BlackjackEnv

Description

BlackjackEnv is an environment for evaluating agents on the classic card game. This environment wraps the Blackjack implementation from TextArena, a framework for text-based game environments.

Capabilities

• Strategic decision-making under uncertainty
• Risk assessment and probability reasoning
• Game theory and optimal play strategies

Compute Requirements

Blackjack does not require a sandbox. It has minimal compute requirements.

License

MIT.

Tasks

There are two splits: train (100 tasks) and test (100 tasks). Each split contains 50 tasks across each of 2 variants:

• Blackjack-v0: Standard blackjack game
• Blackjack-v0-long: Extended version with more rounds

Each task is seeded for reproducibility.

Reward Structure

This is a sparse reward environment. Rewards are mapped from TextArena's native range of {-1, 0, 1} to {0.0, 0.5, 1.0} via (raw + 1) / 2.

We do not use LLM graders for this environment; reward is determined programmatically.

Data

Game state is generated procedurally by the TextArena engine using seeded randomness. No external data files are required.

Tools

Agents are given two tools:

• hit(): Draw another card. Risk going over 21 (bust).
• stand(): Hold your current hand. The dealer will then draw cards.

Time Horizon

Blackjack is a multi-turn environment.

Environment Difficulty

Medium. The game requires understanding of basic probability and risk management, with decisions becoming more complex as the hand progresses.

Other Environment Requirements

There are no further environment requirements; Blackjack works out of the box without any secrets or API keys.

Safety

Agents in Blackjack interact only with a card game and have no access to external systems, the internet, or sensitive data. The environment does not present safety risks.

Citations

@software{textarena2024,
  author    = {Guertler, Leon and Banting, Wilfried and Pignatelli, Eduardo},
  title     = {TextArena},
  year      = {2024},
  publisher = {GitHub},
  url       = {https://github.com/LeonGuertler/TextArena}
}