Start with the last confirmed app state and identify the first step that did not happen. A model saying “done,” a successful tap, or a dismissed spinner does not prove the requested change was saved. Confirm the result in the app’s visible UI or in trustworthy app data available to your integration.
Then work through the failure in layers: task definition, what the agent saw and did, capabilities and permissions, SDK setup, authentication, and network requests. The platform-specific checks below apply only when you use that platform or integration.
1. Reproduce the failure and define success
Write down the exact request and the result that would prove it is complete. Reduce a long task to the shortest sequence that still fails, then record what should be visible after each step and what actually appears.
- Record the app version or build, operating system, device or simulator, agent/tool version, and account state.
- Note whether the failure happens every time or only under particular conditions.
- Separate actions from outcomes: “tap Save” is an action; “the saved item appears in the list after reopening it” is evidence of an outcome.
For Firebase App Testing agent, Firebase recommends breaking complex tasks into shorter sequential steps and using a final-screen assertion that describes what should be visible. See Firebase’s agentic test documentation.
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2. Find where the agent’s observed state diverged
Inspect the last screenshot or accessibility snapshot before the failure. Compare the target the agent selected with the control that should have been used. Check whether the target was present, visible, labeled, exposed to accessibility, and actionable—and whether the screen changed after the action.
Look for a modal, keyboard, loading state, OS permission prompt, or other surface that may have taken focus. A tap can be delivered successfully while the app ignores it or applies it to a different control.
Firebase App Testing agent
Enable Show agent view to inspect the elements detected through accessibility information, then review the run’s video, logs, and other cloud artifacts. Firebase documents scrolling problems, particularly on pages without a visible cue that more content is available; a task hint can suggest scrolling. Its preview also cannot navigate apps that use FLAG_SECURE, which appear blank to the agent. These limitations are specific to Firebase’s preview, not mobile agents generally. See Firebase’s agentic test documentation and Firebase’s troubleshooting guidance.
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iOS UI automation
If you are diagnosing an iOS workflow with XCTest, XCUIAutomation provides element queries, snapshots, and state checks. XCTest can also monitor unrelated UI interruptions that block controls under test. Use these tools to determine whether the expected control existed and whether the app reached the expected state; see Apple’s XCUIAutomation documentation.
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First determine whether the integration operates the app through screen automation or calls a declared app capability/API. A screen agent cannot invoke a capability it does not have, and a capability-based integration can fail even when the UI looks correct.
Android AppFunctions
If the workflow uses Android AppFunctions, confirm the device runs Android 16 or higher, the function is available and enabled, and the caller has EXECUTE_APP_FUNCTIONS permission to discover and execute it. Android Developers describes AppFunctions as experimental-preview technology, so check current availability for the specific workflow. See Android’s AppFunctions overview.
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- NOTE: It requires a compatible third-party app and is designed primarily for standard OBD-II diagnostics. It is not a full-system scanner. Advanced or vehicle-specific functions depend on your vehicle and the app. Please check compatible apps and supported functions before purchase.
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- VEHICLE COMPATIBILITY – Works with most 1996+ cars and light trucks in the US for standard OBD-II diagnostics functions. Support for EVs & PHEVs is app-dependent; please use Apps developed for EVs such as Car Scanner ELM OBD2 to check compatibility or contact Veepeak.
- EASY BLUETOOTH CONNECTION: Supports Bluetooth LE for iOS & Android (not WiFi): please connect from within the app after setting the correct connection type. Also supports classic Bluetooth mode for Android. Android head units may not be supported.
- APP COMPATIBILITY: Compatible with generic Apps including Car Scanner ELM OBD2, Torque (for Android), OBD Fusion, as well as vehicle-specific Apps like BimmerCode*, BimmerLink*, OBD JScan, Dr. Prius, OBDocker, etc. Note: some Apps or in-App features require separate purchase from third party developers. NOT compatible with Carly, MHD, xHP, ProTool, bootmod3, etc.
Android AccessibilityService
If the integration relies on an AccessibilityService, verify that the service is enabled and that its use complies with Google Play policy. Google Play requires a narrow, clearly understood purpose for general automation; it prohibits using AccessibilityService to let general apps autonomously initiate, plan, and execute actions or decisions. Apps that do not qualify as accessibility tools must provide prominent in-app disclosure and obtain affirmative consent. Policy compliance is a requirement, not a workaround for a failing task. See Google Play’s AccessibilityService policy.
Independent reader supportYour contribution helps us test, update, and keep practical guides available for everyone.4. Check SDK setup and runtime context
When a mobile SDK is involved, verify that the native module is linked and included in the build, required initialization runs before bridge calls, configuration is complete, and the service or agent deployment is active. Also check whether launch requires the app to be in the foreground.
For example, Salesforce’s Agentforce React Native SDK troubleshooting guidance calls out iOS pod installation and opening the workspace, Android package registration, a correct case-sensitive deployment name, awaiting configure() before launch, and starting the agent from a foreground button handler rather than a background task. These are Salesforce-specific checks; use the equivalent setup instructions for another SDK. See Salesforce’s React Native troubleshooting guide.
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- Easy to Carry: Thanks to its compact size and practical storage solution, this tester fits easily into any tool kit and can be taken anywhere without adding bulk or complexity during use.
- Ease of Use: Designed for immediate accessibility, this motherboard coil tester offers an intuitive step-by-step guide that supports users of all experience levels thanks to simplified procedures and a straightforward interface, ensuring smooth without the need for prior training
5. Verify authentication, endpoint, and connectivity
Check the exact service endpoint configured in the app; do not substitute a login URL. Confirm that the device can reach the service and that HTTPS requirements are met. Capture the SDK logger output before initialization where possible, then inspect available request and response artifacts to establish whether the request was never sent, failed, or succeeded without a corresponding UI update.
Salesforce documents that an incorrect endpoint can produce a 400 during session start or an indefinitely loading spinner. For its Employee Agent authentication, the documented recovery is to refresh credentials explicitly and, if refresh fails, log out and back in. Apply those remedies only to that Salesforce integration; follow the relevant vendor guidance for other agents. See Salesforce’s troubleshooting guide.
For an Expo workflow, agent-device can collect UI state, screenshots, focused logs, available network requests and responses, traces, and performance data. Use the artifacts to locate a failed transition rather than assuming that a task failure proves a network problem. See Expo’s agent-device documentation.
6. Rerun and verify the side effect
After changing one likely cause, rerun the shortest reproducible case. Verify the requested outcome with a visible assertion or trustworthy app state—not with the agent’s final message alone. On iOS, XCTest with XCUIAutomation can drive the interface, wait for app state, and assert element properties. Expo agent-device can capture screenshots and record or replay a deterministic session. Firebase’s App Testing agent may replay successful action sequences, but the final assertion remains important; replay can fall back to AI actions. See Apple’s XCUIAutomation documentation, Expo’s agent-device documentation, and Firebase’s agentic test documentation.
What Firebase’s preview limits mean
Firebase’s App Testing agent documentation says AI-guided tests must succeed within five minutes or end early as failures. That is a timeout for this preview, not a general limit for AI agents. The same preview’s documented scrolling and FLAG_SECURE limitations should likewise be treated as Firebase-specific. See Firebase’s troubleshooting guidance.
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