.

references/compound-workflow.md 3.3 KB

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.

4d ago First seen · 111 lines · 36 tokens per session scan A 9c047e6f584d

Subscribe to this mod's changes

compound is a skill published in the GitHub repository oliver-kriska/claude-elixir-phoenix (539 stars, last pushed 2d ago), licensed MIT. It adds 36 tokens to every session and 941 once invoked, about $0.0002 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 2026-09-03.

Claude Code Memory and context Writing and docs automation claude claude-code-plugin claude-code-skills claude-skills

import

Import a self-contained NeatContext context bundle shared by another person, or reconcile a newer copy of a context already on this machine, leaving the source bundle unchanged. Use only when the user explicitly invokes this skill or asks to import a NeatContext bundle.

XTSoftwareLabs/neatcontext-plugins · 54 tokens

save

Save durable decisions, findings, plans, and implementation knowledge from the visible Codex conversation into a new or existing NeatContext context. Use only when the user explicitly invokes this skill or asks to preserve the current conversation as reusable context.

XTSoftwareLabs/neatcontext-plugins · 49 tokens

compound