/debug-app

name: debug-app
description: Use when the user has finished building a mobile app, started Metro with `npm run dev`, and wants the running app monitored for runtime errors AND silent failures (empty lists, blank screens, swallowed network errors) and fixed autonomously. Accepts a free-text symptom (e.g., `/debug-app "todos not appearing on home screen"`) to drive persisted-log diagnostics — injects temporary console.log statements at data-path boundaries, reads the sanitized `.powernative/metro-logs/` log, and cleans up logs after the root cause is fixed. Supports port/platform filtering, configurable clean-cycle and timeout limits, and watch-only `--no-fix` mode. Otherwise polls with a durable byte cursor, fixes inline or routes appropriately, verifies each fix from new output, and exits after the configured clean checks (default 3). Foreground loop — blocks the conversation while running. Run only after the app is loaded.
user-invocable: true
allowed-tools: Read, Edit, Write, Grep, Glob, Bash, AskUserQuestion, WebFetch, mcp__plugin_mobile-app_microsoft-learn__microsoft_docs_search
model: sonnet

**📋 Shared instructions: [shared-instructions.md](${PLUGIN_ROOT}/shared/shared-instructions.md)** — read first.

Debug App — Monitor & Fix

Monitor the running app through the project-local `.powernative/metro-logs/` files written by `metro.config.js`, detect runtime and bundle errors, and fix them autonomously by editing the affected files (or routing to the right skill when the fix belongs in a domain like Dataverse schema or auth registration). For silent failures, inject temporary `console.log` statements at data-path boundaries, read only newly appended log bytes, then clean the traces after the root cause is fixed. Modeled on the upstream `app-debugger.agent.md` pattern — foreground loop, bounded polling, configurable clean-check/timeout exits, and optional watch-only operation.

> **Dev-client limitation:** the standalone dev client sends app/runtime logs, React errors, host diagnostics, and Metro bundler output through Metro. The template's `metro.config.js` writes Metro terminal output and HTTP bundle failures into `.powernative/metro-logs/`; there is no separate device log source. Host diagnostics include strings such as `[AuthProvider] MSAL init failed:`, `[bridge] fetch THREW for`, `[bridge] HTTP <status> for`, `[addAadAppToConnectionAcl] failed HTTP <status> for connection`, `[useConnectionRefs] could not verify connection ACLs; treating existing connections as setup-required`, and `[PAHost][ErrorBoundary] Unhandled JS error:`.

Subcommands (parsed from `$ARGUMENTS`)

| Form | Behavior | |---|---| | `/debug-app` (no args) | **Default — project-log-driven mode.** Run Phase 0, discover valid project-local Metro sessions, select automatically when one is live or ask when several are live, then monitor the selected log. No host terminal ID is required. | | `/debug-app "<symptom text>"` | **Symptom-driven mode** (recommended when there's a user-visible problem). Free-text symptom such as `"todos not appearing on home screen"`, `"login button does nothing"`, `"list empty after refresh"`. Run Phase 0 → Phase 0.5 (parse symptom → ask the user to reproduce/navigate → walk the likely data path from terminal traces) → enter monitor loop. Catches silent failures (empty lists, blank screens, swallowed errors) that pure log polling misses. | | `/debug-app status` | Discover all project-local Metro logs and print each valid session's project, platform, PID, port, start time, and log path. Mark the session referenced by the saved cursor when present, then print fixes and unresolved errors. Do NOT ask for a selection or enter the loop. | | `/debug-app stop` | Stop only the foreground debug loop and preserve `.powernative/debug-app/` state. It does not stop Metro; the user owns the `npm run dev` process. | | `/debug-app version` | Print the installed `mobile-app` plugin name and version from `${PLUGIN_ROOT}/.plugin/plugin.json`, then exit. |

Monitoring options

Options may follow the default command, a symptom, or `status`:

| Option | Meaning | Default | |---|---|---| | `--working-dir <path>` | App root containing `package.json` and `metro.config.js`. Relative paths resolve from the current shell directory. | Current shell directory | | `--port <1-65535>` | Monitor only the valid Metro session on this port. | Any port | | `--platform <ios\|android>` | Consider only sessions whose recent log identifies this platform. | Any platform | | `--cycles <1-50>` | Exit after this many consecutive clean observation intervals. | `3` | | `--timeout <duration>` | Maximum wall-clock monitoring time. Accept `30s`–`60m` using `s`, `m`, or `h`. | `5m` | | `--no-fix` | Watch-only mode: classify and report, but never edit project source/config, inject traces, install dependencies, regenerate files, or invoke a mutating handoff. Debug cursor/audit/health state still advances. | Fix enabled |

Examples:

/debug-app --port 8082 --platform ios
/debug-app "orders screen is empty" --cycles 10 --timeout 15m
/debug-app --no-fix --timeout 30m
/debug-app status --platform android
/debug-app status --working-dir ../my-mobile-app

**Argument parsing:**

1. Parse quoted text as one symptom value and parse recognized flags wherever they appear. 2. The first reserved token (`status`, `stop`, `help`, `--help`, `-h`, `version`, `--version`) selects the subcommand. `stop`, help, and version do not accept monitoring options. `status` accepts only `--working-dir`, `--port`, and `--platform`; reject symptoms, `--cycles`, `--timeout`, and `--no-fix` because it does not enter the loop. 3. After removing recognized options and their values, any remaining non-reserved text is the symptom and enables symptom mode. 4. Reject unknown flags, duplicate flags, missing values, invalid numbers, unsupported platforms, or more than one free-text symptom. Print the valid forms and exit without monitoring. 5. Normalize `pla