Knowledge catalogue
GPT-5.5 is out. It's available in OpenAI Codex and is rolling out to paid ChatGPT subscribers. I've had some preview access and found it to be a fast, effective and highly capable model. As is usually
LlamaIndex have a most excellent open source project called LiteParse, which provides a Node.js CLI tool for extracting text from PDFs. I got a version of LiteParse working entirely in the browser, us
GPT-5.5 may not be in the official OpenAI API... but it's available via the apparently approved-of Codex API backdoor So I used that to make these pelicans (default and xhigh)! https://simonwillison.n
I've been previewing this in Codex for a few weeks - it's very good! Had some great results from it having it run security reviews against code written using other models Introducing GPT-5.5 A new cla
LiteParse is really neat! It does a great job of extracting text from annoying layouts in PDFs (multiple columns for example) It's only available as a Node.js CLI app, so I vibe-coded up this version
[...] if you ever needed another reason to learn in public by digital gardening or podcasting or streaming or whathaveyou, add on that people will assume you’re more competent than you are. This will
That browser version of LiteParse is available here: https://simonw.github.io/liteparse/ Detailed notes on how I built it using Claude Code (running for an hour) on my blog: https://simonwillison.net/
This is a lot of fun to try out - https://flipbook.page Imagine every pixel on your screen, streamed live directly from a model. No HTML, no layout engine, no code. Just exactly what you want to see.
Within two years you'll be able to prompt inject an entire country Under the directives of the President of the UAE, we launch a new government model. Within two years, 50% of government sectors, serv
Anthropic have now reverted the change to their pricing page, but I've not yet seen any official announcement about what their policies are going to be going forward. More on my blog: https://simonwil
Anthropic really did just hand this one to OpenAI on a plate I don't know what they are doing over there, but Codex will continue to be available both in the FREE and PLUS ($20) plans. We have the com
Anyone else able to duplicate the 34/month pricing for Claude Pro shown in this screenshot? https://x.com/sean_e_callahan/status/2046992927759413647 @simonw Anthropic pricing games? Claude site has Pr
Apparently my blog is mostly about token pricing now, here are some notes on the big changes GitHub Copilot just announced, including pausing new signups entirely https://simonwillison.net/2026/Apr/22
Apparently the bug was rolling out the new pricing grid worldwide when it should only have been seen by the 2% of people in the A/B test https://x.com/TheAmolAvasare/status/2046783926920978681 Getting
As far as I can tell this tweet buried in a thread is currently the ONLY official confirmation that this potential pricing change won't affect existing Pro subscribers When we do land on something, if
Changes to GitHub Copilot Individual plans On the same day as Claude Code's temporary will-they-won't-they 100/month kerfuffle (for the moment, they won't), here's the latest on GitHub Copilot pricing
Correction: OpenAI are NOT deprecating that model, the announcement was a mistake Thank you for flagging this, Jeff. This was a mistake: we are not deprecating text-embedding-3-small. We’re looking in
Has anyone seen ANY official communication from Anthropic or an Anthropic staff member about the fact that the checkbox for Claude Code on Pro is back to being checked again, or is the only evidence t
Anthropic today quietly (as in silently, no announcement anywhere at all) updated their claude.com/pricing page (but not their Choosing a Claude plan page, which shows up first for me on Google) to ad
I've been mostly prompting the new model directly via the client.images.generate() API, I have no idea if that rewrites my prompts at all or if it passes them straight to the model - details here http
New sandbox! Announcing Cloud Run sandboxes: Secure on-the-fly code execution: Spin up ephemeral, isolated sandboxes from within Cloud Run resources. Safely execute agent-generated code, scripts, or C
Not the first time either - they shut down a bunch of of their original proprietary hosted embedding models in this announcement back in April 2024 https://openai.com/index/gpt-4-api-general-availabil
Presumably GPT-imagegen-2 (aka ChatGPT Images 2.0 aka gpt-image-2) works as a tool which the models generate prompts for? I wish we could see those prompts, like back in the DALL-E 3 days https://simo
As part of our continued collaboration with Anthropic, we had the opportunity to apply an early version of Claude Mythos Preview to Firefox. This week’s release of Firefox 150 includes fixes for 271 v
Qwen3.6-27B: Flagship-Level Coding in a 27B Dense Model Big claims from Qwen about their latest open weight model: Qwen3.6-27B delivers flagship-level agentic coding performance, surpassing the previo
Thank you for flagging this, Jeff. This was a mistake: we are not deprecating text-embedding-3-small. We’re looking into where this came from now, and we’ll also email users to clarify. Sorry for the
That's from this ChatGPT conversation - https://chatgpt.com/share/69e90ba5-7760-83e8-9e09-f06e25a90930 - my prompt was 'Do a where's Waldo style image but it's where is the raccoon holding a ham radio
This post highlights the Qwen 3.6-27B language model's image generation capabilities, noting that despite its relatively compact 16.8GB file size, it produces high-quality creative outputs like the ex
This is a really big deal - it's easy to run into nasty bills with Cloud Run if your site attracts aggressive scrapers, spending caps make it a whole lot safer to run small projects on Anouncing Spend
This is why I won't use proprietary hosted embedding models myself - I am more than happy to pay for a hosted solution (cheaper, faster and more convenient than self-hosting) but I want an open weight
This post documents a method for extracting the text prompt used by an image generation AI by examining network traffic in a web browser's developer tools. Simon Willison demonstrates that prompts can
... which keeps things confusing, since it raises an important new question https://x.com/simonw/status/2046798283700617267 @TheAmolAvasare If I sign up for a new $20/month account today and roll the
Wrote up Anthropic's self-own about Claude Code pricing from this afternoon on my blog - it turned out they'd reversed course just as I hit publish, so I've tried to update it to reflect the current s
Claude Opus 4.7 with adaptive thinking via the API... am I missing something or is it not possible any more to force it to think? (Prompt hacks like 'think step by step' don't count here, I mean the e
I came up with a somewhat foolish new benchmark for testing image generation models, to exercise the new ChatGPT Images 2.0: 'Do a where's Waldo style image but it's where is the raccoon holding a ham
Simon Willison expresses hope that OpenAI will commit to long-term maintenance of an AI tool, citing concerns about his own tool potentially becoming stale or discontinued. The post reflects broader u
My hunch for now is that this was an ill-considered test which they didn't anticipate would be instantly spotted and cause (justified) uproar - here's hoping they decide that the 'test' isn't a good i
OK, here's a resolution - I managed to get it to think using these settings: 'thinking': { 'type': 'adaptive', 'display': 'summarized' }, 'output_config': { 'effort': 'max' } Without 'display': 'summa
OpenAI's new Euphony tool works almost exactly the same way as my Codex transcript viewer https://tools.simonwillison.net/codex-timeline?url=https%3A%2F%2Fgist.githubusercontent.com%2Fsimonw%2Fa9eb599
AI agents are already too human. Not in the romantic sense, not because they love or fear or dream, but in the more banal and frustrating one. The current implementations keep showing their human orig
scosman/pelicans_riding_bicycles I firmly approve of Steve Cosman's efforts to pollute the training set of pelicans riding bicycles. (To be fair, most of the examples I've published count as poisoning
This piece thinks that the reason I got a crap pelican riding a bicycle from Opus 4.7 is that it didn't think about it first, I'm trying to figure out if there's a way to force it to think that I've m
OpenAI has been using multiple informal names internally and externally for its new image generation model, including 'ChatGPT Images 2.0,' 'Image gen 2,' and 'gpt-image-2.' The post highlights incons
OpenAI released ChatGPT Images 2.0 today, their latest image generation model. On the livestream Sam Altman said that the leap from gpt-image-1 to gpt-image-2 was equivalent to jumping from GPT-3 to G
Claude Token Counter, now with model comparisons I upgraded my Claude Token Counter tool to add the ability to run the same count against different models in order to compare them. As far as I can tel
'I am envisioning a harmonious interplay of form and space, where each element finds its rightful place within the visual narrative. The pelican emerges as a central figure, its wings poised in dynami
Claude Opus 4.7 uses approximately 8% more tokens than Opus 4.6 when processing the same text-heavy PDF document, as demonstrated by a test comparing tokenization of a 15MB, 30-page PDF (60,934 tokens
Important to note: that 3x increase for images is entirely due to Opus 4.7 being able to handle higher resolutions. I tried that again with a 682x318 pixel image and it took 314 tokens with Opus 4.7 a
Simon Willison shared an experience attempting to use X's Community Notes feature to add clarification to his own tweet, experimenting with whether the self-noting functionality would work as intended
Release: llm-openrouter 0.6 llm openrouter refresh command for refreshing the list of available models without waiting for the cache to expire. I added this feature so I could try Kimi 2.6 on OpenRout
Simon Willison shared a tutorial on integrating Datasette instances with Google Sheets, demonstrating multiple methods including the importdata() function, custom named functions, and Google Apps Scri
TIL: SQL functions in Google Sheets to fetch data from Datasette I put together some notes on patterns for fetching data from a Datasette instance directly into Google Sheets - using the importdata()
Headless everything for personal AI Matt Webb thinks headless services are about to become much more common: Why? Because using personal AIs is a better experience for users than using services direct
Note to @AnthropicAI - much as I appreciate the public system prompts this would be so much more valuable to me as a Claude power user if you published the tool descriptions as well Since Anthropic pu
Simon Willison documents the differences between Anthropic's Claude Opus 4.6 and 4.7 system prompts, analyzing changes that Anthropic made public. The notes likely highlight modifications to model beh
The biggest challenge of using chat-based AI systems is that the details of what they can do are invisible - those tool descriptions are the missing manual, publishing them would be a huge benefit to
Agentic Engineering Patterns > Here's an example of a deceptively short prompt that got a lot of work done in a single shot. First, some background. I send out a free Substack newsletter around once a
Research: Claude system prompts as a git timeline Anthropic publish the system prompts for Claude chat and make that page available as Markdown. I had Claude Code turn that page into separate files fo
PyCon US 2026 will be held in Long Beach and will feature new dedicated tracks focused on AI and security topics. The announcement comes from Simon Willison, highlighting these expanded programming ar
The event is next month - talks are Friday 15th to Sunday 17th of May, with the date before that of tutorials and two days afterwards of sprints Californians are notoriously last-minute planners so I