everything-react-native-expo: Skill for Claude Code

.claude/skills/erne-feature/SKILL.md

erne-feature is a skill for Claude Code from JubaKitiashvili/everything-react-native-expo. It costs 16 tokens per session (352 once invoked), scanned A, original, MIT.

A focused workflow for implementing one clearly bounded part of a React Native app, such as a screen, custom hook, API module, or reusable component.

In plain words
What is it for?
It is for building an isolated feature unit with loading, error, empty, and success states, plus checks for missing data, network failures, and platform differences.
Why use it?
It keeps small deliverables easier to review and integrate, while requiring explicit types and handling for common failure cases.

Skill for Claude Code

Written for Claude Code: installed under .claude/.

This is JubaKitiashvili/everything-react-native-expo's own configuration. It tells Claude Code how to work on everything-react-native-expo itself, so it is not a mod to install elsewhere. Copy it as a starting point and replace the rules that are about this project. Everything everything-react-native-expo configures →

Part of the erne-universal plugin — 45 skills, 12 agents shipped together

Reuse

Borrowing it

Nothing to install: this file belongs to JubaKitiashvili/everything-react-native-expo. Take a copy, put it at the same path in your own repository, and replace the rules that are about this project with yours.

Copy the file
curl -O https://raw.githubusercontent.com/JubaKitiashvili/everything-react-native-expo/main/.claude/skills/erne-feature/SKILL.md
Clone the repo
git clone --depth 1 https://github.com/JubaKitiashvili/everything-react-native-expo

Made for: Claude Code.

Or install erne-universal, the plugin that ships this one along with the rest of its 45 skills, 12 agents.

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 erne-feature

README.md
[![agentmods](https://agentmods.dev/badge/skills/jubakitiashvili/everything-react-native-expo/erne-feature/github.svg)](https://agentmods.dev/skills/jubakitiashvili/everything-react-native-expo/erne-feature)
Your own site
<a href="https://agentmods.dev/skills/jubakitiashvili/everything-react-native-expo/erne-feature"><img src="https://agentmods.dev/badge/skills/jubakitiashvili/everything-react-native-expo/erne-feature/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 erne-feature

Your own site · 80×15
<a href="https://agentmods.dev/skills/jubakitiashvili/everything-react-native-expo/erne-feature"><img src="https://agentmods.dev/badge/skills/jubakitiashvili/everything-react-native-expo/erne-feature.svg" alt="Reviewed on agentmods" width="80" height="20"></a>
Per session 16 Skills are progressive disclosure: only the name and description are preloaded; the body loads when the skill is used.
When invoked 352 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 $0.00016 $0.00352
Opus 5 $0.00008 $0.00176
Sonnet 5 $0.00003 $0.00070
Haiku 4.5 $0.00002 $0.00035

Measured 11d ago against content hash edccfc86683c, method: parsed. Prices are Anthropic first-party input rates as of 2026-09-11, from the pricing page.

Security

Grade A, and why

erne-feature 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 11d 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:

  • feature — 88% identical, 16 lines differ
.claude/skills/erne-feature/SKILL.md · 38 lines

What it actually says

/erne-feature — Focused Feature Unit

You are executing the /erne-feature command. Use the feature-builder agent to implement a discrete, scoped feature unit.

Process

  1. Scope the unit — Identify exactly one deliverable: a single screen, a custom hook, an API module, or a reusable component
  2. Check dependencies — Verify types, API contracts, and shared state are defined before starting
  3. Implement — Using the feature-builder agent's process:
    • Write the code with all states handled (loading, error, empty, success)
    • Type everything explicitly (return types, param interfaces, no any)
    • Handle edges (null checks, empty arrays, network failures, platform differences)
  4. Deliver — Complete file with props/params interface, dependencies list, and integration point

When to Use

  • Building a single screen, hook, or component in isolation
  • Working in parallel with another agent on a larger feature
  • Quick, scoped implementation tasks with clear boundaries

Parallel Work

When used alongside /erne-code (senior-developer):

  • /erne-code handles: data layer, stores, navigation skeleton, complex multi-screen flows
  • /erne-feature handles: individual screens, isolated components, utility hooks, API wrappers
  • Coordinate via shared type definitions and agreed interfaces

Notes

  • Reference the active platform rules layer for conventions
  • Keep scope tight — if the task touches more than 3 files, use /erne-code instead
  • Every delivered unit must include its integration point documentation
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. 11d ago First seen · 38 lines · 16 tokens per session scan A edccfc86683c

Subscribe to this mod's changes

erne-feature is a skill published in the GitHub repository JubaKitiashvili/everything-react-native-expo (45 stars, last pushed 5mo ago), licensed MIT. It adds 16 tokens to every session and 352 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 2026-08-30.

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