Simon Willison

.blend URL Viewer

Simon Willison created a .blend URL Viewer tool that lets users view a Blender model of a Fabergé egg themed after the TV show Pluribus directly in their browser. He generated the egg image using ChatGPT Images 2.5, then fed it to GPT‑6 Astra with a custom Blender skill to produce several .blend files. The viewer, built with JavaScript, is now part of his tools collection for easy access to the resulting 3D model.

Simon Willison
Sep 26

Kākāpō Party

Simon Willison presented a closing keynote at the WeAreDevelopers World Congress North America, where he showcased a pixel‑art animation of kakapo parrots celebrating a record‑breaking breeding season in 2026. He used Claude Opus 5.5 to generate the animation from Google‑searched kakapo photos, then employed Claude Code with Playwright to record a 15‑second video of the animated HTML5 canvas, which he embedded in his Keynote slide.

Simon Willison
Sep 5

Introducing GPT-6 Astra for developers

Simon Willison introduces GPT‑6 Astra, a new model that offers improved attention to detail, better prompt comprehension, and the ability to generate more sophisticated outputs. The model excels at creating 3D renderings, producing detailed scenes such as gardens, shipyards, animals, cityscapes, and even Dyson spheres. Willison highlights its whimsical creativity, noting examples like a pelican wearing a red neckerchief riding a bicycle.

Simon Willison
Sep 5

Using Blender with coding agents on macOS

Simon Willison demonstrates how to use Blender with coding agents on macOS by installing the full Mac application from blender.org and issuing prompts to ChatGPT Codex. He shows a step-by-step example where the agent renders a scene of a pelican riding a bicycle, then adds background flair and improves the image. The resulting image is generated via Blender's Python API.

Simon Willison
Sep 4

The Pelican comparison grid for Astra is pretty interesting

Simon Willison tested GPT‑6 Astra by generating SVG pelicans riding bicycles at various reasoning levels and compared the results to GPT‑5.6 Sol, Terra, and Luna. The Astra pelicans consistently outperformed the other models, especially at low and xhigh reasoning levels, and even the Astra max version produced high‑quality images. Astra also used fewer tokens and was roughly twice as expensive as Sol, yet its low‑level output was cheaper and superior to any Sol model.

Simon Willison
Oct 21

Panache — RTS Belle Époque pour mobile

Panache is a real‑time strategy game for mobile and browser set in France’s Belle Époque around 1900, featuring steampunk elements such as dirigibles, steam‑powered trucks, armored ships, and marching fortresses. The game was released under an Apache 2.0 license and already has a French‑language fork that reskins it to a steampunk 1900s France, adding an animated intro and French‑twisted music. The updates are mainly aesthetic, with new models and an intro video showcased on the game’s page.

Simon Willison
Oct 13

llm-gemini 0.35

The article announces the release of llm‑gemini 0.35, adding support for the new Gemini 4 Argon model available through the Gemini API and for customers on the $100/month subscription plan. It highlights Argon’s pricing—$2/million input and $10/million output at launch, with a planned price increase on December 1st—and compares its cost-effectiveness to other models, noting it remains cheaper than many competitors even after the increase. The post also showcases example SVG outputs and creative illustrations generated by Argon, such as a pelican riding a bicycle and an armadillo in fishnet tights on Mars.

Simon Willison
Sep 29

GPT 6.1 Sol: Near-Astra intelligence for a fifth of the price

Simon Willison comments on GPT 6.1‑Sol, describing it as "Near‑Astra intelligence for a fifth of the price." He notes that the model’s pelican illustrations are similar to those of the GPT‑6 family and provides links to the live‑blog of the keynote and to the pelican images. The post is tagged with AI, OpenAI, generative‑AI, LLMs, and playful references to pelican‑riding‑a‑bicycle.

Simon Willison
Oct 23

Quick Study

Quick Study is a tool that lets users open a photo and quickly generate a painted version of it using a canvas element and a simulated paintbrush. The process relies on Sobel edge detection and requires no external libraries beyond Google Fonts. It builds on previous experiments that used Claude Fable to create watercolor illustrations with P5.js.

Simon Willison
Oct 28

The October inflection point for vibe game development

Simon Willison discusses a new inflection point in October 2026 for creating video games using AI, noting that Claude Opus 5.5 now reliably produces compelling 3D models, music, and especially game design. He reports having successfully "vibe coded" four enjoyable games without inspecting the code, and highlights that the real challenge is now generating novel, delightful concepts that AI alone could not conceive. The author compares Opus 5.5’s fun factor to GPT‑6 Astra, which he finds lacking in that regard.

Simon Willison
Sep 8

Introducing ChatGPT Images 2.5

Simon Willison announces the release of ChatGPT Images 2.5, noting that OpenAI’s image generation models have processed over 3 billion images across ChatGPT Images and the GPT‑Image API. The new version improves instruction‑following across multiple turns, speeds up responses, and better preserves subjects from reference photos. Two new API model IDs—gpt‑image‑2.5‑sunburst and gpt‑image‑2.5‑flare—are available, with Sunburst recommended for precision editing and Flare for fast, high‑quality everyday generation. Willison has updated his openai_image.py CLI tool to accept reference images, demonstrating its use with a raccoon scientist prompt.

Simon Willison
Oct 14

Tree Appreciator

Simon Willison describes a game experiment called "Tree Appreciator" created with Claude Opus 5.5 Max. The game, built in three.js, presents two algorithmically generated trees and challenges players to appreciate their differences through a spot‑the‑difference style mechanic. After three hours and seven minutes of processing, Claude produced a polished, music‑and‑animation‑rich game with achievements that feels both fun and beautiful.