VLDB 2026 Research / reviewers in the wild / expert
Harsha Kokel
dblp:164/7457
· DBLP profile ↗
16ranked-venue papers
6as first author
15since 2021 · last 2026
0000-0002-7548-3719ORCID · corroborated
Domains — the database's venue-derived domains; a paper can count in several
Artificial intelligence and machine learning · 13 · 5 first-author · 12 since 2021Graphics, computer vision, multimedia, augmented reality and games · 8 · 4 first-author · 7 since 2021Databases, data management, data science and information retrieval · 2 · 1 first-author · 2 since 2021Applied, interdisciplinary, general and emerging computing · 1 · 1 since 2021
| Year | Publication | Venue | Position |
|---|---|---|---|
| 2026 | QueryGym: Step-by-Step Interaction with Relational DatabasesabstractWe introduce QueryGym, an interactive environment for building, testing, and evaluating LLM-based query planning agents. Existing frameworks often tie agents to specific query language dialects or obscure their reasoning; QueryGym instead requires agents to construct explicit sequences of relational algebra operations, ensuring engine-agnostic evaluation and transparent step-by-step planning. The environment is implemented as a Gymnasium interface that supplies observations---including schema details, intermediate results, and execution feedback---and receives actions that represent database exploration (e.g., previewing tables, sampling column values, retrieving unique values) as well as relational algebra operations (e.g., filter, project, join).We detail the motivation and the design of the environment. In the demo, we showcase the utility of the environment by contrasting it with contemporary LLMs that query databases. QueryGym serves as a practical testbed for research in error remediation, transparency, and reinforcement learning for query generation. Haritha Ananthakrishnan, Harsha Kokel, Kelsey Sikes, Debarun Bhattacharjya, Michael Katz 0001, Shirin Sohrabi, Kavitha Srinivas |
AAAI | 2 |
| 2025 | Automating Thought of Search: A Journey Towards Soundness and Completeness (Student Abstract)abstractLarge language models (LLMs) now turn their attention to search. Recently, Thought of Search (ToS) proposed defining the search space with code, having an LLM produce that code. ToS requires a human in the loop, collaboratively producing a sound successor function and goal test, achieving impressive 100% accuracy on all the tested datasets. In this work, we automate ToS (AutoToS), completely taking the human out of the loop of solving planning problems. AutoToS guides the language model step by step towards the generation of sound and complete search components, through feedback from both generic and domain specific unit tests. We achieve 100% accuracy, with minimal feedback iterations, using LLMs of various sizes on all evaluated domains. Daniel Cao, Michael Katz 0001, Harsha Kokel, Kavitha Srinivas, Shirin Sohrabi |
AAAI | 3 |
| 2025 | ACPBench: Reasoning About Action, Change, and PlanningabstractThere is an increasing body of work using Large Language Models (LLMs) as agents for orchestrating workflows and making decisions in domains that require planning and multistep reasoning. As a result, it is imperative to evaluate LLMs on core skills required for planning. In this work, we present ACPBench, a benchmark for evaluating the reasoning tasks in the field of planning. The benchmark consists of 7 reasoning tasks over 13 planning domains. The collection is constructed from planning domains described in a formal language. This allows us to synthesize problems with provably correct solutions across many tasks and domains. Further, it allows us the luxury of scale without additional human effort, i.e., many] additional problems can be created automatically. Our extensive evaluation of 21 LLMs and OpenAI o1 reasoning models highlight the significant gap in the reasoning capability of the LLMs. Our findings with OpenAI o1, a multi-turn reasoning model, reveal significant gains in performance on multiple-choice questions, yet surprisingly, no notable progress is made on boolean questions. Harsha Kokel, Michael Katz 0001, Kavitha Srinivas, Shirin Sohrabi |
AAAI | 1 |
| 2025 | TabSketchFM: Sketch-Based Tabular Representation Learning for Data Discovery Over Data LakesabstractEnterprises have a growing need to identify relevant tables in data lakes; e.g. tables that are unionable, joinable, or subsets of each other. Tabular neural models can be help-ful for such data discovery tasks. In this paper, we present TabSketchFM, a neural tabular model for data discovery over data lakes. First, we propose novel pre-training: a sketch-based approach to enhance the effectiveness of data discovery in neural tabular models. Second, we finetune the pretrained model for identifying unionable, joinable, and subset table pairs and show significant improvement over previous tabular neural models. Third, we present a detailed ablation study to highlight which sketches are crucial for which tasks. Fourth, we use these finetuned models to perform table search; i.e., given a query table, find other tables in a corpus that are unionable, joinable, or that are subsets of the query. Our results demonstrate significant improvements in F1 scores for search compared to state-of-the-art techniques. Finally, we show significant transfer across datasets and tasks establishing that our model can generalize across different tasks and over different data lakes. Aamod Khatiwada, Harsha Kokel, Ibrahim Abdelaziz, Subhajit Chaudhury, Julian Dolby, Oktie Hassanzadeh, Zhenhan Huang, Tejaswini Pedapati, Horst Samulowitz, Kavitha Srinivas |
ICDE | 2 |
| 2025 | Combining Planning and Reinforcement Learning for Solving Relational Multiagent Domains
Nikhilesh Prabhakar, Ranveer Singh, Harsha Kokel, Sriraam Natarajan, Prasad Tadepalli |
AAMAS | 3 |
| 2024 | Large Language Models as Planning Domain Generators (Student Abstract)abstractThe creation of planning models, and in particular domain models, is among the last bastions of tasks that require exten- sive manual labor in AI planning; it is desirable to simplify this process for the sake of making planning more accessi- ble. To this end, we investigate whether large language mod- els (LLMs) can be used to generate planning domain models from textual descriptions. We propose a novel task for this as well as a means of automated evaluation for generated do- mains by comparing the sets of plans for domain instances. Finally, we perform an empirical analysis of 7 large language models, including coding and chat models across 9 different planning domains. Our results show that LLMs, particularly larger ones, exhibit some level of proficiency in generating correct planning domains from natural language descriptions James T. Oswald, Kavitha Srinivas, Harsha Kokel, Junkyu Lee 0001, Michael Katz 0001, Shirin Sohrabi |
AAAI | 3 |
| 2024 | Partially Observable Hierarchical Reinforcement Learning with AI Planning (Student Abstract)abstractPartially observable Markov decision processes (POMDPs) challenge reinforcement learning agents due to incomplete knowledge of the environment. Even assuming monotonicity in uncertainty, it is difficult for an agent to know how and when to stop exploring for a given task. In this abstract, we discuss how to use hierarchical reinforcement learning (HRL) and AI Planning (AIP) to improve exploration when the agent knows possible valuations of unknown predicates and how to discover them. By encoding the uncertainty in an abstract planning model, the agent can derive a high-level plan which is then used to decompose the overall POMDP into a tree of semi-POMDPs for training. We evaluate our agent's performance on the MiniGrid domain and show how guided exploration may improve agent performance. Brandon Rozek, Junkyu Lee 0001, Harsha Kokel, Michael Katz 0001, Shirin Sohrabi |
AAAI | 3 |
| 2024 | Large Language Models as Planning Domain GeneratorsabstractDeveloping domain models is one of the few remaining places that require manual human labor in AI planning. Thus, in order to make planning more accessible, it is desirable to automate the process of domain model generation. To this end, we investigate if large language models (LLMs) can be used to generate planning domain models from simple textual descriptions. Specifically, we introduce a framework for automated evaluation of LLM-generated domains by comparing the sets of plans for domain instances. Finally, we perform an empirical analysis of 7 large language models, including coding and chat models across 9 different planning domains, and under three classes of natural language domain descriptions. Our results indicate that LLMs, particularly those with high parameter counts, exhibit a moderate level of proficiency in generating correct planning domains from natural language descriptions. Our code is available at https://github.com/IBM/NL2PDDL. James T. Oswald, Kavitha Srinivas, Harsha Kokel, Junkyu Lee 0001, Michael Katz 0001, Shirin Sohrabi |
ICAPS | 3 |
| 2024 | Thought of Search: Planning with Language Models Through The Lens of EfficiencyabstractAmong the most important properties of algorithms investigated in computer science are soundness, completeness, and complexity. These properties, however, are rarely analyzed for the vast collection of recently proposed methods for planning with large language models. In this work, we alleviate this gap. We analyse these properties of using LLMs for planning and highlight that recent trends abandon both soundness and completeness for the sake of inefficiency. We propose a significantly more efficient approach that can, at the same time, maintain both soundness and completeness. We exemplify on four representative search problems, comparing to the LLM-based solutions from the literature that attempt to solve these problems. We show that by using LLMs to produce the code for the search components we can solve the entire datasets with 100% accuracy with only a few calls to the LLM. In contrast, the compared approaches require hundreds of thousands of calls and achieve significantly lower accuracy. We argue for a responsible use of compute resources; urging research community to investigate sound and complete LLM-based approaches that uphold efficiency. Michael Katz 0001, Harsha Kokel, Kavitha Srinivas, Shirin Sohrabi |
NeurIPS | 2 |
| 2023 | Action Space Reduction for Planning DomainsabstractPlanning tasks succinctly represent labeled transition systems, with each ground action corresponding to a label. This granularity, however, is not necessary for solving planning tasks and can be harmful, especially for model-free methods. In order to apply such methods, the label sets are often manually reduced. In this work, we propose automating this manual process. We characterize a valid label reduction for classical planning tasks and propose an automated way of obtaining such valid reductions by leveraging lifted mutex groups. Our experiments show a significant reduction in the action label space size across a wide collection of planning domains. We demonstrate the benefit of our automated label reduction in two separate use cases: improved sample complexity of model-free reinforcement learning algorithms and speeding up successor generation in lifted planning. The code and supplementary material are available at https://github.com/IBM/Parameter-Seed-Set. Harsha Kokel, Junkyu Lee 0001, Michael Katz 0001, Kavitha Srinivas, Shirin Sohrabi |
IJCAI | 1 |
| 2023 | RePReL: a unified framework for integrating relational planning and reinforcement learning for effective abstraction in discrete and continuous domains
Harsha Kokel, Sriraam Natarajan, Balaraman Ravindran, Prasad Tadepalli |
Neural Comput. Appl. | 1 |
| 2022 | How to Reduce Action Space for Planning Domains? (Student Abstract)abstractWhile AI planning and Reinforcement Learning (RL) solve sequential decision-making problems, they are based on different formalisms, which leads to a significant difference in their action spaces. When solving planning problems using RL algorithms, we have observed that a naive translation of the planning action space incurs severe degradation in sample complexity. In practice, those action spaces are often engineered manually in a domain-specific manner. In this abstract, we present a method that reduces the parameters of operators in AI planning domains by introducing a parameter seed set problem and casting it as a classical planning task. Our experiment shows that our proposed method significantly reduces the number of actions in the RL environments originating from AI planning domains. Harsha Kokel, Junkyu Lee 0001, Michael Katz 0001, Shirin Sohrabi, Kavitha Srinivas |
AAAI | 1 |
| 2022 | Hybrid Deep RePReL: Integrating Relational Planning and Reinforcement Learning for Information Fusion
Harsha Kokel, Nikhilesh Prabhakar, Balaraman Ravindran, Erik Blasch, Prasad Tadepalli, Sriraam Natarajan |
FUSION | 1 |
| 2022 | ORIENT: Submodular Mutual Information Measures for Data Subset Selection under Distribution ShiftabstractReal-world machine-learning applications require robust models that generalize well to distribution shift settings, which is typical in real-world situations. Domain adaptation techniques aim to address this issue of distribution shift by minimizing the disparities between domains to ensure that the model trained on the source domain performs well on the target domain. Nevertheless, the existing domain adaptation methods are computationally very expensive. In this work, we aim to improve the efficiency of existing supervised domain adaptation (SDA) methods by using a subset of source data that is similar to target data for faster model training. Specifically, we propose ORIENT, a subset selection framework that uses the submodular mutual information (SMI) functions to select a source data subset similar to the target data for faster training. Additionally, we demonstrate how existing robust subset selection strategies, such as GLISTER, GRADMATCH, and CRAIG, when used with a held-out query set, fit within our proposed framework and demonstrate the connections with them. Finally, we empirically demonstrate that SDA approaches like d-SNE, CCSA, and standard Cross-entropy training, when employed together with ORIENT, achieve a) faster training and b) better performance on the target data. Athresh Karanam, KrishnaTeja Killamsetty, Harsha Kokel, Rishabh Iyer 0001 |
NeurIPS | 3 |
| 2021 | A Probabilistic Approach to Extract Qualitative Knowledge for Early Prediction of Gestational Diabetes
Athresh Karanam, Alexander L. Hayes, Harsha Kokel, David M. Haas, Predrag Radivojac, Sriraam Natarajan |
AIME | 3 |
| 2020 | A Unified Framework for Knowledge Intensive Gradient Boosting: Leveraging Human Experts for Noisy Sparse DomainsabstractIncorporating richer human inputs including qualitative constraints such as monotonic and synergistic influences has long been adapted inside AI. Inspired by this, we consider the problem of using such influence statements in the successful gradient-boosting framework. We develop a unified framework for both classification and regression settings that can both effectively and efficiently incorporate such constraints to accelerate learning to a better model. Our results in a large number of standard domains and two particularly novel real-world domains demonstrate the superiority of using domain knowledge rather than treating the human as a mere labeler. Harsha Kokel, Phillip Odom, Shuo Yang 0004, Sriraam Natarajan |
AAAI | 1 |