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Engineering

Sarah Chen7 min
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Training an AI agent to use a computer feels like teaching a junior engineer on the job. You need thousands of realistic tasks, varied environments, and clear outcomes. Real interaction data helps, but it is expensive, slow, and messy. Synthetic data offers a way to generate that training material at scale. The key is to use it to make your model smarter, which produces better synthetic data. That is the data flywheel.

What the data flywheel actually looks like

Imagine you have a model that can perform basic computer tasks: navigating a browser, clicking buttons, filling forms. You evaluate it on a benchmark. Its performance is mediocre. To improve, you collect more real-world tasks. That takes time. You clean logs, label failures, and curate examples. Then you fine-tune the model. Performance goes up a few points. Now you can generate more challenging scenarios faster and cheaper. Each cycle sharpens the model, which sharpens the data. Over time, the model can handle edge cases and rare workflows that were previously invisible. This cycle is the data flywheel.

Real numbers from synthetic data experiments

Synthetic data is not magic. It works when you control the environment and validate the outputs. In recent evaluations, teams that added synthetic data to their training pipeline saw a 15‑20 percent lift on downstream tasks. Cost dropped because they no longer had to pay human annotators for every edge case. One engineering team reported that synthetic browser navigation tasks reduced their validation time by 40 percent while maintaining benchmark scores. The numbers come down to control and scale. You can generate thousands of unique interactions in a controlled environment, label them automatically, and feed them to your model. The model gets more examples than it would ever see in the wild.

Tradeoffs and best practices

  • Start with a small curated benchmark and measure baseline performance.
  • Generate synthetic tasks that mirror real-world complexity, not just toy examples.
  • Validate synthetic trajectories against real interactions before bulk use.
  • Use synthetic data for hard cases and rare workflows, not for everyday tasks.
  • Iterate: let the model improve, then regenerate more challenging scenarios.

The most effective flywheels begin with high quality, realistic interaction data and a process that turns model improvements into better data.

How Coasty fits into the flywheel

Coasty runs computer use agents on real desktops and browsers. This setup captures realistic interaction data, including clicks, keystrokes, screen states, and outcomes. The team can turn those interactions into custom synthetic datasets and trajectories for your model. This is not a self-serve product with fixed packages. It is a custom, contact-led service tailored to your use case. You talk to the Coasty data team, define your requirements, and they build the dataset that powers your flywheel.

Synthetic data can turn a static dataset into a self-improving flywheel. If you want to see how Coasty can help you build custom synthetic datasets for your agents, book a data call with the Coasty data team at https://cal.com/coasty/coasty-data-call.

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