revyl-cli-dev-loop

Revyl CLI Dev Loop Skill

Use this skill when the user wants the generic Revyl CLI dev loop instead of MCP tool-by-tool orchestration. Start from the app's real stack, keep the session running, and use the device as the source of truth.

Native Agent Behavior

• Ask at most 1-3 concise clarification questions only when the target app, platform, session, URL, or sensitive action cannot be inferred from the repo or Revyl CLI.
• Prefer safe defaults and keep moving when revyl init --detect, revyl dev list, revyl app list, screenshots, or reports can answer the question.
• When Revyl prints a viewer or local app URL, open it in the native browser/tool surface when available: Codex Browser/in-app browser for local URLs, Revyl viewer URLs, screenshots, and page checks; Claude Code .claude/skills slash-command discovery plus WebFetch/WebSearch or configured MCP/browser tools; Cursor .cursor/skills plus .cursor/rules/revyl-skills.mdc and available MCP/browser tools.
• If no browser tool is exposed, report the URL and verify through revyl device screenshot or revyl device report instead of claiming browser access.
• Confirm before entering sensitive data, submitting forms, uploading files, accepting browser permissions, changing sharing/access, or deleting data.

Detect and Start

# Initialize or refresh project detection.
revyl init --detect

# Start the dev loop for the default platform (iOS is the default).
revyl dev

When platform matters, make it explicit:

revyl dev --platform ios
revyl dev --platform android

If detection picks the wrong provider, force the provider during init instead of editing around a bad config:

revyl init --provider expo
revyl init --provider react-native

In monorepos, run Revyl from the actual app directory, not the workspace root. For example, use apps/mobile for an Expo app even if the repo root also has a .revyl/ directory.

Start or Attach

Use normal revyl dev for new work. Contexts are worktree-local; separate worktrees can each use the default context. If another loop is already running in the same worktree, Revyl auto-selects a safe branch/platform context name and prints it. Pass --context <name> only when deliberately targeting a known loop.

# New loop: let Revyl provision the device and choose any needed context name.
revyl dev

# Inspect or switch named contexts only when you need to target one explicitly.
revyl dev list
revyl dev use <name>
revyl dev --context <name>

Attach only when you are intentionally reusing an already-running device session:

# Reuse the current active session only when it is unambiguous.
revyl dev attach active --context <name>
revyl dev

# If multiple sessions exist, attach by explicit session id or index.
revyl dev attach <session-id> --context <name>
revyl dev attach <index> --context <name>
revyl dev

active is a convenience shortcut for the current running device session. Do not use it when multiple sessions exist or when the desired session is unclear. After attaching a session to a context, run revyl dev from that worktree to start the loop on that session, or pass --context <name> if you need to target the attached context explicitly.

Framework Guidance

• Expo: use the Revyl-managed relay and Expo dev client for JS/TS hot reload. Rebuild only when native config, native modules, SDK/native dependencies, permissions, or URL scheme registration changes. Try an external Expo tunnel only after screenshots or reports show the Revyl relay, app load, or HMR path failed. If repeated web auth is slowing stable Expo testing, install and use revyl-cli-auth-bypass; let it detect the stack and delegate to revyl-cli-auth-bypass-expo for Expo app code. Implement the test-only bypass in the app first, then add an auth_bypass section to .revyl/config.yaml (see Auth Bypass below) so revyl dev applies the launch vars and fires the revyl-auth deep link automatically.
• React Native bare: use the Metro relay. No app_scheme is needed because the device loads the JS bundle over the Revyl relay. JS/TS changes hot reload; native dependency, Podfile, Gradle, or native source changes need a rebuild. Do not use Expo tunnel fallback unless the app is actually an Expo dev-client flow.
• Flutter: use a rebuild-first loop. There is no Metro/Expo dev server for cloud hot reload; the binary is the app. revyl dev installs and runs the current build, and Dart file saves may auto-trigger rebuilds. In agent shells, use revyl dev rebuild --wait when an explicit rebuild is needed, then verify on the device.
• Native iOS/Swift and native Android/Kotlin: use a rebuild-first loop. Xcode, Gradle, Kotlin, Swift, resource, manifest, or native dependency changes must build, upload or delta-push, reinstall, and relaunch in the cloud session. Expo tunnels do not fix these stacks.
• KMP, Bazel, and other native artifact flows: treat the configured build.platforms.<key>.output artifact as the app. Iterate through the configured build command, revyl dev rebuild --wait, and device verification.
• Monorepos: if detection is confused by hoisted dependencies or nested native folders, run from the app directory and force the provider only when needed.

If repeated login slows exploration on any stack, use revyl-cli-auth-bypass first. It detects the app stack and delegates to the matching platform leaf before this dev-loop skill starts the session with bypass launch vars.

Observe, Act, Verify

Use screenshots and reports to decide what happened before changing strategy.

revyl device screenshot --out before.png
revyl device tap --target "Sign In button"
revyl device type --target "Email field" --text "[email protected]"
revyl device swipe --target "Product list" --direction down
revyl device instruction "Open the checkout screen"
revyl device screenshot --out after.png
revyl device report --session-id <session-id> --json

During exploration, capture the exact path that worked. Describe actions with visible target language and keep the path at intent level.

Auth Bypass

Preferred: configure it once in .revyl/config.yaml and every session — cold start, rebuild relaunch, reused session — launches authenticated with no flags:

auth_bypass:
  launch_vars: [REVYL_AUTH_BYPASS_ENABLED, REVYL_AUTH_BYPASS_TOKEN]
  deep_link: "myapp://revyl-auth?token=${REVYL_AUTH_BYPASS_TOKEN}&redirect=/home"

${VAR} placeholders resolve from org launch-variable values at fire time. The deep link fires automatically after every app (re)launch. If the app ever shows a logged-out state mid-session (expired mint), recover by re-minting the launch vars with the repo's own mint script (check the repo's AGENTS.md or scripts/), then re-firing the deep link with fresh values:

revyl dev auth refresh --json

Manual fallback (no config section yet):

# One-time setup if the launch vars do not already exist.
export REVYL_AUTH_BYPASS_TOKEN="<test-only-token>"
revyl global launch-var create REVYL_AUTH_BYPASS_ENABLED=true
revyl global launch-var create REVYL_AUTH_BYPASS_TOKEN="$REVYL_AUTH_BYPASS_TOKEN"

revyl dev --no-build \
  --launch-var REVYL_AUTH_BYPASS_ENABLED \
  --launch-var REVYL_AUTH_BYPASS_TOKEN

# After the app loads, open the auth-bypass link from a separate shell:
revyl device navigate \
  --url "myapp://revyl-auth?token=$REVYL_AUTH_BYPASS_TOKEN&role=buyer&redirect=%2Fcheckout"
revyl device screenshot --out /tmp/revyl-auth-bypass.png

If the app has not implemented the handler yet, install/use revyl-cli-auth-bypass first. It will delegate to the platform leaf (e.g. revyl-cli-auth-bypass-expo) for the app-side handler, then add the auth_bypass section to .revyl/config.yaml so future sessions need no manual steps. Never paste launch-var values into code, logs, or PRs.

Guardrails

1. Start from the detected app stack, then override only when detection is wrong.
2. Keep the dev loop running while using separate short-lived revyl device commands for interaction.
3. Prefer user-visible outcomes over implementation details.
4. Stop local loop cleanly with Ctrl+C or revyl dev stop when done.

Agent Execution

revyl dev is a persistent process. In agent shells, prefer --detach: the loop daemonizes itself and the command returns a machine-readable handshake as soon as the device session is live (the build may still be running behind it).

# Preferred agent start: returns JSON with viewer_url within seconds. On a
# local machine the CLI also opens the viewer in the user's browser
# (opened_browser in the handshake; --no-open disables). When opened_browser is
# false (headless/CI/SSH), always post viewer_url as a clickable link; never
# open a browser yourself.
revyl dev --remote --detach --json    # native / rebuild-first stacks
revyl dev --detach --json             # hot-reload stacks

# Optional: install the latest existing build immediately (seed) so the app is
# interactive + authenticated within seconds while the fresh build compiles,
# then it hot-swaps automatically. Best when time-to-first-build is slow.
revyl dev --remote --seed-latest --detach --json

# Share viewer_url with the user immediately, then monitor the BUILD:
revyl dev status                      # build_mode=remote; state: building -> idle
revyl dev logs --build --follow       # stream remote build output

# Iterate and stop:
revyl dev rebuild --wait --json       # signals the running loop (SIGUSR1); no separate build cmd
revyl dev stop --json

Do NOT combine --remote with --no-build or --tunnel (the CLI rejects both). --build-version-id is allowed with --remote only as an explicit seed source.

revyl dev status --wait-ready blocks until the device SESSION is live, which in --remote happens while the build is still running — it does NOT mean the build finished. Track build completion via dev status (building -> idle) or dev logs --build --follow. With --seed-latest, the handshake/status report installed_seed + seeded_version for the build already on screen.

If --detach is unavailable (older CLI), fall back to the environment's non-blocking shell mode:

1. Background long-running loops -- use the agent environment's non-blocking shell mode for revyl dev.
2. Poll for readiness -- Hot reload ready means the Expo/Metro transport is up; Dev loop ready, a viewer URL, or successful revyl device evidence means the full device loop is ready. If output stalls on device provisioning after Hot reload ready, debug the worker/device session path instead of changing the relay/tunnel strategy.
3. Detect failures early -- if the process exits or output contains Error: before the ready line, stop and report the error to the user.
4. Device commands in a separate terminal -- revyl device tap, screenshot, type, and swipe are short-lived. Run them in a different Shell call, not the dev-loop terminal.
5. Do not interact with TTY prompts -- the dev loop prints [r] rebuild native + reinstall and [q] quit. These require a real TTY. In agent shells, use revyl dev rebuild, revyl dev stop, or restart the loop instead.
6. Attaching to an existing session -- if no suitable session exists, run revyl dev normally and let Revyl choose the context. If exactly one relevant current session exists, attach it with revyl dev attach active --context <name>, then start with revyl dev. If multiple sessions exist, use an explicit session id or index; do not guess.
7. Keep logs concise -- use revyl dev --debug only for relay/HMR troubleshooting. When reporting results, summarize the state transitions and include only the first actionable error, relevant relay/session IDs, and a small log tail. Do not paste long spinner output or full debug streams unless the user asks for raw logs.

Cloud Agent Relay Note

In Cursor or similar cloud-agent environments, start with the Revyl-managed relay:

revyl dev --no-build --app-id <app-id>

If you need to target a specific existing loop, inspect contexts first with revyl dev list, then run revyl dev --context <name>. Do not predefine a context for normal startup; Revyl will pick one when the worktree needs it.

For Expo and bare React Native, this lets Revyl own Metro/Expo startup, relay creation, dev-client install, and the deep link opened on the cloud device. If the app does not load or hot reload does not apply changes, gather device evidence before changing transport.

If startup fails with failed to create relay session: unauthorized after Backend relay connectivity OK, do not assume the developer needs to log in again. First run revyl auth status and revyl ping; if both pass, capture a revyl dev --debug run and treat it as a Revyl relay/backend issue. For Expo dev-client projects, use --force-hot-reload first when Revyl verifies relay transport but cannot prove Expo manifest readiness.

After Dev loop ready, keep the process running. Treat Viewer: and the relay/deep-link host printed by revyl dev as the active relay session; in production this may be relay.revyl.ai, while local or branch environments may use a generated relay/ngrok host. Do not stop the relay because of HMR diagnostic warnings; normal runs hide advisory HMR diagnostics, and revyl dev --debug is for relay/HMR troubleshooting.

If startup fails because the relay transport is not ready yet (slow Metro startup on large apps), extend the readiness wait instead of switching transports:

revyl dev --platform ios --ready-timeout 120   # seconds; or set REVYL_READY_TIMEOUT

If relay transport and manifest checks pass but a large Expo app times out on the first cold bundle transform, extend the separate prewarm budget (default 300 seconds, maximum 600):

revyl dev --platform ios --prewarm-timeout 600 # or set REVYL_PREWARM_TIMEOUT

Metro inherits your shell environment (for example EXPO_OFFLINE=1 speeds up Expo startup); CI is intentionally stripped from the Metro environment because CI=1 disables Fast Refresh.

For Expo manifest readiness timeouts, use diagnostic launch mode before switching transports:

revyl dev --platform ios --force-hot-reload

This still requires Expo startup and Revyl relay transport to succeed. It skips only the manifest and bundle proof so the cloud device can be the source of truth. If the app loads, keep working. If the dev client shows a project load error, restart Expo/Metro or capture a report.

Before switching to Expo tunnel fallback, gather device evidence:

revyl device screenshot -s <session-index>
revyl device report --session-id <session-id> --json

Continue using the relay if screenshots show the app downloading/loading or the report/network evidence shows successful fetches from the relay host printed by revyl dev. Only fall back for Expo/React Native dev-client projects if the device remains on a dev-client error screen, the report shows no successful relay fetches, or the app loads but hot reload is not applying changes.

For Flutter, Swift/iOS, native Android, KMP, Bazel, and other rebuild-first stacks, do not switch to an Expo tunnel. These stacks do not use the Metro/Expo transport path. If changes do not appear, inspect revyl dev status, the last build output, and the device screenshot. Then trigger revyl dev rebuild --wait from a separate shell, or stop and restart the loop if the rebuild session is unhealthy.

If fallback is needed, start Expo in a long-running terminal and pass the full dev-client link that Expo prints, not just the raw *.exp.direct URL:

CURSOR_AGENT=1 npx expo start --tunnel --dev-client
revyl dev --no-build --app-id <app-id> --tunnel '<full Expo dev-client link>'

Shell(command="revyl dev --no-build --app-id <app-id>", block_until_ms=0)
AwaitShell(pattern="Dev loop ready", block_until_ms=120000)

# Or attach to an existing context
Shell(command="revyl dev list")
Shell(command="revyl dev attach active --context <name>")
Shell(command="revyl dev --context <name>", block_until_ms=0)
AwaitShell(pattern="Dev loop ready", block_until_ms=120000)

Shell(command="revyl device screenshot")
Shell(command="revyl device tap --target 'Login button'")