Start at the last confirmed app state and find the first transition that did not happen. A successful tap, a dismissed spinner, or an agent saying “done” does not prove the requested change occurred: verify the result in the app UI or in trustworthy app data available to the integration. Then use screenshots, accessibility information, logs, and network evidence to identify whether the failure is in task interpretation, UI interaction, permissions, SDK setup, authentication, or connectivity.
1. Reproduce the failure and define what success looks like
Capture the conditions before changing anything. Record the exact request, app version and build, operating system and device or simulator, agent or SDK version, account state, and whether the failure happens consistently. Reduce the task to the shortest sequence that still fails.
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For each step, write down the expected visible result and the actual result. For example, “tap Save” is an action; “the updated address is visible on the profile screen after saving” is a verifiable outcome. Keep the requested task and its proof separate: the agent may carry out an action without producing the intended side effect.
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For Firebase App Testing agent, Firebase recommends splitting complex tasks into shorter sequential steps and adding a final-screen assertion that describes what should be visible. This guidance is specific to that tool, not a universal requirement for every agent. Firebase App Testing agent documentation
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2. Locate the first divergence between the expected and observed state
Inspect the last screenshot or accessibility snapshot before the agent went off course. Compare the target it selected with the control you intended it to use, then check whether the screen actually changed after the action.
- Was the intended control present, visible, labeled, exposed to accessibility, and actionable?
- Did a modal, OS permission prompt, keyboard, loading screen, or other surface take focus?
- Did the control respond but leave the app in the same state, or did the action never appear to occur?
- Could the agent have missed a scrollable region or an item that only appears after scrolling?
On iOS, XCTest and XCUIAutomation provide element queries, snapshots, waits, and state checks; XCTest can also monitor unrelated UI interruptions that block controls under test. These are iOS testing tools and do not diagnose other integrations by themselves. Apple’s UI testing documentation
When the agent appears to see the wrong screen
For Firebase App Testing agent, enable “Show agent view” to inspect the elements it detected through accessibility information, then review the test video, logs, and other run artifacts. Firebase documents scrolling problems, especially when a page provides no visual indication that it scrolls; a prompt hint can suggest scrolling. Its preview also cannot navigate apps using FLAG_SECURE, which appear blank to the agent. These constraints apply to that Firebase preview only. Firebase App Testing agent documentation Firebase App Testing agent limitations
3. Check whether the agent has a valid way to perform the action
First establish how the integration acts: by interpreting and operating the screen, or by calling a declared app capability or API. A visually plausible task can still fail if the chosen path is unsupported or permission-gated.
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Android AppFunctions
If the integration uses Android AppFunctions, confirm the device is running Android 16 or higher, that the relevant function is available and enabled, and that the caller has EXECUTE_APP_FUNCTIONS permission to discover and execute functions. Android describes AppFunctions as experimental-preview technology, so check current availability for the specific workflow rather than assuming general support. Android Developers: AppFunctions
Android AccessibilityService
If an Android AccessibilityService is involved, check that it is enabled and that its use complies with Google Play policy. Google Play requires a narrow, clearly understood purpose for general automation and 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. These are platform policy requirements, not ways to bypass a broken interaction. Google Play AccessibilityService policy
4. Verify mobile SDK setup and runtime context
If a vendor’s mobile SDK is involved, check its integration before treating the failure as a model or app-UI problem. Verify that the native bridge or module is linked into the build, required initialization completed before any bridge call, configuration values are correct, and the intended agent or deployment is active. Also check whether the app must be in the foreground when the task starts.
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Salesforce’s Agentforce React Native guidance illustrates how specific these checks can be: its iOS setup includes installing pods and opening the workspace; Android setup includes registering the package; deployment names are case-sensitive; configure() must complete before launch; and launch should come from a foreground button handler rather than a background task. Apply those instructions only to that Salesforce SDK; other vendors have different setup requirements. Salesforce Agentforce React Native troubleshooting
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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.
- STANDARD OBD-II FUNCTIONS – read & clear trouble codes for check engine light, view freeze frame data, I/M readiness, and live sensor data to help monitor vehicle health and diagnose check engine problems.
- 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.
5. Check authentication and connectivity using evidence
Confirm the configured service URL is the API or service endpoint expected by the integration, not merely a login URL, and verify that the device can reach it. Review the SDK’s logger output, ideally from before initialization, alongside any request or response artifacts. A failure alone is not proof of a network problem: look for a failed request, an authentication error, or evidence that no request was issued.
Salesforce notes that an incorrect endpoint can produce a 400 error during session start or an indefinite loading spinner. For its Employee Agent authentication flow, Salesforce documents refreshing credentials and, if refresh fails, logging out and back in. Those remedies are Salesforce-specific; use the matching vendor guidance for other products. Salesforce Agentforce React Native troubleshooting
Expo agent-device can collect focused logs, available network requests and responses, UI state, screenshots, traces, and performance data. Use whatever artifacts your own tool exposes to distinguish among a request that never left the device, a failed request, and a successful response that was not reflected in the app UI. Expo agent-device documentation
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6. Confirm the side effect and make the rerun diagnostic
After making one targeted change, rerun the shortest reproducible case. Check the expected final state with an explicit visible assertion or reliable app state, rather than relying on the agent’s completion message. If the outcome still fails, compare the new evidence with the prior run to see whether the first divergence moved.
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For iOS, XCTest with XCUIAutomation can drive the UI, query elements, wait for app state, and assert expected properties. Expo agent-device can capture screenshots and record or replay a deterministic session. Firebase App Testing agent can replay successful action sequences, but the final assertion remains important; if replay fails, its preview can fall back to AI actions. These options apply only in their respective environments. Apple’s UI testing documentation Expo agent-device documentation Firebase App Testing agent documentation
Choose evidence that matches the likely failure layer
| Likely layer | Evidence to inspect | Useful next check |
|---|---|---|
| Task interpretation or UI perception | Screenshot or video, accessibility snapshot, selected element, action log | Find the first screen where the observed target differs from the intended target; verify labels, visibility, focus, and scrolling. |
| Capability or permission | Supported platform/version, function discovery and permission state, service status | Confirm the selected interaction mechanism is available and authorized in that environment. |
| SDK or runtime configuration | Initialization and native-module logs, build configuration, foreground/background context | Check linking, initialization order, deployment selection, and launch context against the specific vendor’s documentation. |
| Authentication or network | Credential state, service URL, request/response artifacts, SDK logger output | Establish whether the request was sent, whether the service responded, and whether authentication or reachability failed. |
| Unverified app-side effect | Final UI assertion or trustworthy app data available to the integration | Check the actual requested outcome after the action, independently of the agent’s completion claim. |
Choose the narrowest diagnostic that can produce evidence for the suspected layer. A manual reproduction can confirm the symptom; a short scripted UI test can establish a repeatable state check; a recorded deterministic flow can help compare runs. Do not assume a Firebase, Android, iOS, or Expo feature applies to a different agent or platform.
Firebase preview limits are not general agent limits
Firebase’s current App Testing agent preview documentation says AI-guided tests must succeed within five minutes or end early as failures. That is a limit of this preview, not a general timeout for mobile agents. The documented scrolling shortcomings, action set, and inability to navigate apps using FLAG_SECURE likewise describe Firebase’s preview and should not be generalized. Firebase App Testing agent limitations
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