Simon Willison: LinkedIn Content Strategy & Writing Style

I've had preview access to GPT-5 for a couple of weeks, so I have a lot to say about it. Here's my first post, focusing just on core characteristics, pricing (it's VERY competitively priced) and inter…

I see a lot of complaints about untested AI slop in pull requests. Submitting those is a dereliction of duty as a software engineer: Your job is to deliver code you have proven to work

I published my third annual roundup of the last twelve months in LLMs. This one has 26 sections, starting with reasoning models and coding agents and working through Chinese open weight models, vibe c…

Over the past two years I've built more than 150 little "HTML tools" - single page interactive HTML+JavaScript utilities that do one useful thing. Almost all of them were vibe-coded with the assistan…

I wrote about "Designing agentic loops" - a new key skill that's needed to get the most out of coding agents like Anthropic's Claude Code and OpenAI's Codex CLI. A surprisingly large number of diffic…

Chinese AI lab Z.ai (previously called Zhipu AI) released two new MIT licensed open weight LLMs yesterday - GLM-4.5 and GLM-4.5 Air - and they are very impressive. Here are my initial impressions form…