# Explaining Reinforcement Learning Agents Through Counterfactual Action Outcomes

arXiv: https://arxiv.org/abs/2312.11118 · HTML: https://mlsanity.com/paper/2312.11118/

## Key facts

- Cited by 14 papers in the map (data through 14 Oct 2026).
- Builds on 18 of its 37 references that are in the map.
- First posted on arXiv 18 Dec 2023.

## Builds on (most cited first, 18 of 18)

- [Explanation in Artificial Intelligence: Insights from the Social Sciences](https://mlsanity.com/paper/1706.07269/) (2017)
- [Metrics for Explainable AI: Challenges and Prospects](https://mlsanity.com/paper/1812.04608/) (2018)
- [Explainable Reinforcement Learning Through a Causal Lens](https://mlsanity.com/paper/1905.10958/) (2019)
- [Visualizing and Understanding Atari Agents](https://mlsanity.com/paper/1711.00138/) (2017)
- [Proxy Tasks and Subjective Measures Can Be Misleading in Evaluating Explainable AI Systems](https://mlsanity.com/paper/2001.08298/) (2020)
- [Toward Interpretable Deep Reinforcement Learning with Linear Model U-Trees](https://mlsanity.com/paper/1807.05887/) (2018)
- [Hybrid Reward Architecture for Reinforcement Learning](https://mlsanity.com/paper/1706.04208/) (2017)
- [Interestingness Elements for Explainable Reinforcement Learning: Understanding Agents' Capabilities and Limitations](https://mlsanity.com/paper/1912.09007/) (2019)
- [Explain Your Move: Understanding Agent Actions Using Specific and Relevant Feature Attribution](https://mlsanity.com/paper/1912.12191/) (2019)
- [Establishing Appropriate Trust via Critical States](https://mlsanity.com/paper/1810.08174/) (2018)
- [Contrastive Explanations for Reinforcement Learning in terms of Expected Consequences](https://mlsanity.com/paper/1807.08706/) (2018)
- [Enabling Robots to Communicate their Objectives](https://mlsanity.com/paper/1702.03465/) (2017)
- [A Survey of Explainable Reinforcement Learning](https://mlsanity.com/paper/2202.08434/) (2022)
- [Local and Global Explanations of Agent Behavior: Integrating Strategy Summaries with Saliency Maps](https://mlsanity.com/paper/2005.08874/) (2020)
- [Exploring Computational User Models for Agent Policy Summarization](https://mlsanity.com/paper/1905.13271/) (2019)
- [Explaining Reinforcement Learning to Mere Mortals: An Empirical Study](https://mlsanity.com/paper/1903.09708/) (2019)
- [Contrastive Explanations for Reinforcement Learning via Embedded Self Predictions](https://mlsanity.com/paper/2010.05180/) (2020)
- ["I Don't Think So": Summarizing Policy Disagreements for Agent Comparison](https://mlsanity.com/paper/2102.03064/) (2021)

## Built on by (most cited first, 14 of 14)

- [Enhancing RL Safety with Counterfactual LLM Reasoning](https://mlsanity.com/paper/2409.10188/) (2024)
- [TalkToAgent: A Human-centric Explanation of Reinforcement Learning Agents with Large Language Models](https://mlsanity.com/paper/2509.04809/) (2025)
- [Interactive Explanations for Reinforcement-Learning Agents](https://mlsanity.com/paper/2504.05393/) (2025)
- [Explainable Reinforcement Learning Agents Using World Models](https://mlsanity.com/paper/2505.08073/) (2025)
- [Counterfactual Explanations for Continuous Action Reinforcement Learning](https://mlsanity.com/paper/2505.12701/) (2025)
- [Joint MDPs and Reinforcement Learning in Coupled-Dynamics Environments](https://mlsanity.com/paper/2603.06946/) (2026)
- [From Actions to Words: Towards Abstractive-Textual Policy Summarization in RL](https://mlsanity.com/paper/2503.10509/) (2025)
- [Ghost Policies: A New Paradigm for Understanding and Learning from Failure in Deep Reinforcement Learning](https://mlsanity.com/paper/2506.12366/) (2025)
- [STACHE: Local Black-Box Explanations for Reinforcement Learning Policies](https://mlsanity.com/paper/2512.09909/) (2025)
- [Contrastive explanations of BDI agents](https://mlsanity.com/paper/2602.13323/) (2026)
- [Not Every Divergence Should Be Suppressed: Counterfactual Recoverability in On-Policy Distillation](https://mlsanity.com/paper/2608.04408/) (2026)
- [Command-Space Counterfactual Explanations for Pareto-Conditioned Reinforcement Learning](https://mlsanity.com/paper/2608.14963/) (2026)
- [Evaluating RL Explainability Methods by How Much They Help Fix Bugs in Agents](https://mlsanity.com/paper/2608.17524/) (2026)
- [Visualizing the World Model in an Agent's Value Function](https://mlsanity.com/paper/2610.14186/) (2026)

## Abstract (arXiv)

Explainable reinforcement learning (XRL) methods aim to help elucidate agent policies and decision-making processes. The majority of XRL approaches focus on local explanations, seeking to shed light on the reasons an agent acts the way it does at a specific world state. While such explanations are both useful and necessary, they typically do not portray the outcomes of the agent's selected choice of action. In this work, we propose ``COViz'', a new local explanation method that visually compares the outcome of an agent's chosen action to a counterfactual one. In contrast to most local explanations that provide state-limited observations of the agent's motivation, our method depicts alternative trajectories the agent could have taken from the given state and their outcomes. We evaluated the usefulness of COViz in supporting people's understanding of agents' preferences and compare it with reward decomposition, a local explanation method that describes an agent's expected utility for different actions by decomposing it into meaningful reward types. Furthermore, we examine the complementary benefits of integrating both methods. Our results show that such integration significantly improved participants' performance.
