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Research

David Park7 min
Del

Training a self-improving agent feels like a puzzle with a missing piece. You have a model, an environment, and a feedback loop, but the loop stagnates because you do not have enough high-quality labeled data. Real data is expensive, sensitive, or simply not available at the scale you need. Synthetic data fills that gap, turning a static dataset into a continuous, self-improving flywheel.

The data flywheel in practice

A data flywheel is a loop where fresh, high-quality data improves the agent, which then generates more realistic data, which makes the agent even better. The loop works when you can reliably measure performance and feed that signal back into training. Synthetic data accelerates every stage. For example, a research team used synthetic trajectories to train a computer-use agent on a new web interface. After three training rounds, the agent reduced task completion time by 34 percent and reached a 92 percent success rate on a realistic benchmark suite. The team then used the same synthetic trajectories to evaluate a new model architecture, which proved 8 points more robust to edge cases than the previous best model. This pattern repeats: better agents produce better synthetic data, which leads to even better agents.

Why synthetic data matters for self-improving agents

  • Scale: You can generate millions of realistic interaction sequences in days, not months.
  • Coverage: Synthetic data can deliberately include rare scenarios, edge cases, and adversarial inputs that are hard to find in production.
  • Privacy: Training on synthetic user interactions avoids exposing real user data, simplifying compliance and reducing legal risk.
  • Control: You can control the difficulty, complexity, and success criteria of each trajectory, making it easier to align the agent with your goals.
  • Reproducibility: Synthetic data is versioned and deterministic, which helps you compare model changes and track progress reliably.

The data flywheel requires a reliable source of realistic, high-fidelity interaction data to keep the loop spinning.

Common pitfalls and how to avoid them

Not all synthetic data is equally useful. The biggest risk is over-reliance on low-fidelity simulations that miss the nuances of real tasks. For example, a model trained only on simple click sequences struggled when faced with complex, multi-step workflows involving dynamic UI elements. The fix is to ground synthetic trajectories in real-world interaction patterns. Use real environments to capture authentic user behavior, then generate synthetic trajectories that preserve those patterns while expanding coverage. Another pitfall is ignoring evaluation on real data. Synthetic data should supplement, not replace, real-world testing. A balanced approach is to use synthetic data for rapid iteration and for evaluating edge cases, then validate key performance metrics on a smaller set of real tasks.

How Coasty fits into the flywheel

Coasty runs computer-use agents on real desktops and browsers to capture realistic interaction data. This approach ensures that synthetic trajectories reflect actual task flows, UI dynamics, and user intent. The team can build custom synthetic datasets tailored to your specific domain, workflow, and success criteria. The offering is custom and contact-led, meaning you work directly with Coasty data experts to define the scope, generate the data, and integrate it into your training and evaluation pipelines. No fixed packages or self-service dashboards are available. The focus is on delivering high-quality, realistic data that powers your data flywheel.

A data flywheel demands a continuous supply of realistic, high-fidelity interaction data. Coasty can help you build that supply through custom synthetic datasets grounded in real-world computer use. To explore how Coasty can support your data flywheel, book a data call with the Coasty data team at https://cal.com/coasty/coasty-data-call .

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