Craig Hewitt, founder of the podcast hosting platform Castos, joined this episode of Zero to Agent in 30 Minutes to show how he uses the Codex application’s voice mode to run his development environment without touching the keyboard. Craig walked through what voice mode actually is, how it differs from dictation tools, and how he uses it to control his browser and other applications on his computer.
Setting up Codex for hands-free development, step by step
- Set up browser and computer access. Enable computer use in the Codex app and configure browser access so the agent can work with websites and other applications. Craig recommended requiring approval before the agent accesses most applications or sites.
- Start a voice session. Launch voice mode and give the agent instructions conversationally. Craig showed that the voice interface remains available as you move among applications, allowing you to direct work across your computer without repeatedly returning to the chat.
- Give the agent browser tasks. Craig asked the agent to open websites, search for information, and navigate pages. He also described using browser control for routine jobs such as completing forms when the agent already has the necessary context.
- Let the agent work across applications. Computer use extends the workflow beyond the browser. In Craig’s demonstration, the agent opened Cursor, found a specific repository, reported on uncommitted changes, and later committed those changes after receiving permission.
- Add specific page content to the conversation. Craig showed how you can select part of a web page and add it directly to the chat. That gives the agent the context needed to act on a particular element, such as a section of an interface you want to change.
- Keep permissions narrow. Browser and computer control create real risks, including unintended actions and prompt injection from web content. Craig said he requires approval for most applications, grants broader access only to selected tools and local development sites, and avoids sites he doesn’t trust.
Voice mode let Craig direct browser, application, and coding tasks through conversation. The demo also raised a real question about delegation. Once an agent can act on your behalf, you have to decide what you’re actually comfortable handing off. Craig used permission settings, a list of trusted sites, and human review to manage that.
Coming next week
In the next episode of Zero to Agent in 30 Minutes, Jayeeta Putatunda, forward deployed AI engineering lead at Turing, will build an agent that helps financial analysts keep up with a constant stream of new information. She’ll show how the agent categorizes financial news, ranks stories against analysts’ coverage profiles, and explains why each development may deserve attention.
