Poker is much more than just a game. It’s a proving ground for advanced machine reasoning, especially for evaluating the capabilities of LLMs in poker AI.
These features are problems for AI algorithms based on classical machine learning principles because all these features use the ability to think in time without time, bluff, and adapt. This is the reason we use poker as a yardstick to see how well an algorithm can perform in a game in which there is uncertainty and ambiguity.
Why Solvers Are Great Problem Solvers, But Not Instinct
The classical solvers are great at devising a balanced strategy where the aim is to discover a strategy that will prevent your opponents from being able to improve on the expected value (EV) in the long run at the tables. but they are not so good at making quick adjustments out of the emotions or instinct.
Human players on the other hand are great at making adjustments according to what is happening in the course of the game, and they tend to think instinctively or out of emotion in adjusting their strategies.
Why ToolPoker Was Invented for LLMs in Poker AI

As LLMs in poker AI continue to face the knowing-doing gap, new approaches are needed. The researchers invented ToolPoker to try to combine the best of both solvers (balance and non-exploitable) and the players (instinct) and adaptability.
The researchers did an experiment to compare the performance of six models at two games. The first game is a simplified version of poker called Leduc Hold’em. The second game is a version of Limit Texas Hold’em which presents more realistic poker games. Six different models (GPT-4, Qwen 2.5, LLaMA 3, o4-mini, and the baseline solvers: CFR+, NFSP) were given the same parameters and stakes and were judged on their performance on three criteria:
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HR (Hand Rationality): How much does the model reason like a professional player?
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FA (Final Action): Did the model make the GTO (game theoretic optimal) move?
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AC (Average Chips): Did the model win?Why the Researchers Wanted to Test the LLMs Initially Before Making the Decisions
In order to understand how well the models would do the researchers had each model explain why it wanted to make a particular decision prior to making that decision. The results were astounding; many of the models gave perfect reasons for their decisions but then proceeded to make the opposite decision.
This phenomenon has been called the “knowing-doing gap” that is the difference between knowing something on an intellectual level and doing something on a practical level.
Three Major Ways LLMs Still Fail in Poker
While the researchers have improved LLMs with reinforcement learning (RL) training, they still possess great flaws as poker players. Heuristics-Based Logic
LLMs tend to rely on familiar linguistic heuristics. For example, a model may decide to bet aggressively in a situation because it has been exposed to examples of situations in which aggressive betting is successful even though the current situation may be very different. Poor Understanding of Mathematical Nuances
LLMs seem to understand mathematical concepts like pot odds and implied odds. But when it comes to employing those calculations in practice, they tend to be inconsistent.
Mot that an LLM will utilize a logical process to evaluate a decision to make, but that does not mean that it will execute that decision in the way that it ought to . This is due to the fact that the LLM makes a distinction between “the logical thought process it took to come to that decision” and “the actions it takes which flow logically from that decision.”
What ToolPoker Offers for LLMs in Poker AI
To improve the reliability of LLMs in poker AI, researchers introduced ToolPoker. It permits an LLM to take a break in the middle of a poker hand and consult a solver. Then when the LLM gets the benefits of the solver’s advice, it integrates that advice into its cognitive process for rendering the decision.
Think of ToolPoker like giving an overly-conversational student a crib-sheet, but only after they are able to give coherent and logical reasons for the answers generated by the crib sheet.
Here is how ToolPoker is used:
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<think> – gives logic for the train of thought taken by the model
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<tool>– consults a solver for GTO Advice
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<output>– evaluates equity, pot odds and best possible move(s)
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<answer>– acts, synching thought and deed
ToolPoker’s structured approach permits the separation of ‘hallucinations,’ so that the LLM’s developed reasoning tracks with the reasoning it puts to use subsequently in action.
Training LLMs in Poker AI with ToolPoker

ToolPoker is trained employing the two phased training methodology outlined:
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Behavioral Cloning (BC): The LLM learns from annotated pro level reasonings plus solver use.
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Reinforcement Learning (RL): Models are rewarded for accuracy of decisions, correctness of reasoning structure and correctness of tool usage.
Together, these phases guarantee that the model’s reasoning is both fluid and action-reachable. Performance Assessment
ToolPoker outperformed DQN and NFSP by greater than 60 chips in both games. It was within 3-5 chips of CFR+, in other words tied, when human-level variability is accounted for.
In terms of the quality of the explanation, ToolPoker’s performance was rated:
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Hand Rationality (HR) was rated 2.0/2.0 which indicates expert reasoning.
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Final Action Consistency (FA) was rated 1.9/2.0 indicating very strong correlation with optimum play.
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Quality of the Reasoning Trace: Tool Poker’s traces were judged by human reviewers to be indistinguishable from those of a professional player using a solver.Comparing Humans vs LLMs in Poker AI
The results of ToolPoker’s decisions in comparison with professional poker players yielded the following ratings:
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ToolPoker was the earth’s equivalent of matching 92 – 97% of expert EV (expected value).
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Professional Poker players characterized ToolPoker’s play as being “on a par with” or “more clearly explained” than human commentators play in 70% of cases.
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In 30% of the cases professional players rated ToolPoker’s play as “too good” missing the flexible aspect characterized by a human.
In many cases, human pros now acknowledge the strength of LLMs in poker AI when combined with solver support. The characterization of ToolPoker as “too good” is important. It means that ToolPoker has no ego to serve, makes no bluff plays nor any tilt. It simply plays the math of the hand perfectly – each and every hand.
What ToolPoker Can’t (Yet) Do
While ToolPoker indeed is a great improvement in AI performance in respect to poker it has certain limitations:
No Psychologica
l Model for Handling Opponents
ToolPoker does not adjust for loose opponents nor does it utilize tilt. As such, it is completely GTO reliant as such even when deviating from GTO would give it a greater EV.
Dependence on Solver
ToolPoker needs real time access to a solver in order to function. As such, it really is not scalable and the time for it to make decisions is longer than it could be because of this dependence.
Risk of Use
If left unchecked ToolPoker could facilitate RTA (real time assistance) cheating in live poker. Essentially an RTA bot which would use a solver to find the best decision in real time and send it to the player also in real time.
To eliminate this risk, the researchers have suggested audit trails, watermarking of the output of the solver and the implementation of ethics layers. Most importantly, they explicitly reject the idea of commercialization of the product and suggest strict regulation and control of its use.
LLMs in Poker AI: Why It Matters Beyond Poker
The impact of LLMs in poker AI goes far beyond the poker table. ToolPoker is much more than a poker playing AI. It represents a blueprint for developing AI systems that:
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Think in a structured sequential manner.
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Effectively use tools.
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Have a transparent reasoning basis for their decisions.
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Make high risk/high stakes decisions with transparent accountability.
Some areas where it could conceivably be applied include:
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Finance: Automatic bids, fair price of a given market.
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Policy: Adversarial negotiation models.
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Cybersecurity: real time response models with full explainability.
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Law and Medicine: Auditable models with human oversight.
In short poker is being used as a testing ground for AI accountability.
Synthetic Rationality and The End of Intuition
ToolPoker does not bluff, tilt or guess. It calculates. While it may lack the intuition of a human player, its calculation capabilities vastly outstrip that of the human player.
The authors try to define this by calling it synthetic rationality – the ability to reason without the benefit of experience and be able to make that reasoning known clearly.
They do not call the new systhesis the end of intuition, but the beginning of a new role for human intuition the editor, curator or overseer of AI systems.
p.s. updated:
PokerBattle.ai: A Live Head‑to‑Head of LLM Poker “Reasoning”
A head-to-head live test of the “reasoning” of top LLM’s poker strategy was conducted through PokerBattle.ai as a no-limit Texas Hold’em cash game lasting one week in which all models were given the same input prompts and played against each other without access to code or tools. All models were provided with their own “live” summary of their thought process throughout the session and were also given a “fold when I fail” feature to avoid taking unnecessary risks. At the end of the seven days of heads up competition, the three models had logged 3,799 hands each at 10/20 blinds, with both models beginning with equal bankrolls. The results of the event were that OpenAI’s o3 model won the most money ($36,691), followed by Claude Sonnet 4.5 who earned $33,641 and Grok who won $28,796. Meta Llama 4 lost the most money (-$100,000) and thus last place. This wide disparity in performance is evidence of a significant difference in the level of consistency and risk management between the four models. (About; Event Results) The event generated considerable interest — including front-page discussion at Hacker News regarding the strategic consistency of LLM’s and the randomness of LLM’s decisions, and even a tweet from Elon Musk boosting Grok’s brief lead — generating a large amount of debate and speculation about whether the current crop of LLM’s are capable of sustaining a GTO-like strategy that incorporates elements of both exploitable and non-exploitable mathematics/format-based errors in order to outperform humans at the table. (Reddit; PokerOrg recap of the event including the final standings; PokerNews coverage of the event.) In its design, PokerBattle.ai represents an innovative type of “open” comparison designed to provide an apples-to-apples evaluation of the “publicly available” decision-making processes of LLM’s that has been evaluated using solvers and/or dominant algorithms, but this time, PokerBattle.ai focuses on providing a publically accessible and inspectible view of the reasoning traces used by LLM’s to make decisions during the competition. Therefore, PokerBattle.ai serves as a timely reality-check: today’s general-purpose LLM’s have the ability to provide logical explanations of how they are thinking and adapting based upon prior experiences (via “notes”) however they continue to be unable to demonstrate the robustness and equilibirum-aware play necessary to beat professional players at the table on a regular basis. As such, it appears that PokerBattle.ai will likely be useful for instructional purposes and for analytical purposes related to understanding how LLM’s think about poker, but much less useful for developing models that can compete with professionals at the table on a regular basis.



