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tessl-labs/flask-best-practices

Flask patterns -- application factory, blueprints, error handlers, extensions, request lifecycle, configuration, logging, CLI commands

98

1.28x
Quality

98%

Does it follow best practices?

Impact

98%

1.28x

Average score across 5 eval scenarios

SecuritybySnyk

Passed

No known issues

Overview
Quality
Evals
Security
Files

criteria.jsonevals/scenario-2/

{
  "context": "Tests whether the agent follows Flask best practices for request lifecycle hooks (before_request, after_request), flask.g usage, and proper project structure when building an event registration API.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "create_app factory",
      "description": "app/__init__.py defines a create_app() function that creates and returns a Flask app -- not a module-level app",
      "max_score": 10
    },
    {
      "name": "Blueprints for routes",
      "description": "Events and registrations routes use separate Blueprint objects in separate files under app/routes/",
      "max_score": 8
    },
    {
      "name": "before_request sets request ID on g",
      "description": "A before_request hook reads X-Request-ID from request headers (or generates a UUID) and stores it on flask.g -- not a module-level variable",
      "max_score": 10
    },
    {
      "name": "after_request returns response with request ID",
      "description": "An after_request hook adds the X-Request-ID header to the response AND returns the response object (not forgetting the return)",
      "max_score": 10
    },
    {
      "name": "Custom exception hierarchy",
      "description": "Agent defines AppError base class with subclasses (NotFoundError, ValidationError, or similar) and routes raise these exceptions",
      "max_score": 10
    },
    {
      "name": "Consistent error envelope",
      "description": "All error responses use {\"error\": {\"code\": \"...\", \"message\": \"...\"}} shape",
      "max_score": 8
    },
    {
      "name": "Extensions init_app pattern",
      "description": "Extensions are instantiated in extensions.py without app and bound via init_app() in the factory",
      "max_score": 8
    },
    {
      "name": "Error handlers in factory",
      "description": "Error handlers are registered centrally via register_error_handlers(app) called inside create_app()",
      "max_score": 8
    },
    {
      "name": "Generic exception handler logs error",
      "description": "Catch-all Exception handler logs with app.logger.exception() before returning 500",
      "max_score": 8
    },
    {
      "name": "Config from environment",
      "description": "Configuration uses environment variables with defaults, and create_app() accepts a config parameter for testing",
      "max_score": 8
    },
    {
      "name": "Per-request state on g not globals",
      "description": "All per-request state (request ID, DB connections, etc.) is stored on flask.g -- no module-level mutable globals used for request-scoped data",
      "max_score": 12
    }
  ]
}

evals

tile.json