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 ericrisco/rsc-harness --skill expogit clone --depth 1 https://github.com/ericrisco/rsc-harnessWrote 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/ericrisco/rsc-harness/expo)<a href="https://agentmods.dev/skills/ericrisco/rsc-harness/expo"><img src="https://agentmods.dev/badge/skills/ericrisco/rsc-harness/expo.svg" alt="Measured on agentmods" height="20"></a>- NVIDIA SkillSpector warn
SkillSpector: 11 findings, up to medium
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 →
- medium MCP Rug Pull · line 52 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 123 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 166 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium MCP Rug Pull · line 168 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
- medium Rogue Agent · line 125 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium Rogue Agent · line 129 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium Rogue Agent · line 132 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium Rogue Agent · line 226 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium Rogue Agent · line 128 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium Rogue Agent · line 226 Skill establishes unauthorized persistence across sessions via cron jobs, startup scripts, or state files. Session persistence allows an attacker to maintain access beyond the current interaction.Fix: Remove any persistence mechanisms (cron jobs, startup scripts, state files). Skills should not maintain state across sessions without explicit user consent.
- medium MCP Rug Pull · line 167 npx commands without a version suffix (e.g. @1.0.0) create a rug-pull risk if the upstream server is compromised and publishes a malicious update.Fix: Pin the version: npx @scope/[email protected]
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 | $0.00079 | $0.02964 |
| Opus 5 | $0.00039 | $0.01482 |
| Sonnet 5 | $0.00016 | $0.00593 |
| Haiku 4.5 | $0.00008 | $0.00296 |
Grade A, and why
expo 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.
How it starts
The opening of the file, as written. The whole thing — 245 lines — stays where its author put it; the contents beside it link to each section on GitHub.
Expo & EAS: shipping React Native
Hand-off — the app vs its motion. This skill owns the Expo platform: router, config plugins, EAS,
native modules, store builds. Animation and gestures — Reanimated worklets, the UI runtime,
sheets, screen transitions, press feedback, haptics, motion that stutters on a real device — are
../motion-craft/SKILL.md's.
What this skill owns
Expo is the toolchain and EAS cloud platform layered on React Native: cloud builds, store submission, over-the-air JS updates, and native configuration declared in JavaScript instead of hand-edited Xcode/Gradle projects. This skill owns the shipping pipeline and native-config-via-JS.
The verb rule of thumb: if the verb is build / submit / update / prebuild /
plugin / EAS / channel / runtime-version, you are in expo. If it is render /
navigate / animate / bridge / write a native module, route to react-native.
Other exits: web React/hooks/state → react, a Dart app → flutter, native-only
Swift/Kotlin → swift-ios/kotlin-android, a desktop wrapper → tauri/electron,
CI unrelated to EAS → github-actions.
Current stable as of 2026-06-02: Expo SDK 55 — React Native 0.83.1, React 19.2.0, shipped 2026-02-25. SDK 56 is in beta (beta opened 2026-05-06, ~2-week window; RN 0.85.2, React 19.2.3) — upcoming, not yet shipped stable. Both run exclusively on the New Architecture; the Legacy Architecture was removed in SDK 55.
Decision rules
| Situation | Do this | Why / not that |
|---|---|---|
| New app, want config-as-JS | managed + prebuild (CNG) — no committed ios//android/ |
native dirs are regenerable artifacts; hand-edits get blown away |
| You truly need to hand-edit native code long-term | bare (commit ios//android/) |
last resort; you lose prebuild --clean upgrades |
| Quick demo, only Expo-SDK modules | Expo Go | zero build, but custom native deps will crash |
| Any custom native dependency or plugin | dev build (developmentClient: true) |
Expo Go cannot load arbitrary native code |
| Runtime version, picking a policy | fingerprint (auto-bumps on native change) |
safest default; prevents serving JS to an incompatible binary |
| Runtime tied to your release version | appVersion |
simpler, but you must remember to bump it on native changes |
What ships with it
5 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.
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 · 245 lines · 79 tokens per session scan A a84ec630b11a
expo is a skill published in the GitHub repository ericrisco/rsc-harness (70 stars, last pushed yesterday), licensed MIT. It adds 79 tokens to every session and 2,964 once invoked, about $0.0004 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.
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Uniwind — Tailwind CSS v4 styling for React Native. Use when adding, building, or debugging components in a React Native project that uses Uniwind classNames. Covers setup, Metro config, global.css, theming, className props, accent- color props, platform/data/state/responsive variants, CSS variables, custom utilities…
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Incrementally upgrade React Native Storybook across the supported migration paths. Use when upgrading @storybook/react-native projects from 5.3.x to 6.5.x, 6.5.x to 7.6.x, 7.6.x to 8.3.x, 8.x to 9.x, or 9.x to 10.x. Detect the currently installed Storybook version, choose only the next migration step, update…
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Orchestrate headless Android debugging via JDWP. ACTIVATE this skill whenever asked to debug an Android application, set line or exception breakpoints, inspect runtime variables or Jetpack Compose state, step through execution, evaluate live expressions, watch fields, or diagnose runtime crashes.