Simon Willison — 2026-06-12#

Highlight#

Simon updated his OpenAI WebRTC audio playground to support the newly released GPT-Realtime-2 model and added support for custom document context. This highlights a great use case for building small, sharp tools: bypassing official app delays to immediately experiment with bleeding-edge AI capabilities on your own terms.

Posts#

OpenAI WebRTC Audio Session, now with document context · Source Simon revisited and upgraded a browser-based tool he originally built in December 2024 for interacting with OpenAI’s realtime audio API. Users can now select GPT-Realtime-2—a model promoted as having “GPT-5-class reasoning”—because it still hasn’t rolled out to the official ChatGPT iPhone app. Most practically, he added a feature to paste large chunks of document context directly into the tool, enabling interactive audio conversations grounded in specific reference material.