Bridging Physical Reasoning and Task Generalization via Visual Action Outcome Reasoning Alignment

Anonymous Author(s)
Affiliation withheld for double-blind review
NeurIPS 2026 (Under Review)
VAORA teaser: two failure modes in CoT-based physical reasoning

Two major obstacles in CoT-based physical reasoning. Hallucinated CoT denotes the model producing physically incorrect reasoning that leads to a wrong action; Misaligned Action bypasses physically-aligned reasoning via a visual shortcut, resulting in wrong action planning. Our VAORA resolves both, generating a successful action with proper physical reasoning.

Abstract

Vision-language models (VLMs) struggle to generalize in interactive physical reasoning, particularly under unseen tasks and environments. Two key failure modes are prominent: hallucinated chain-of-thought (CoT) reasoning that contradicts physical reality, and misalignment between the model's reasoning and actions. We present VAORA (Visual Action Outcome Reasoning Alignment), a novel reward design that directly addresses both issues. VAORA introduces two complementary rewards: a Visual Alignment Reward, which anchors VLM reasoning to the visual context independent of the agent action itself, and a Visual-Action Alignment Reward, which grounds reasoning in the visual outcome induced by the model's action. Together, these rewards suppress hallucinated CoT and reduce the gap between reasoning and behavior. To improve training stability, we further employ smooth, dense rewards by estimating success probabilities using a pre-trained in-domain expert agent. Experiments on PHYRE and Virtual Tool support our performance across novel-task and unseen-environment settings, confirming that grounded and generalizable physical intelligence can be induced through VAORA.

VAORA Logo VAORA Method

Overview

True physical agents must go beyond memorizing scene configurations and instead reason about spatial relationships, dynamics, and causality to act in novel situations. We characterize this through two forms of generalization: cross-task transfer within the same environment, and cross-environment transfer across distinct physics simulators. Conventional non-VLM agents (e.g., DQN) collapse perception and decision-making into a single opaque mapping, learning spurious visual-to-action correlations that fail to transfer. Vision-language models offer a different paradigm by replacing reactive mappings with explicit causal reasoning, yet the two dominant training paradigms — Supervised Fine-Tuning (SFT) and success-driven RL — each introduce structural limitations.

We identify that both SFT and success-driven RL fail to supervise the connection between CoT reasoning and physical reality, leading to two failure modes: hallucinated CoT that contradicts physical reality, and reasoning-action misalignment where the model takes a visual shortcut that bypasses its own stated reasoning. VAORA resolves both by requiring the reasoning trace to remain consistent with the visual observations of the environment — both the initial scene and the post-interaction outcome — within a shared symbolic space.

Framework

VAORA framework

Framework. VAORA consists of two components: (a) Visual-Alignment Reward, which anchors reasoning to action-independent visual context (the grounding reward rG). (b) Gated Visual-Action Alignment Reward, which aligns reasoning with the visual outcome of the model's action (the collision reward rC and placement reward rP), gated by a success probability estimated by a pre-trained DQN expert. The reasoning chain, initial scene observation, and post-interaction outcome are projected into a shared symbolic space where their consistency is measured.

Reward Design

Visual Alignment Reward. To anchor the reasoning trace to a scene independent of the model's action, the grounding reward rG aligns the VLM's perception of the initial scene configuration with the real initial observation. A model that cannot accurately perceive the scene before acting will inevitably produce reasoning inconsistent with physical reality, so this reward directly attacks hallucinated CoT at its source.

Visual-Action Alignment Reward. Two rewards ground the reasoning trace in the physical consequences of the action. The collision reward rC aligns the model's predicted collision events with the post-interaction outcome, while the placement reward rP aligns the predicted ball placement with its actual position in the first post-interaction frame — together addressing reasoning-action misalignment.

Expert-Guided (EG) Optimization. Sparse binary task-success rewards in continuous action spaces often cause policy collapse. We replace the binary success signal with a smooth, dense success probability estimated by a pre-trained DQN expert, rDQN. The visual-action alignment rewards are gated by rDQN so that reasoning quality is rewarded only when the action is physically plausible, while rG is optimized outside the gate. The two components are jointly optimized with GDPO.

Experiment Results

Generalization Settings

VAORA generalization settings

Generalization of VAORA. We train VAORA on PHYRE tasks and evaluate across three scenarios: (a) the PHYRE test set for cross-task generalization, (b) Virtual Tool for cross-engine (cross-environment) generalization, and (c) CRAFT VQA to assess the transferability of learned reasoning to visual question answering.

Results

VAORA substantially outperforms open-source VLMs and the majority of closed-source API baselines, and surpasses the in-domain DQN expert on most metrics — demonstrating that properly aligned reasoning confers a genuine generalization advantage over direct visual-to-action mapping agents. The full model (+EG+VAORA) is highlighted.

Pass@k on PHYRE test sets across three held-out task splits. VAORA outperforms all VLM baselines and surpasses the in-domain DQN expert on most metrics (bold = our full model).

Models Testing Set 1 Testing Set 2 Testing Set 3
Pass@1Pass@3Pass@5 Pass@1Pass@3Pass@5 Pass@1Pass@3Pass@5
Human0.5200.7580.8000.4720.8220.9200.5200.7320.820
DQN-expert0.3260.4340.4760.2600.3680.4180.3380.4120.466
InternVL-3.5-8B0.0440.0940.1340.0280.0840.1300.0500.1040.154
Qwen3VL-8B0.0020.0080.2000.0180.0440.0780.0160.0400.074
Qwen3VL-8B (SFT)0.1760.3800.4700.1460.3440.4520.1760.3680.452
Qwen3VL-8B (GRPO)0.0060.0400.0620.0160.0380.0560.0240.0600.108
Qwen3VL-8B (SFT+GRPO)0.0200.0260.0300.0420.1240.1720.0220.0780.102
Claude-Sonnet-4.60.0420.1040.1420.0360.0880.1220.0300.0740.108
GPT-5.40.0640.1320.1860.0480.0960.1440.0440.0860.140
Gemini-3.1-Pro0.2780.4720.5520.2200.3680.4200.2780.4840.554
Gemini-3.1-Flash0.1700.3400.4160.1920.3020.3520.1420.2940.376
Ours: +EG (Expert-Guided)0.2700.4360.5120.1780.3120.3620.2180.3400.392
Ours: +EG+VAORA0.3820.5240.5940.1980.3900.4720.3000.4560.512

BibTeX

@inproceedings{anonymous2026vaora,
        title={Bridging Physical Reasoning and Task Generalization via Visual Action Outcome Reasoning Alignment},
        author={Anonymous Author(s)},
        booktitle={Advances in Neural Information Processing Systems (NeurIPS)},
        note={Under double-blind review},
        year={2026}
      }