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 oliver-kriska/claude-elixir-phoenix --skill learn-from-fixgit clone --depth 1 https://github.com/oliver-kriska/claude-elixir-phoenixWrote 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/oliver-kriska/claude-elixir-phoenix/learn-from-fix)<a href="https://agentmods.dev/skills/oliver-kriska/claude-elixir-phoenix/learn-from-fix"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/learn-from-fix/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/oliver-kriska/claude-elixir-phoenix/learn-from-fix"><img src="https://agentmods.dev/badge/skills/oliver-kriska/claude-elixir-phoenix/learn-from-fix.svg" alt="Reviewed on agentmods" width="80" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 1 finding, up to high
These are SkillSpector’s own severities. On a checked sample its high-severity flags on skills were ~96% false positives — a documented command, a public API, a “never do X” rule — so we show them as a caution to read, not a verdict. Why →
- high Agent Snooping · line 55 Skill reads from agent configuration directories (.claude/, .codex/, .gemini/). These directories may contain API keys, personal settings, and other credentials that the skill has no legitimate need to access.Fix: Remove all code or instructions that access agent configuration directories (.claude/, .codex/, .gemini/). If configuration values are needed, pass them explicitly as parameters or environment variabl
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 | $0.00046 | $0.01649 |
| Opus 5 | $0.00023 | $0.00825 |
| Sonnet 5 | $0.00009 | $0.00330 |
| Haiku 4.5 | $0.00005 | $0.00165 |
Grade A, and why
learn-from-fix 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 6d 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.
Copies of this mod
1 near-identical copy found in the catalogue:
- phx-learn-from-fix — 94% identical, 26 lines differ
How it starts
The opening of the file, as written. The whole thing — 180 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Learn From Fix
After fixing a bug or receiving a correction, capture the lesson to prevent future mistakes.
Usage
/phx:learn-from-fix Fixed N+1 query in user listing - was missing preload
/phx:learn-from-fix String vs atom key mismatch in params handling
/phx:learn-from-fix LiveView assign_async needs render_async in tests
/phx:learn-from-fix --library ical --scope personal ICal.to_ics output needs CRLF line endings
/phx:learn-from-fix --library ical --scope project Use method: "PUBLISH" for calendar feeds
Workflow
Step 1: Verify the Lesson
Persist only one of:
- A completed fix verified by tests, reproduction, or user confirmation
- An explicit rule the user taught or asked to save
Stop without writing if neither condition is met.
Do not save a hypothesis, unverified workaround, investigation narrative, or
unsolved error. Use /phx:compound for a detailed completed investigation.
Capture the root cause as a concise actionable rule, not the symptom.
Step 2: Select the Route
When both --library <package> and --scope personal|project are present,
use the Library Route. Require both flags; do not guess scope.
For the skill directory only, trim surrounding whitespace and lowercase the
package name. Preserve underscores when forming directory names
(phoenix_live_view becomes hex-phoenix_live_view).
Validate the normalized name against ^[a-z][a-z0-9_]+$. If it does not match,
ask for a valid Hex package identifier instead of replacing characters or
inventing a name. Use the trimmed original identifier, not the normalized
directory name, to look up mix.lock.
Without --library, use the General Correction Route.
Step 3: Check Existing Knowledge
Check if already documented:
- Grep project CLAUDE.md and
~/.claude/CLAUDE.mdfor the pattern keyword - Check auto-memory files for similar lessons
- For library lessons, inspect both
~/.claude/skills/hex-<package>/SKILL.mdand.claude/skills/hex-<package>/SKILL.md - Read
${CLAUDE_SKILL_DIR}/references/common-mistakes.md(READ-ONLY plugin reference — do NOT edit this file)
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.
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.
- 6d ago First seen · 180 lines · 46 tokens per session scan A 3b6e5f6982b4
learn-from-fix is a skill published in the GitHub repository oliver-kriska/claude-elixir-phoenix (542 stars, last pushed 4d ago), licensed MIT. It adds 46 tokens to every session and 1,649 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.
Other skills, from other repositories
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.
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.
create
Create a fresh NeatContext context from a user-defined behavioral profile and an existing local knowledge folder. Use only when the user explicitly invokes this skill or asks to create a new context rather than save the current conversation.
export
Export a NeatContext context saved from a conversation into a self-contained bundle folder that can be shared or moved to another machine. Use only when the user explicitly invokes this skill or asks to export a NeatContext context.
use
Connect or switch Codex to a local NeatContext Context by name or list number. Use only when the user explicitly invokes this skill, names a context to connect, or agrees to a routing suggestion.
delete
Preview and permanently delete a NeatContext context while preserving any externally linked knowledge folder. Use only when the user explicitly invokes this skill or clearly asks to delete a context.