Theo on Using an AI Agent to Test Debugging Hypotheses

When a model could not find a problem on its own, Theo asked it to build a tool for testing his theories.

TBTheo BrowneSpeaker · Ping Labs
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Theo - t3․gg
Published
Aug 5, 2026
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0:42
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SUMMARY

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Theo Browne describes changing his approach after an AI model failed to identify or fix a problem. He used the agent to locate relevant code and build a browser-console tool, while bringing his own observations and hypotheses to the investigation.

  1. 1Change the questionWhen the model could not find or fix the problem, Theo shifted to testing multiple hypotheses.
  2. 2Build a testing toolHe asked for changes that could be tried in production through console commands and observed immediately.
  3. 3Divide the workThe agent found code and built tools quickly; Theo contributed the information and theories that guided the work.

Takeaways

  1. An AI model may help investigate a problem even when it cannot identify the cause itself.
  2. Theo asked the agent to build a console-accessible tool for testing changes quickly.
  3. The agent accelerated code discovery and experimentation while Theo supplied the observations and theories.
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01

Using the model to investigate

Theo describes moving from asking a model to solve a problem to using it to test theories. A custom browser tool lets him change options and observe the effects.

At this point I realized the model was not going to solve the problem for me, or even find it. So I changed my mindset: instead of waiting for an answer, I thought about how to use the model to test as many different debugging theories as efficiently as possible.

Request for a production debugging helper
SLIDE 1 / 1Request for a production debugging helperThe screen shows Theo asking for changes he can test through console commands, followed by an agent-generated helper.

I asked it to make changes easy to experiment with in production, ideally through console commands so I could see an immediate difference. It wrote a window binding that created __T3GPU, giving us a custom tool for switching options back and forth while investigating.

The agent could find things in the codebase faster than I could and build custom tools to test my theories better than I could. But I was still the one bringing the actual information to the investigation.

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