ECCV 2026

Agentic Collaborative Cognition

for Zero-Shot 3D Understanding

1Sichuan University 2Adelaide University 3University of Electronic Science and Technology of China 4Beijing Institute of Technology
*Equal contribution Project lead Corresponding author

Collaborative Planning and Perception for 3D Scenes

Comparison between existing zero-shot 3D understanding methods and the proposed collaborative planning and perception framework.
Figure 1. Existing zero-shot 3D understanding methods rely on finite viewpoints, while the proposed framework actively plans query-relevant views and integrates observations through collaborative agents.
Abstract

Agentic Zero-Shot 3D Understanding

Recent advancements have explored agentic zero-shot 3D understanding by reformulating it as video keyframe understanding with Multimodal Large Language Models (MLLMs). However, existing methods face an intrinsic bottleneck due to the finite observation perspectives inherent in videos and the implicit perception of 3D scenes. In this paper, we propose a collaborative multi-agent framework that assigns a Planning Agent to handle high-level viewpoint planning and supplement novel perspectives, and a Perception Agent to explicitly summarize the 3D scene into a structured holistic cognitive map. Specifically, Planning Agent first analyzes this cognitive map to determine query-relevant viewpoints and supplements missing critical perspectives to ensure comprehensive observation. Subsequently, Perception Agent documents object-level attributes from these views by assigning consistent instance identifiers across viewpoints, thereby integrating fragmented observations into the holistic cognitive map. In parallel, it provides feedback to filter out mismatched candidate objects and guide subsequent viewpoint planning. Through this closed-loop iterative process, two agents collaboratively figure out candidates until Perception Agent determines that sufficient information has been captured to complete the task. Extensive experiments demonstrate that our method achieves state-of-the-art performance on 6 benchmarks, with improvements of 11.1% Acc@0.5 on ScanRefer, 14.6 BLEU-1 on 3D-assisted dialog, and 2.1 EM on SQA3D.

Method

Collaborative Multi-Agent Framework

Overview of the proposed Planning Agent and Perception Agent collaboration framework.
Figure 2. The Planning Agent selects informative viewpoints, while the Perception Agent consolidates object-level evidence and returns feedback for subsequent planning and final reasoning.
Experiments

Results

3D Visual Grounding

ScanRefer Acc@0.5
+11.1

3D Question Answering

SQA3D EM
+2.1

3D-Assisted Dialog

Dialog BLEU-1
+14.6

3D Visual Grounding

Setting Method ScanRefer Acc@0.25 ScanRefer Acc@0.5 Nr3D Acc@0.25
Zero-shot, 250 queries
250 queries VLM-Grounder 51.6 32.8 48.0
250 queries SeqVLM 55.6 49.6 53.2
250 queries SPAZER 57.2 48.8 63.8
250 queries Ours 58.0 50.0 65.6
Zero-shot, full validation set
Full ZSVG3D 36.4 32.7 39.0
Full SeeGround 44.1 39.4 46.1
Full CSVG 49.6 39.8 59.2
Full Ours 58.1 50.9 61.2

The full-set comparison tests whether active viewpoint planning transfers beyond the 250-query protocol. Ours raises ScanRefer Overall Acc@0.5 from 39.8 to 50.9 while also improving Nr3D Overall Acc@0.25 from 59.2 to 61.2.

3D Question Answering

Method SQA3D Overall ScanQA CIDEr ScanQA BLEU-4 ScanQA METEOR ScanQA ROUGE ScanQA EM
Agent3D-Zero - 71.8 4.4 16.0 37.0 17.5
SpatialPrompting 52.7 87.7 10.9 16.9 43.4 27.3
Ours 54.8 91.1 12.3 17.4 44.5 28.7

SpatialPrompting already uses object-centric visual prompts; Ours adds explicit scene cognition, improving SQA3D Overall from 52.7 to 54.8 and ScanQA CIDEr from 87.7 to 91.1.

3D-Assisted Dialog

Method 3D-assisted Dialog Task Decomposition
B-1 B-4 M R B-1 B-4 M R
3D-LLM 39.0 16.6 18.9 39.3 33.9 7.4 15.9 37.8
Agent3D-Zero 32.8 9.8 19.3 39.3 42.0 15.5 22.9 45.1
Ours 47.4 24.0 28.6 47.3 43.8 24.9 21.0 48.8

On held-in 3D dialog, Ours surpasses Agent3D-Zero without task-specific supervision, lifting dialog B-1 from 32.8 to 47.4 and B-4 from 9.8 to 24.0.

Qualitative 3D visual grounding example. Qualitative situated understanding example. Qualitative visual question answering example.
Qualitative Results. The examples show spatial grounding among repeated objects, egocentric situation understanding, and scene-layout question answering.
Citation

BibTeX