{
  "context": "This criteria evaluates an engineer's ability to use koa-route's regex-based path constraints feature to create selective routes that match specific patterns. The focus is on proper usage of the `:param(regex)` syntax to constrain path parameters to specific values or patterns.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "Admin exact match",
      "description": "Uses `route.get()` with path pattern `/:username(admin)` or equivalent regex to match exactly 'admin'",
      "max_score": 25
    },
    {
      "name": "Power user pattern",
      "description": "Uses `route.get()` with path pattern `/:username(power.*)` or similar regex to match usernames starting with 'power'",
      "max_score": 25
    },
    {
      "name": "Numeric ID constraint",
      "description": "Uses `route.get()` with path pattern `/:userId(\\d+)` or equivalent regex to match only numeric values",
      "max_score": 25
    },
    {
      "name": "Fallback unconstrained route",
      "description": "Uses `route.get()` with path pattern `/:username` (without regex constraint) to catch all other usernames",
      "max_score": 15
    },
    {
      "name": "Parameter extraction",
      "description": "Correctly extracts and uses the matched parameters in route handlers (e.g., `(ctx, username) => {}` or `(ctx, userId) => {}`)",
      "max_score": 10
    }
  ]
}