Simon Willison (@simonwillison.net): Made myself a custom Codex pet today (you'll never guess what it was), and had some fun reverse-engineering how the feature works - it generates animated sprite sheets using gpt-image-2 simonwillison.

Simon Willison documents his experience using Claude Code to port the Moebius 0.2B image inpainting model to ONNX format for browser-based execution via WebGPU. He walks through the agent-assisted conversion process and shares a working demo that allows image inpainting directly in the browser without CUDA dependencies.

Simon Willison shares practical tips for optimizing Claude Code's Fable agent, including letting the AI use its own judgment for testing decisions and delegating coding tasks to lower-power subagents to save tokens. The article provides specific prompt examples and real-world results showing improved cost efficiency while maintaining productivity.

This OpenAI Cookbook tutorial demonstrates how to build a speaker-aware meeting intelligence pipeline using audio diarization and transcription. It provides practical code examples for processing meeting audio to identify different speakers and generate structured meeting notes. The guide covers the technical implementation details and architecture for creating an automated meeting analysis system.

Simon Willison shares a cache-friendly approach for running Python tools with uvx in GitHub Actions, using the UV_EXCLUDE_NEWER environment variable to create deterministic cache keys without needing additional dependency files. The technique allows tools to be cached between workflow runs while providing a simple way to bust the cache when needed. This solves the problem of uvx repeatedly downloading packages from PyPI on every workflow execution.

Simon Willison documents creating a custom animated desktop pet named 'Pedalican' using Codex Desktop's pet feature. The article details how GPT-5.6 Sol generated animated sprites through multiple rounds with gpt-image-2, including all prompts and generated assets. It explores using image generation for game-ready sprites and points to the open-source implementation details published by OpenAI.