{
  "context": "This criteria evaluates how well the engineer uses aioredis string operations to implement a session token manager. The focus is on proper usage of Redis commands for storing tokens with expiration, batch operations, existence checking, and key deletion.",
  "type": "weighted_checklist",
  "checklist": [
    {
      "name": "Token expiry usage",
      "description": "Uses setex() or set() with ex parameter to store tokens with automatic expiration in store_token(). Does not manually track expiration or use separate expire() calls.",
      "max_score": 25
    },
    {
      "name": "Batch set operations",
      "description": "Uses mset() to store multiple tokens atomically in store_tokens(). Properly handles setting expiration for all tokens after mset, either through pipeline or multiple setex calls if mset+expiry is not directly available.",
      "max_score": 20
    },
    {
      "name": "Single get operation",
      "description": "Uses get() method correctly in get_token() to retrieve a single token value. Properly handles None return for non-existent keys.",
      "max_score": 10
    },
    {
      "name": "Batch get operations",
      "description": "Uses mget() to retrieve multiple token values atomically in get_tokens(). Correctly maps user_ids to retrieved values and handles None values for missing keys.",
      "max_score": 15
    },
    {
      "name": "Existence checking",
      "description": "Uses exists() method in token_exists() to check if a session key exists. Returns proper boolean value.",
      "max_score": 10
    },
    {
      "name": "Single key deletion",
      "description": "Uses delete() or unlink() method correctly in delete_token() to remove a single session key.",
      "max_score": 10
    },
    {
      "name": "Batch deletion",
      "description": "Uses delete() or unlink() with multiple keys in delete_tokens() to remove multiple session keys in a single operation.",
      "max_score": 10
    }
  ]
}