Rn Device QA

RN Device QA

Overview

This skill plans the smallest runtime evidence surface that can prove the requested acceptance criterion. It keeps static screenshots, JavaScript logs, interactive automation, and external state changes distinct. It does not operate a device, install tools, launch apps, or change external state.

When to Use

• "verify this React Native screen on a device"
• "run acceptance checks on the simulator or emulator"
• "collect runtime evidence for this mobile flow"
• "explore this app and record reproducible QA findings"

Prerequisites

• Identify the requested app build and a read-only fingerprint source. Record the target platform, device or simulator identity, app identifier, account class, and starting state. Report build attribution as [UNCERTAIN] when no fingerprint source exists. Use an Android serial, iOS UDID, or one booted simulator identity when the evidence helper supports it.
• For simulator capture, require exactly one booted simulator overall. Confirm that the booted simulator matches the recorded identity.
• A Metro target descriptor carries no hardware identifier: it reports a title, a device name, and an app identifier only. Screenshot evidence is pinned by serial or UDID, so combining the two surfaces requires a read-only mapping from the recorded serial or UDID to the selected Metro target. Establish that mapping by confirming exactly one connected device or booted simulator reports the recorded device name, using adb devices -l for Android or xcrun simctl list devices booted for a simulator. Report device attribution as [UNCERTAIN] when two targets share a device name and app identifier, and do not present the screenshot and the log as evidence about the same device.
• Record METRO_HOST as the selected Metro host:port before inspecting targets or collecting logs.
• Record APP_ID as the expected app identifier for Metro preflight and collection descriptor verification.
• Record METRO_SELECTOR as a unique device name or other unique target selector for Metro preflight and collection.
• Set METRO_SKILL_DIR to the absolute base directory of the active rn-metro-console skill.
• Confirm the requested evidence can be produced without changing external state, or identify the required separate authorization.
• Identify a disposable fixture before a flow creates, edits, or deletes records.

Quick Steps

1. Map each acceptance criterion to a target identity, build-attribution status, and evidence surface before any device operation.
2. Route rendered-screen evidence to rn-device-capture with the selected Android serial or iOS UDID when supported.
   • For a simulator, first inspect xcrun simctl list devices booted and require exactly one booted simulator overall. Confirm that it matches the recorded identity.
   • When the helper cannot select an ambiguous target, report [TOOL_FAILED] instead of attributing automatic output to the acceptance run.
3. Route bounded JavaScript console.* evidence to rn-metro-console.
   • Run node "$METRO_SKILL_DIR/rn-console.mjs" --host "$METRO_HOST" --device "$METRO_SELECTOR" --preflight before collecting logs.
   • Confirm that its JSON descriptor identifies the recorded device and app identifier.
   • Report [TOOL_FAILED] when preflight cannot select one eligible React Native target.
   • Report device attribution as [UNCERTAIN] when the recorded serial or UDID cannot be mapped to that target, even when preflight selects exactly one.
4. When the criterion needs interaction, a UI tree, native logs, network output, recording, replay, or an external state change, report the required evidence surface and separate authorization in a handoff.
5. For a JavaScript log that comes from an interaction, state this handoff:
   • Record the target platform, device name, app identifier, serial or UDID when applicable, and build fingerprint source.
   • Use --host "$METRO_HOST" --device "$METRO_SELECTOR" for every collection. Confirm that [rn-console] ready identifies the recorded device and app identifier before reading the output.
   • Start node "$METRO_SKILL_DIR/rn-console.mjs" --host "$METRO_HOST" --device "$METRO_SELECTOR" in a background session with a bounded duration.
   • Wait for its [rn-console] ready status.
   • Have an authorized device operator trigger the path while the collector is active.
   • Wait for the collector to return before reading its output.
6. Record the starting state, observed result, evidence path, build-attribution status, and untested criteria.

Evidence Selection

How It Works

acceptance criterion
  -> device and fixture state
  -> smallest valid evidence surface
  -> separate authorization handoff when required
  -> artifact review
  -> verified, partial, or untested report

Safety and Verification

Start with read-only discovery when it can identify the target state. Require explicit user authorization before a handoff installs, uninstalls, launches, terminates, uses interactive automation, changes an external record, sends data, makes a purchase, publishes, or uses a production account. The authorization must name the target build, device or simulator, account class, and disposable fixture when state can change. Do not use an implicit installer to obtain an automation tool. This reader does not:

• Install or uninstall an app.
• Launch an app.
• Use interactive automation.
• Change external state.

Report [TOOL_FAILED] when required interactive automation is unavailable. Report [PARTIAL] when the available screenshot or log cannot prove the requested criterion. Report build attribution as [UNCERTAIN] when no read-only fingerprint ties the evidence to the requested build. Do not report command round-trip time or placeholder values as startup, frame, FPS, CPU, or memory measurements.

Common Mistakes

Reference

• rn-device-capture
• rn-metro-console

If you need reusable device QA coverage across projects, open a Discussion in the RN Agents Kit repository.