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arxiv: 1906.08291 · v1 · pith:HWFERYR3new · submitted 2019-06-19 · 💻 cs.AI · cs.MA· cs.RO

Multi-Agent Pathfinding: Definitions, Variants, and Benchmarks

Roni Stern , Nathan Sturtevant , Ariel Felner , Sven Koenig , Hang Ma , Thayne Walker , Jiaoyang Li , Dor Atzmon
show 4 more authors
Liron Cohen T. K. Satish Kumar Eli Boyarski Roman Bartak
This is my paper

Pith reviewed 2026-05-25 20:12 UTC · model grok-4.3

classification 💻 cs.AI cs.MAcs.RO
keywords multi-agent pathfindingMAPFbenchmarksassumptionsobjectivesvariantsgrid benchmarkcollision rules
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The pith

A unifying terminology for multi-agent pathfinding assumptions and objectives enables consistent comparisons and helps match papers to applications.

A machine-rendered reading of the paper's core claim, the machinery that carries it, and where it could break.

The paper establishes a shared set of terms to describe varying assumptions and objective functions across multi-agent pathfinding research. Different papers have used inconsistent rules, such as whether agents may occupy the same space at once, and different success measures, such as minimizing the completion time of the last agent or the total movement cost. These inconsistencies have made fair algorithm comparisons difficult and have hindered practitioners from locating suitable methods for uses like warehouse automation or vehicle coordination. The work supplies clear definitions for common variants along with references to existing benchmarks and introduces a new grid-based benchmark shown to challenge current solvers.

Core claim

By supplying a unifying terminology for describing common MAPF assumptions and objectives, together with pointers to two benchmarks and the introduction of a new grid-based benchmark that contemporary algorithms find challenging, the paper supports researchers in establishing appropriate baselines and helps practitioners identify relevant work for concrete applications.

What carries the argument

The unifying terminology for MAPF assumptions (collision rules) and objectives (makespan versus sum-of-costs).

If this is right

  • Researchers can establish appropriate baselines for comparison more easily.
  • Practitioners can more readily locate papers relevant to specific applications.
  • The new grid-based benchmark serves as a standard test that stresses current algorithms.
  • MAPF studies can proceed with less ambiguity in problem statements.

Where Pith is reading between the lines

These are editorial extensions of the paper, not claims the author makes directly.

  • Algorithms might be designed with explicit parameters that switch between the defined variants.
  • Real-world constraints from autonomous systems could be mapped onto the terminology to surface under-studied cases.
  • Future benchmark collections could incorporate dynamic or uncertain elements while remaining consistent with the defined terms.

Load-bearing premise

The proposed terminology captures the most important distinctions used in the literature and will be adopted by the community.

What would settle it

A later survey of MAPF papers that finds most still describe their problem settings with ad-hoc language and without reference to the proposed terms.

Figures

Figures reproduced from arXiv: 1906.08291 by Ariel Felner, Dor Atzmon, Eli Boyarski, Hang Ma, Jiaoyang Li, Liron Cohen, Nathan Sturtevant, Roman Bartak, Roni Stern, Sven Koenig, Thayne Walker, T. K. Satish Kumar.

Figure 1
Figure 1. Figure 1: An illustration of common types of conflicts. From left [PITH_FULL_IMAGE:figures/full_fig_p002_1.png] view at source ↗
Figure 2
Figure 2. Figure 2: 2 k Neighborhood movement models for k = 2,3,4 and 5. 3.1 MAPF on Weighted Graphs The assumption that each action – move or wait – takes exactly one time step, implicitly assumes a somewhat sim￾plistic motion model for the agents. More complex motion models have been studied in the MAPF literature, in which different actions may have different duration. This means the underlying graph that represents the p… view at source ↗
Figure 3
Figure 3. Figure 3: An example of a designated method for setting sources [PITH_FULL_IMAGE:figures/full_fig_p005_3.png] view at source ↗
Figure 4
Figure 4. Figure 4: Illustration of a warehouse grid (Cohen et al. 2018b). [PITH_FULL_IMAGE:figures/full_fig_p005_4.png] view at source ↗
Figure 5
Figure 5. Figure 5: An example of a map from each type of maps available [PITH_FULL_IMAGE:figures/full_fig_p005_5.png] view at source ↗
Figure 6
Figure 6. Figure 6: Two scenarios from the Asprilo framework. The left fig [PITH_FULL_IMAGE:figures/full_fig_p006_6.png] view at source ↗
read the original abstract

The MAPF problem is the fundamental problem of planning paths for multiple agents, where the key constraint is that the agents will be able to follow these paths concurrently without colliding with each other. Applications of MAPF include automated warehouses and autonomous vehicles. Research on MAPF has been flourishing in the past couple of years. Different MAPF research papers make different assumptions, e.g., whether agents can traverse the same road at the same time, and have different objective functions, e.g., minimize makespan or sum of agents' actions costs. These assumptions and objectives are sometimes implicitly assumed or described informally. This makes it difficult to establish appropriate baselines for comparison in research papers, as well as making it difficult for practitioners to find the papers relevant to their concrete application. This paper aims to fill this gap and support researchers and practitioners by providing a unifying terminology for describing common MAPF assumptions and objectives. In addition, we also provide pointers to two MAPF benchmarks. In particular, we introduce a new grid-based benchmark for MAPF, and demonstrate experimentally that it poses a challenge to contemporary MAPF algorithms.

Editorial analysis

A structured set of objections, weighed in public.

Desk editor's note, referee report, simulated authors' rebuttal, and a circularity audit. Tearing a paper down is the easy half of reading it; the pith above is the substance, this is the friction.

Referee Report

0 major / 2 minor

Summary. The paper proposes a unifying terminology for common assumptions (e.g., collision rules, movement timing) and objective functions (e.g., makespan vs. sum-of-costs) in the multi-agent pathfinding (MAPF) problem. It supplies explicit definitions, pointers to two existing benchmarks, introduces a new grid-based benchmark instance set, and reports experiments showing that the new benchmark challenges contemporary MAPF solvers.

Significance. If the terminology is adopted, the paper would improve the ability to establish fair baselines across MAPF papers and help practitioners locate relevant work. The new benchmark and its experimental demonstration constitute a concrete, falsifiable contribution that can be directly reused by the community.

minor comments (2)
  1. The abstract states that pointers are provided to 'two MAPF benchmarks' but does not name them in the provided text; the full manuscript should list the specific repositories or papers in §1 or a dedicated benchmarks section.
  2. The experimental section should include the precise instance counts, grid sizes, and agent densities used in the new benchmark so that the claim 'it poses a challenge' can be reproduced without ambiguity.

Simulated Author's Rebuttal

0 responses · 0 unresolved

We thank the referee for their positive assessment of the manuscript, including its potential to improve baselines and reusability of the new benchmark, and for the recommendation to accept.

Circularity Check

0 steps flagged

No significant circularity

full rationale

The paper proposes unifying terminology for MAPF variants and introduces a new benchmark with experimental results showing it challenges solvers. It contains no derivations, equations, predictions, or fitted parameters. The central claims are definitional and empirical (terminology aids comparison; benchmark is hard), with no reduction to self-defined quantities or self-citation chains. External pointers and direct experiments provide independent support.

Axiom & Free-Parameter Ledger

0 free parameters · 0 axioms · 0 invented entities

This is a survey and standardization paper; it introduces no mathematical derivations, fitted parameters, or new physical entities. The contribution rests on the assumption that existing MAPF literature contains identifiable common variants that can be usefully named.

pith-pipeline@v0.9.0 · 5763 in / 1063 out tokens · 34594 ms · 2026-05-25T20:12:52.413217+00:00 · methodology

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Citations machine-checked in the Pith Canon. Every link opens the source theorem in the public Lean library.

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matches
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supports
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extends
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uses
The paper appears to rely on the theorem as machinery.
contradicts
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unclear
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Forward citations

Cited by 1 Pith paper

Reviewed papers in the Pith corpus that reference this work. Sorted by Pith novelty score.

  1. Generating Local Shields for Decentralised Partially Observable Markov Decision Processes

    cs.MA 2026-04 unverdicted novelty 7.0

    A process algebra with guarded choice and recursion is compiled to global and then projected local Mealy machines that filter safe joint actions for each agent in Dec-POMDPs using belief-style state subsets.

Reference graph

Works this paper leans on

30 extracted references · 30 canonical work pages · cited by 1 Pith paper · 1 internal anchor

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