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Amazon shipped a UI testing stack where the test is written as intent and an agent writes the steps

AspireAI community · Amazon Web Services
This post walks through Epsilon's architecture for delivering UI testing as a managed platform service, with the core integration code for Amazon Nova Act and the Amazon Bedrock AgentCore Browser Tool, a concrete 18-step test workflow, and measured results. The motivation is coverage rather than replacement: scripted Playwright tests remain good for deterministic regression checks, but they are tightly coupled to selectors and page structure, so cosmetic UI changes break them even when the functionality is fine, and multiple product teams each needed full coverage of their own applications. Nova Act supplies the intent-driven layer, with the AgentCore Browser Tool providing the browser interface. One practical gotcha the authors flag for anyone following along: account for the Browser Tool's viewport defaults when writing steps, since a step that says scroll down until a textbox is visible depends on how Nova Act handles content in the lower part of the page. Sample code for the Nova Act plus AgentCore Browser Tool integration is published on GitHub. It is a vendor architecture write-up on someone else's deployment, so treat the reported results as that team's, not a benchmark.
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