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tessl-labs/frontend-error-handling

Proactive error handling for React and vanilla JS frontends — every data-fetching component gets loading, error, and empty states, error boundaries, fetch error handling, form validation, optimistic rollback

90

1.38x
Quality

84%

Does it follow best practices?

Impact

100%

1.38x

Average score across 5 eval scenarios

SecuritybySnyk

Passed

No known issues

Overview
Quality
Evals
Security
Files

criteria.jsonevals/scenario-5/

{
  "context": "Tests whether the agent proactively adds comprehensive error handling to a user profile page, without being told to. The task says nothing about error states, loading indicators, error boundaries, or retry -- the agent should apply these patterns on its own.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "Loading state while fetching profile",
      "description": "The profile component renders a visible loading indicator (spinner, skeleton, 'Loading...' text, or aria-busy) while the user data API request is in progress, not a blank screen.",
      "max_score": 14
    },
    {
      "name": "Error state with retry for profile",
      "description": "When the profile fetch fails, the component shows a user-friendly error message and a retry/try-again button so the user can re-attempt the load.",
      "max_score": 16
    },
    {
      "name": "Error state uses role=alert",
      "description": "The error message container uses role=\"alert\" so screen readers announce the error to users. The task said nothing about accessibility.",
      "max_score": 12
    },
    {
      "name": "Fetch handles network errors",
      "description": "The fetch call is wrapped in try/catch or .catch() to handle network errors (server unreachable, no internet) rather than letting the promise rejection go unhandled.",
      "max_score": 14
    },
    {
      "name": "Fetch handles HTTP errors",
      "description": "The code checks res.ok or res.status after fetch and handles non-2xx HTTP responses (4xx/5xx) as errors instead of silently treating them as success.",
      "max_score": 14
    },
    {
      "name": "User-friendly error messages",
      "description": "Error messages shown to users are human-readable strings (e.g., 'Failed to load profile'), not raw Error objects, stack traces, or technical codes.",
      "max_score": 10
    },
    {
      "name": "Empty activity state handled",
      "description": "When the activity feed API returns an empty array, the component shows a meaningful message (e.g., 'No recent activity') rather than a blank area.",
      "max_score": 10
    },
    {
      "name": "Error boundary present",
      "description": "The app includes a React error boundary component that catches render-time errors and displays a fallback UI instead of a white screen.",
      "max_score": 10
    }
  ]
}

evals

tile.json