TLDR: CrowdAgent is a multi-agent system that streamlines data annotation by dynamically managing Large Language Models (LLMs), Small Language Models (SLMs), and human experts. It uses specialized agents for annotation, quality assurance, financing, and scheduling to optimize for both high accuracy and low cost across diverse tasks, significantly outperforming existing methods and reducing expenses. The system provides end-to-end process control, mimicking real-world crowdsourcing companies to achieve an optimal balance between label quality and annotation cost.
High-quality annotated data is the foundation for advancements in modern Artificial Intelligence, especially in Natural Language Processing. However, generating this data efficiently and accurately presents significant challenges. Traditional methods, such as manual crowdsourcing, can be expensive and labor-intensive, particularly for specialized tasks. While Large Language Models (LLMs) offer strong zero-shot capabilities and lower costs, relying solely on them can lead to inaccuracies due to inherent biases.
Recent approaches have tried to combine multiple annotation sources, including LLMs, Small Language Models (SLMs), and human experts. Yet, many of these solutions often focus narrowly on the labeling step itself, lacking a comprehensive system for dynamic process control, complex scheduling, and managing the trade-offs between quality and cost in a unified way.
Introducing CrowdAgent: A Multi-Agent System for Data Annotation
Inspired by the operational workflows of real-world crowdsourcing companies, researchers Maosheng Qin, Renyu Zhu, Mingxuan Xia, Chenkai Chen, Zhen Zhu, Minmin Lin, Junbo Zhao, Lu Xu, Changjie Fan, Runze Wu, and Haobo Wang have introduced CrowdAgent, a novel multi-agent system designed to provide end-to-end process control for multi-source data annotation. This system integrates task assignment, data annotation, and quality/cost management into a cohesive framework, allowing LLMs, SLMs, and human experts to collaborate synergistically.
CrowdAgent emulates a virtual annotation company with intelligent agents, each having a specific role and skills. These agents learn from past decisions and outcomes, continuously refining their strategies.
The Core Components of CrowdAgent
The system is built around four main types of agents:
Annotation Agents: These are the primary units involved in labeling data. They consist of:
- LLM Annotators: Multiple LLM agents are instantiated using diverse prompt designs to offer different perspectives on the task, enhancing robustness.
- SLM Annotators: Small deep models are trained using noisy-label learning techniques to purify labels from potentially noisy LLM outputs.
- Human Annotators: Human experts provide judgment on the most challenging samples, strategically selected based on low confidence and diversity metrics. The system integrates with platforms like NetEase Youling Crowdsourcing Platform for seamless task dispatch.
Quality Assurance (QA) Agent: This agent evaluates label quality, aggregates labels using iterative Bayesian inference, and identifies error patterns. It generates detailed annotator profiles and personalized annotation guidelines to refine instructions for subsequent rounds.
Financing Agent: Responsible for financial oversight, this agent tracks expenses from all annotation sources (LLM API calls, SLM computations, human labor). It conducts continuous cost-effectiveness analysis, providing crucial data-driven insights for optimizing task allocation.
Scheduling Agent: Acting as the central manager, the Scheduling Agent dynamically dispatches tasks. It synthesizes performance history, cost analysis from the Financing Agent, and quality feedback from the QA Agent to assign each sample to the most suitable annotator, aiming for an optimal balance between label quality and annotation cost.
How CrowdAgent Works: An Iterative Workflow
The system operates through a multi-round workflow:
1. Cheap Initial Labels: LLMs perform large-scale initial annotation and refinement using dynamically curated in-context learning examples.
2. Denoising and Filtering: SLMs are robustly trained on the LLMs’ outputs, identifying and learning from clean samples.
3. Human-in-the-Loop Annotation: Unconverged samples are strategically assigned to human annotators, focusing on those with the lowest confidence scores and highest diversity to maximize impact.
This iterative process continues until predefined termination conditions are met, such as budget exhaustion or all samples achieving a target confidence score. If target accuracy isn’t met, the system flags the most challenging samples for final human verification.
Demonstrated Effectiveness and Cost Savings
CrowdAgent has been extensively tested on six diverse multimodal classification tasks, including CrisisMMD, MM-IMDb, COV-CTR, and V-SNLI. The experiments consistently show that CrowdAgent achieves higher annotation accuracy compared to baseline methods, even with the same proportion of human annotation. For instance, it demonstrated a 3.58% lead on the COV-CTR dataset and 5.47% on the Damage Severity task over strong baselines.
Crucially, CrowdAgent significantly reduces annotation costs. By intelligently scheduling tasks and assigning the majority of samples to cost-effective machine annotators, while reserving expensive human expertise for critical cases, the system achieves a superior quality-cost trade-off. This makes it a practical and economically viable solution for enterprises and research institutions needing high-quality datasets at scale.
Also Read:
- Adaptive AI Agents: Tailoring LLM Workflows for Smarter, Cheaper Solutions
- Collaborative AI Agents Enhance Prompt Optimization for Large Language Models
User-Friendly Interface and Future Outlook
The system also provides a user-friendly interface for task configuration, real-time monitoring of agent interactions, and visualization of key metrics like accuracy and budget consumption. Users can track the progress of individual annotators, analyze difficult samples, and review the decision logic of the agents.
While CrowdAgent offers a powerful solution, the researchers acknowledge limitations, such as handling residual errors from machine annotation (mitigated by human review) and the system’s reliance on the capabilities of underlying LLMs. Ethical considerations include potential societal biases from LLMs, the risk of human annotator redundancy, and conflicts with terms of use for knowledge distillation. Future work aims to incorporate a broader range of annotation sources and enhance scheduling intelligence.
For more in-depth information, you can read the full research paper here.


