---
title: WebSTAR
canonical_url: "https://www.modelscope.cn/datasets/microsoft/WebSTAR"
md_url: "https://www.modelscope.cn/datasets/microsoft/WebSTAR.md"
repository: microsoft/WebSTAR
last_updated: 2026-02-11
license: cdla-permissive-2.0
storage_size: "59 GB"
downloads: 8374
stars: 0
---

# WebSTAR

> WebSTAR - microsoft 在 ModelScope 开源的数据集。WebSTAR: WebVoyager Step-Level Trajectories with Augmented Reasoning

microsoft/WebSTAR 是 ModelScope 魔搭社区上的数据集，存储大小 59 GB，采用 cdla-permissive-2.0 许可。

- **Repository**: microsoft/WebSTAR
- **License**: cdla-permissive-2.0
- **Storage size**: 59 GB
- **Downloads**: 8374
- **Stars**: 0
- **Last updated**: 2026-02-11

Source: https://www.modelscope.cn/datasets/microsoft/WebSTAR

---

# WebSTAR: WebVoyager Step-Level Trajectories with Augmented Reasoning

## Dataset Description

**WebSTAR (WebVoyager Step-Level Trajectories with Augmented Reasoning)** is a large-scale dataset for training and evaluating computer use agents with step-level quality scores. This dataset is part of the research presented in ["Scalable Data Synthesis for Computer Use Agents with Step-Level Filtering"](https://arxiv.org/abs/2512.10962) (He et al., 2025).

Unlike traditional trajectory-level filtering approaches, WebSTAR provides fine-grained step-level scores for each action in an agent's trajectory, enabling more precise quality assessment and selective training on high-quality steps.

NOTE: For the release, we combine the WebSTAR and WebSCORE datasets into a single unified dataset named WebSTAR, which includes the step-level scores and detailed justifications from the judge.

### Key Features

- **Step-level scoring**: Each action in a trajectory is individually scored (1-10 scale)
- **Detailed justifications**: Every score is accompanied by a comprehensive evaluation explaining the reasoning
- **Multi-step reasoning**: Trajectories contain complex, multi-step web navigation tasks

## Dataset Structure

### Data Format

Each example in WebSTAR is structured as follows:

```json
{
    "system": "System prompt with action space definitions and instructions",
    "conversations": [
        {
            "role": "user",
            "content": "<image>Please analyze the attached screenshot and give the Thought and Action."
        },
        {
            "from": "assistant",
            "value": "Thought: ... \nAction: ...",
            "score": 9,
            "judge": "Detailed step-by-step evaluation of the action's quality..."
        },
        ...
    ],
    "images": [
        "screenshots/task_screenshot0.png",
        "screenshots/task_screenshot1.png",
        "screenshots/task_screenshot2.png",
        ...
    ]
}
```

**Note on Images**:
- Each user turn includes an `<image>` tag representing a screenshot of the current state of the web browser/application
- The `images` key contains a list of file paths to all screenshots in the trajectory, ordered sequentially
- The i-th screenshot in the `images` list corresponds to the i-th `<image>` tag in the conversation
- Screenshots are provided as separate PNG files referenced by these paths

### Fields

- **system** (str): System prompt defining the agent's role, available actions, and output format
- **conversations** (list): Alternating user requests and assistant responses
  - **role/from** (str): Speaker identifier ("user" or "assistant")
  - **content/value** (str): Message content
    - **User messages**: Include an `<image>` tag representing the screenshot of the current browser/application state, followed by a request to analyze and respond
    - **Assistant messages**: Include structured "Thought:" and "Action:" explaining reasoning and the chosen action
  - **score** (int, assistant only): Quality score from 1-10 for the proposed action
  - **judge** (str, assistant only): Detailed multi-step evaluation providing justification for the score
- **images** (list of str): Ordered list of file paths to screenshots corresponding to each step in the trajectory. The i-th image corresponds to the i-th `<image>` tag in the conversations.

### Visual Data

Each trajectory is multimodal, combining:
- **Text**: Task descriptions, thoughts, actions, and evaluations
- **Screenshots**: Visual state at each step (indicated by `<image>` tags)

The first user message contains the initial task and starting screenshot. Subsequent user messages contain follow-up screenshots after each action is executed, allowing the agent to observe the results of its actions.

### Action Space

The dataset includes the following action types:
- `click(point='<point>x y</point>')`: Click at coordinates
- `left_double(point='<point>x y</point>')`: Double-click
- `right_single(point='<point>x y</point>')`: Right-click
- `drag(start_point='<point>x1 y1</point>', end_point='<point>x2 y2</point>')`: Drag operation
- `hotkey(key='ctrl c')`: Keyboard shortcuts
- `type(content='xxx')`: Text input
- `scroll(point='<point>x y</point>', direction='down/up/right/left')`: Scrolling
- `wait()`: Wait 5 seconds
- `finished(content='xxx')`: Task completion with answer

## Step-Level Scoring System

Each action is evaluated on a 1-10 scale:

- **9-10**: Optimal action that directly advances the task with no better alternatives
- **7-8**: Correct action that makes meaningful progress
- **5-6**: Partially helpful action or correct action with strictly better alternatives
- **3-4**: Off-target action that provides minimal progress
- **1-2**: Incorrect action that wastes time or moves away from the goal

## Unzipping the Screenshots

Due to large number of images and for easier upload/download from huggingface, we have zipped the screenshots using the script (`organize_and_zip_screenshots.py`).
Before using the dataset you need to unzip the screenshots using the included `unzip_screenshots.py` script.

## Unzipping the Trajectories

Due to large number of trajectory files and for easier upload/download from huggingface, we have zipped the trajectories using the script (`zip_trajectories.py`).
Before using the dataset you need to unzip the trajectories using the included `unzip_trajectories.py` script.

## Example Use Case

```python
import json

# Load a trajectory
with open('taskAllrecipes--20-2.json', 'r') as f:
    trajectory = json.load(f)

# Extract high-quality steps (score >= 8)
high_quality_steps = [
    conv for conv in trajectory['conversations']
    if conv.get('from') == 'assistant' and conv.get('score', 0) >= 8
]

print(f"Total steps: {len([c for c in trajectory['conversations'] if c.get('from') == 'assistant'])}")
print(f"High-quality steps: {len(high_quality_steps)}")
```

## Dataset Statistics

- **Domain**: Web navigation and interaction tasks
- **Task Types**: Information retrieval, multi-step searches, form interactions
- **Websites**: Allrecipes, and other common web platforms
- **Average Trajectory Length**: Varies by task complexity
- **Score Distribution**: Detailed distribution available in paper

## Citation

If you use this dataset, please cite:

```bibtex
@article{he2025scalable,
  title={Scalable Data Synthesis for Computer Use Agents with Step-Level Filtering},
  author={He, Yifei and Chawla, Pranit and Souri, Yaser and Som, Subhojit and Song, Xia},
  journal={arXiv preprint arXiv:2512.10962},
  year={2025}
}
```

## License

This dataset is released under the [Community Data License Agreement - Permissive - Version 2.0 (CDLA-Permissive-2.0)](https://cdla.dev/permissive-2-0/).

The CDLA-Permissive-2.0 is a permissive license designed specifically for data sharing, allowing you to:
- Use, modify, and share the data freely
- Create and share results (including ML models) without restrictions
- No obligation beyond including this license text when sharing the data

See the [LICENSE.txt](LICENSE.txt) file for the complete license text.

## Contact

For questions or issues regarding the dataset, please reach out to the authors listed in the paper.

## Acknowledgments

This dataset incorporates queries from the [OpenWebVoyager](https://github.com/minorjerry/openwebvoyager) project, described in "Building Multimodal Web Agents via Iterative Real-World Exploration, Feedback and Optimization" (He et al., arXiv:2410.19609, 2024). We thank the authors for making their work available under the Apache License 2.0.
