Stitch Bug: Internal agent/debug response rendered directly inside generated UI

Stitch
1

Hi Stitch team,

I encountered what appears to be a rendering bug while generating a UI in Stitch.

Instead of displaying only the generated interface, the page rendered what looks like the agent’s internal response/debug output (JavaScript/JSON-like content) directly inside the UI.

Expected Behavior

  • Stitch should render only the generated UI.
  • Any internal agent responses, reasoning, JSON, logs, or debugging information should remain hidden from the user.

Actual Behavior

After the UI generation completed, a large block of internal text appeared inside the generated screen.

The output contained implementation/debug-related content such as references to:

  • agentCursor
  • imageRevealRunning
  • clearInterval
  • DOM manipulation code
  • other internal JavaScript-like logic

This text became part of the generated interface, making the UI unusable.

Steps to Reproduce

  1. Open Stitch.
  2. Enter a prompt to generate a UI.
  3. Wait for generation to finish.
  4. The generated UI may render the agent’s internal/debug output instead of only the intended interface.

(I haven’t found a deterministic way to reproduce it yet—it happened during a normal UI generation.)

Environment

  • Platform: Stitch (Web)
  • Browser: Google Chrome
  • Operating System: macOS

Screenshot

Screenshot 2026-07-16 at 11.09.52 AM
Screenshot 2026-07-16 at 11.09.52 AM257×552 66.4 KB

The screenshot shows the generated card, where the lower portion contains internal JavaScript/debug output instead of UI components.

Why this matters

This isn’t just a visual glitch—it appears that internal implementation/debug information is being rendered directly in the generated interface.

Potential impacts include:

  • Broken generated UI
  • Poor user experience
  • Possible exposure of internal implementation details
  • Reduced confidence in generated results

Has anyone else experienced this issue? If so, it would be helpful to know whether it’s specific to certain prompts or models.

Thanks!