Simon Willison on GPT-Live: major improvement in voice mode with an amusing uncontrolled laughter bug

Main idea

Simon Willison, who had preview access to GPT-Live, evaluated the model as significantly improved over previous GPT-4o era voice models. It makes a particularly good brainstorming partner. However, he encountered a peculiar bug: the model occasionally interrupted conversations with inappropriate laughter.

Context

GPT-Live is a fully duplex voice model released July 8, 2026 — it can listen and speak simultaneously, which is an architectural change from previous systems. Willison is one of few external reviewers with preview access.

Why it matters

High-quality voice AI has long been promised but hard to achieve. If GPT-Live genuinely moves the needle, this could accelerate AI adoption in scenarios where typing is not possible or appropriate.

Details / arguments

• Published: simonwillison.net, July 8, 2026, 11:20 PM
• Assessment: significantly improved over GPT-4o era model
• Particularly good for brainstorming
• Bug: inappropriate laughter interrupting conversations
• Architectural change: fully duplex (listens and speaks simultaneously)
• Delegates to GPT-5.5 for complex questions