WorldCast is a benchmark for world state prediction in visual generation: given observations and diverse references, a model must generate the sequence of future states that a process goes through, not just a plausible final image. Such a task is demanding for unified systems, multi-reference image models, and video models alike, because it requires understanding and generation to work together: the model has to work out what each reference means, when it takes effect, and how the world changes as a result. We offer both a benchmark of 320 manually designed cases and a common evaluation protocol that scores grid, interleaved, and video outputs as one ordered sequence of states, together with a diagnosis of 12 representative models.
2026.10.12Released the WorldCast dataset, evaluation toolkit, and Judge rubrics.
Higher-level generative capabilities are underexplored. We organize visual generation into a four-level capability tree. L1 is static text-to-image generation. L2 adds pixel-level control and temporal transition, such as editing, subject reference, and text- or image-to-video. L3 requires modelling complex constraints and simulating complex causality, with multiple references, world knowledge, and physical plausibility. L4 requires transforming real-world context into action: implicit visual intents, spatial cues, visual goals, demonstrated procedures, and logical patterns. Frontier models have moved quickly through L1 and L2, yet L3 and L4, where understanding and generation must be tightly integrated, are rarely measured.
Real-world processes are dynamic, and references do more than fix appearance. Prior work mostly asks whether a model can simulate the world from a static appearance anchor such as a first frame or a subject image. In real tasks, references intervene at different points of a process. A reference may be a state to observe, a goal to reach, a rule to obey, a material property, or a demonstration of how something is done. We call this world state prediction: using heterogeneous context to guide an evolving real-world process. The model must reason about each reference before it can draw the next state.
One protocol for image and video models. Whether a model produces a grid, interleaved text and images, or a continuous video, its success must show up in the resulting visual states. WorldCast therefore evaluates every output as an ordered sequence of key frames, and each case carries human-annotated HINTS that tell the GPT-5.5 Judge what a correct sequence must show.
What we find from this benchmark:
- Frontier unified systems show early-stage world state prediction. GPT-Image-2.5 scores 72.8 and handles some L3 and even L4 tasks, with emerging generalization across categories.
- The gaps between models are large and widen at higher levels. Nano Banana Pro reaches 42.8 and the best open-source model 20.1. Complex context, entangled references, and reasoning-heavy tasks are the common failure points.
- Interleaved generation helps image models. Generating one state at a time with a text plan lets frontier image models capture critical temporal transitions without a video architecture.
- Strong generators draw on their language models. Performance gaps track language-side planning and reasoning. Adding agentic abilities such as inspection-and-revision loops and coding tools brings further gains and exposes new challenges.
WorldCast has 320 manually designed cases requesting 1,352 visual states across eight task categories. Every case comes with human-annotated HINTS that tell the Judge what a correct sequence must show.
| Model | Type | Format | L3 | L4 | Overall |
|---|---|---|---|---|---|
| GPT-Image-2.5 | Proprietary image | Interleaved | 73.8 | 71.6 | 72.8 |
| GPT-Image-2 | Proprietary image | Interleaved | 68.3 | 63.7 | 66.2 |
| Seedance 2.0 | Video | Video | 51.9 | 41.6 | 47.2 |
| Nano Banana Pro | Proprietary image | Interleaved | 45.6 | 39.5 | 42.8 |
| Gemini Omni | Video | Video | 45.8 | 36.8 | 41.6 |
| Wan 3.0 | Video | Video | 46.0 | 32.8 | 39.9 |
| Seedream 5.0 Pro | Proprietary image | Grid | 36.8 | 29.9 | 33.6 |
| SenseNova-U1 | Open-source image | Interleaved | 24.4 | 15.0 | 20.1 |
| Seedream 4.5 | Proprietary image | Grid | 17.6 | 14.1 | 16.0 |
| Emu3.5 | Open-source image | Interleaved | 16.5 | 7.4 | 12.3 |
| BAGEL | Open-source image | Plan & iterate | 6.7 | 6.8 | 6.8 |
| Qwen-Image | Open-source image | Grid | 6.9 | 4.0 | 5.6 |
Scores are on a 0β100 scale. GPT-Image-2.5 is paired with GPT-6 Astra, and GPT-Image-2 with GPT-5.5.
The benchmark is hosted on Hugging Face at wenhaoyan77/WorldCast.
from datasets import load_dataset
dataset = load_dataset("wenhaoyan77/WorldCast", split="test")Each case provides the text prompt, the ordered initial_images, the number of
requested steps, the target_grid layout for grid models, and the Judge-only hints_by_metric and hint_images. See the
dataset card for all fields.
Requires Python 3.10+.
git clone https://github.com/teal024/WorldCast.git
cd WorldCast
pip install -e .The Judge is GPT-5.5 with medium reasoning effort, called through the OpenAI
Responses API. Set OPENAI_API_KEY before running an evaluation.
worldcast download data/This writes one folder per case:
data/
βββ <case_id>/
βββ case.json # prompt, steps, category, HINTS
βββ reference_01.png # input images, in prompt order
βββ hint_01.png # Judge-only reference (few cases)
Give your model each case's prompt and initial_images, and save the generated
states in order. Do not give the model the HINTS or hint images.
outputs/<model>/
βββ <case_id>/
βββ 1.png
βββ 2.png
βββ ...
Images are ordered by filename. The prompt wrappers used for each generation
format are in worldcast.adapters and shown in
docs/prompts.html.
Grid models. A model that draws all steps in one image is scored on the
individual cells. Put the grids in grids/<model>/<case_id>.png and run:
worldcast split-grids data/ grids/<model> outputs/<model>The grid is cut into equal cells in reading order, following each case's
target_grid: 1x2 for 2 steps, 2x2 for 4 steps and 2x3 for 6 steps.
Video models. A video has to be converted into an ordered set of key frames
before it can be scored. In the paper this is done by an Agentic Video
Adapter: GPT-6 Astra at medium reasoning effort, run as an agent through
Codex, inspects the video and
selects the frames that cover as many of the requested states as possible while
keeping their temporal order. The adapter only decides which frames show the
required states. It does not judge the quality or plausibility of the video.
Put the videos in videos/<model>/<case_id>.mp4 and run:
worldcast extract-frames data/ videos/<model> outputs/<model> --workers 4This needs ffmpeg and an authenticated Codex CLI.
The frames are written to outputs/<model>/<case_id>/, ready for Step 3. The
prompt template is in docs/prompts.html.
To try the video pipeline on a small synthetic example:
python examples/make_video_example.py outputs/video-demo
worldcast extract-frames outputs/video-demo/data outputs/video-demo/videos outputs/video-demo/frames
worldcast run outputs/video-demo/data outputs/video-demo/frames --results outputs/video-demo/resultsworldcast run data/ outputs/<model> --results results/<model> --workers 4This calls the Judge and consumes model quota. Each case's scores are written to
results/<model>/<case_id>.json. Completed judgments are cached in checkpoints/,
so an interrupted run can simply be started again. Use --cases 519 520 to
evaluate a subset.
worldcast summarize results/<model>This prints the score per category, per level, and overall.
To inspect the exact Judge requests for a single case without calling any model:
python examples/make_example.py outputs/demo
worldcast evaluate outputs/demo/case.json --dry-run| Component | Score | Generated images shown to the Judge |
|---|---|---|
| Progress Alignment (PA) | 0β2 | Full sequence |
| Outcome Completion (OC) | 0/1 | Final image only |
| Causal Plausibility (CP) | 0β3 | Full sequence |
| Visual Consistency (VC) | 0β3 | Full sequence |
Task Completion combines PA and OC with the case's outcome weight
w = result_weight / 100. Process-focused cases have w = 0 and skip OC.
TC = 1.5 Γ ((1 β w) Γ PA + 2 Γ w Γ OC)
Overall = (TC + CP + 0.5 Γ VC) / 7.5 Γ 100
Step Accuracy (SA) is an optional per-step analysis for interleaved models and does not enter the overall score. The full rubrics are in docs/rubrics.html, and the input format and scoring details are in the evaluation guide.
WorldCast/
βββ src/worldcast/ # Evaluation toolkit and CLI
β βββ resources/ # Judge rubrics used by the evaluator
βββ scripts/ # Dataset build and upload, rubric rendering
βββ docs/ # Evaluation guide, dataset card, rubrics, prompt templates
βββ examples/ # Synthetic image and video cases for a trial run
βββ tests/ # Offline tests, no model calls
@misc{yan2026worldcast,
title={WorldCast: Exploring Intelligent Visual Generation in World State Prediction},
author={Yan, Wenhao and Li, Haodong and Li, Xiaotong and Luo, Yaxin and Yue, Zhengrong and Zou, Jialv and Huang, Xu and Yang, Haojin and Jia, Nan and Feng, Yan and Pei, Peng and Cai, Xunliang},
year={2026},
eprint={2610.20731},
archivePrefix={arXiv},
url={https://arxiv.org/abs/2610.20731}
}The code is released under the MIT License. The dataset is released under CC BY 4.0.

