Flash-Searcher: Fast and Effective Web Agents via DAG-Based Parallel Execution

ICLR 2026 Conference SubmissionAnonymous Authors
Workflow OptimizationAgent ReasoningWebAgentDeep Research
Abstract:

Large language models (LLMs) have demonstrated remarkable capabilities in complex reasoning tasks when equipped with external tools. However, current frameworks predominantly rely on sequential processing, leading to inefficient execution particularly for tasks requiring extensive tool interaction. This paper introduces Flash-Searcher, a novel parallel agent reasoning framework that fundamentally reimagines the execution paradigm from sequential chains to directed acyclic graphs (DAGs). Flash-Searcher decomposes complex tasks into subtasks with explicit dependencies, enabling concurrent execution of independent reasoning paths while maintaining logical constraints. Through dynamic workflow optimization, our framework continuously refines the execution graph based on intermediate results, effectively integrating summary module. Comprehensive evaluations across multiple benchmarks demonstrate that Flash-Searcher consistently outperforms existing approaches. Specifically, it achieves 67.7% accuracy on BrowseComp and 83% on xbench-DeepSearch, while reducing agent execution steps by up to 35% compared to current frameworks. Furthermore, when distilling this parallel reasoning pipeline into single models, we observe substantial performance gains across diverse backbone architectures, underscoring the generalizability of our methodology. Our work thus represents a significant advance in agent architecture design, offering a more scalable and efficient paradigm for complex reasoning tasks.

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This report is AI-GENERATED using Large Language Models and WisPaper (A scholar search engine). It analyzes academic papers' tasks and contributions against retrieved prior work. While this system identifies POTENTIAL overlaps and novel directions, ITS COVERAGE IS NOT EXHAUSTIVE AND JUDGMENTS ARE APPROXIMATE. These results are intended to assist human reviewers and SHOULD NOT be relied upon as a definitive verdict on novelty.
NOTE that some papers exist in multiple, slightly different versions (e.g., with different titles or URLs). The system may retrieve several versions of the same underlying work. The current automated pipeline does not reliably align or distinguish these cases, so human reviewers will need to disambiguate them manually.
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Overview

Overall Novelty Assessment

Flash-Searcher introduces a parallel agent reasoning framework that decomposes complex tasks into DAG-structured subtasks for concurrent execution. The paper positions itself within the 'Native Parallel Reasoning Capabilities in LLMs' leaf, which contains only two papers including the original work. This represents a relatively sparse research direction within the broader taxonomy of fifty papers, suggesting the specific focus on intrinsic parallel reasoning abilities in LLMs remains underexplored compared to external orchestration approaches.

The taxonomy reveals that Flash-Searcher sits at the intersection of multiple research threads. Its immediate parent branch 'Parallel Reasoning and Planning in LLM Agents' encompasses plan-then-execute architectures and graph-enhanced reasoning methods, while sibling branches address multi-agent coordination networks and dynamic task graph generation. The framework diverges from these neighboring areas by embedding parallelism within the model's reasoning process rather than relying on external DAG schedulers or multi-agent collaboration networks, as clarified by the leaf's exclude_note distinguishing native capabilities from orchestration systems.

Among thirty candidates examined across three contributions, no clearly refutable prior work was identified. The core FLASH-SEARCHER framework examined ten candidates with zero refutations, as did the parallel reasoning trajectories contribution and the open-source pipeline contribution. This absence of overlapping prior work within the limited search scope suggests the specific combination of DAG-based parallel execution with agent reasoning for search tasks may represent a novel configuration, though the analysis acknowledges this reflects top-K semantic matches rather than exhaustive coverage of the literature.

Based on the limited search scope of thirty semantically similar papers, Flash-Searcher appears to occupy a distinct position within a sparse research direction. The taxonomy structure indicates that while DAG-based coordination and parallel reasoning are established themes across multiple branches, the specific approach of native parallel reasoning capabilities in LLMs remains less populated. The contribution-level statistics provide no evidence of substantial prior overlap within the examined candidates, though broader literature may contain relevant work outside the semantic search radius.

Taxonomy

Core-task Taxonomy Papers
50
3
Claimed Contributions
30
Contribution Candidate Papers Compared
0
Refutable Paper

Research Landscape Overview

Core task: parallel agent reasoning via directed acyclic graph execution. The field organizes around several major branches that reflect different emphases on how DAG structures enable concurrent computation and coordination. DAG-Based Multi-Agent Coordination and Task Orchestration focuses on workflow decomposition and inter-agent dependencies, with works like AI-Native Orchestration[7] and HiveMind[6] exploring how to schedule and synchronize multiple agents. Parallel Reasoning and Planning in LLM Agents examines how large language models can natively exploit DAG representations to perform concurrent inference steps, as seen in Native Parallel Reasoner[1] and Dag Plan[2]. Retrieval-Augmented Generation with DAG-Based Reasoning investigates structured retrieval pipelines that use graph topologies to guide information flow, while Distributed Inference and Computation with DAG Models addresses the lower-level challenge of partitioning neural network computations across devices. Multi-Agent Reinforcement Learning with Graph-Based Coordination and Domain-Specific Applications branches capture learning-driven coordination and specialized use cases, respectively, and Theoretical Foundations and Formal Methods provide rigorous underpinnings for correctness and efficiency. A particularly active line of work centers on native parallel reasoning capabilities within LLMs, where the goal is to enable models to decompose complex queries into concurrent subproblems without external orchestration layers. Flash Searcher[0] sits squarely in this cluster, emphasizing how DAG execution can accelerate search-like reasoning tasks by exploiting inherent parallelism in the problem structure. This contrasts with approaches like Resilient LLM Agents[3], which prioritize robustness and fault tolerance in multi-step workflows, and Multi-Step Search[4], which focuses on sequential refinement rather than concurrent exploration. Meanwhile, works such as Scaling Multi-Agent[5] and DynTaskMAS[11] tackle the orchestration challenge from a coordination perspective, managing dependencies among heterogeneous agents rather than parallelizing a single model's reasoning. The interplay between these directions highlights an open question: whether parallelism should be baked into the reasoning model itself or managed by an external DAG scheduler, with Flash Searcher[0] advocating for the former to minimize coordination overhead.

Claimed Contributions

FLASH-SEARCHER parallel agent reasoning framework

The authors propose a new framework that decomposes complex tasks into subtasks with explicit dependencies, enabling concurrent execution of independent reasoning paths while maintaining logical constraints through DAG-based planning and dynamic workflow optimization.

10 retrieved papers
High-quality parallel reasoning trajectories for model post-training

The authors construct a dataset of DAG-based reasoning trajectories from multiple sources and demonstrate that lightweight supervised fine-tuning on this data effectively transfers parallel reasoning capabilities to open-source models, achieving substantial performance improvements.

10 retrieved papers
Open-source pipeline and datasets

The authors commit to releasing their complete framework implementation, training datasets, and evaluation code to enable reproducibility and facilitate further research in parallel agent reasoning systems.

10 retrieved papers

Core Task Comparisons

Comparisons with papers in the same taxonomy category

Contribution Analysis

Detailed comparisons for each claimed contribution

Contribution

FLASH-SEARCHER parallel agent reasoning framework

The authors propose a new framework that decomposes complex tasks into subtasks with explicit dependencies, enabling concurrent execution of independent reasoning paths while maintaining logical constraints through DAG-based planning and dynamic workflow optimization.

Contribution

High-quality parallel reasoning trajectories for model post-training

The authors construct a dataset of DAG-based reasoning trajectories from multiple sources and demonstrate that lightweight supervised fine-tuning on this data effectively transfers parallel reasoning capabilities to open-source models, achieving substantial performance improvements.

Contribution

Open-source pipeline and datasets

The authors commit to releasing their complete framework implementation, training datasets, and evaluation code to enable reproducibility and facilitate further research in parallel agent reasoning systems.