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Two publishers and three authors fail to understand what “vibe coding” means

Visit Two publishers and three authors fail to understand what "vibe coding" means

Vibe coding does not mean “using AI tools to help write code”. It means “generating code with AI without caring about the code that is produced”. See Not all AI-assisted programming is vibe coding for my previous writing on this subject. This is a hill I am willing to die on. I fear it will be the death of me.

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Understanding the recent criticism of the Chatbot Arena

Visit Understanding the recent criticism of the Chatbot Arena

The Chatbot Arena has become the go-to place for vibes-based evaluation of LLMs over the past two years. The project, originating at UC Berkeley, is home to a large community of model enthusiasts who submit prompts to two randomly selected anonymous models and pick their favorite response. This produces an Elo score leaderboard of the “best” models, similar to how chess rankings work.

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Qwen 3 offers a case study in how to effectively release a model

Visit Qwen 3 offers a case study in how to effectively release a model

Alibaba’s Qwen team released the hotly anticipated Qwen 3 model family today. The Qwen models are already some of the best open weight models—Apache 2.0 licensed and with a variety of different capabilities (including vision and audio input/output).

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Watching o3 guess a photo’s location is surreal, dystopian and wildly entertaining

Visit Watching o3 guess a photo's location is surreal, dystopian and wildly entertaining

Watching OpenAI’s new o3 model guess where a photo was taken is one of those moments where decades of science fiction suddenly come to life. It’s a cross between the Enhance Button and Omniscient Database TV Tropes.

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Exploring Promptfoo via Dave Guarino’s SNAP evals

Visit Exploring Promptfoo via Dave Guarino's SNAP evals

I used part three (here’s parts one and two) of Dave Guarino’s series on evaluating how well LLMs can answer questions about SNAP (aka food stamps) as an excuse to explore Promptfoo, an LLM eval tool.

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AI assisted search-based research actually works now

Visit AI assisted search-based research actually works now

For the past two and a half years the feature I’ve most wanted from LLMs is the ability to take on search-based research tasks on my behalf. We saw the first glimpses of this back in early 2023, with Perplexity (first launched December 2022, first prompt leak in January 2023) and then the GPT-4 powered Microsoft Bing (which launched/cratered spectacularly in February 2023). Since then a whole bunch of people have taken a swing at this problem, most notably Google Gemini and ChatGPT Search.

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Maybe Meta’s Llama claims to be open source because of the EU AI act

Visit Maybe Meta's Llama claims to be open source because of the EU AI act

I encountered a theory a while ago that one of the reasons Meta insist on using the term “open source” for their Llama models despite the Llama license not actually conforming to the terms of the Open Source Definition is that the EU’s AI act includes special rules for open source models without requiring OSI compliance.

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Image segmentation using Gemini 2.5

Visit Image segmentation using Gemini 2.5

Max Woolf pointed out this new feature of the Gemini 2.5 series (here’s my coverage of 2.5 Pro and 2.5 Flash) in a comment on Hacker News:

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GPT-4.1: Three new million token input models from OpenAI, including their cheapest model yet

Visit GPT-4.1: Three new million token input models from OpenAI, including their cheapest model yet

OpenAI introduced three new models this morning: GPT-4.1, GPT-4.1 mini and GPT-4.1 nano. These are API-only models right now, not available through the ChatGPT interface (though you can try them out in OpenAI’s API playground). All three models can handle 1,047,576 tokens of input and 32,768 tokens of output, and all three have a May 31, 2024 cut-off date (their previous models were mostly September 2023).

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CaMeL offers a promising new direction for mitigating prompt injection attacks

Visit CaMeL offers a promising new direction for mitigating prompt injection attacks

In the two and a half years that we’ve been talking about prompt injection attacks I’ve seen alarmingly little progress towards a robust solution. The new paper Defeating Prompt Injections by Design from Google DeepMind finally bucks that trend. This one is worth paying attention to.

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Model Context Protocol has prompt injection security problems

Visit Model Context Protocol has prompt injection security problems

As more people start hacking around with implementations of MCP (the Model Context Protocol, a new standard for making tools available to LLM-powered systems) the security implications of tools built on that protocol are starting to come into focus.

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Long context support in LLM 0.24 using fragments and template plugins

Visit Long context support in LLM 0.24 using fragments and template plugins

LLM 0.24 is now available with new features to help take advantage of the increasingly long input context supported by modern LLMs.

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Initial impressions of Llama 4

Dropping a model release as significant as Llama 4 on a weekend is plain unfair! So far the best place to learn about the new model family is this post on the Meta AI blog. They’ve released two new models today: Llama 4 Maverick is a 400B model (128 experts, 17B active parameters), text and image input with a 1 million token context length. Llama 4 Scout is 109B total parameters (16 experts, 17B active), also multi-modal and with a claimed 10 million token context length—an industry first.

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Putting Gemini 2.5 Pro through its paces

Visit Putting Gemini 2.5 Pro through its paces

There’s a new release from Google Gemini this morning: the first in the Gemini 2.5 series. Google call it “a thinking model, designed to tackle increasingly complex problems”. It’s already sat at the top of the LM Arena leaderboard, and from initial impressions looks like it may deserve that top spot.

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New audio models from OpenAI, but how much can we rely on them?

Visit New audio models from OpenAI, but how much can we rely on them?

OpenAI announced several new audio-related API features today, for both text-to-speech and speech-to-text. They’re very promising new models, but they appear to suffer from the ever-present risk of accidental (or malicious) instruction following.

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Calling a wrap on my weeknotes

After 192 posts that ranged from weekly to roughly once-a-month, I’ve decided to call a wrap on my weeknotes habit. The original goal was to stay transparent during my 2019-2020 JSK fellowship, and I kept them up after that as an accountability mechanism and to get into a habit of writing regularly.

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Not all AI-assisted programming is vibe coding (but vibe coding rocks)

Vibe coding is having a moment. The term was coined by Andrej Karpathy just a few weeks ago (on February 6th) and has since been featured in the New York Times, Ars Technica, the Guardian and countless online discussions.

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Adding AI-generated descriptions to my tools collection

Visit Adding AI-generated descriptions to my tools collection

The /colophon page on my tools.simonwillison.net site lists all 78 of the HTML+JavaScript tools I’ve built (with AI assistance) along with their commit histories, including links to prompting transcripts. I wrote about how I built that colophon the other day. It now also includes a description of each tool, generated using Claude 3.7 Sonnet.

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Notes on Google’s Gemma 3

Visit Notes on Google's Gemma 3

Google’s Gemma team released an impressive new model today (under their not-open-source Gemma license). Gemma 3 comes in four sizes—1B, 4B, 12B, and 27B—and while 1B is text-only the larger three models are all multi-modal for vision:

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Here’s how I use LLMs to help me write code

Visit Here's how I use LLMs to help me write code

Online discussions about using Large Language Models to help write code inevitably produce comments from developers who’s experiences have been disappointing. They often ask what they’re doing wrong—how come some people are reporting such great results when their own experiments have proved lacking?

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What’s new in the world of LLMs, for NICAR 2025

Visit What's new in the world of LLMs, for NICAR 2025

I presented two sessions at the NICAR 2025 data journalism conference this year. The first was this one based on my review of LLMs in 2024, extended by several months to cover everything that’s happened in 2025 so far. The second was a workshop on Cutting-edge web scraping techniques, which I’ve written up separately.

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I built an automaton called Squadron

Visit I built an automaton called Squadron

I believe that the price you have to pay for taking on a project is writing about it afterwards. On that basis, I feel compelled to write up my decidedly non-software project from this weekend: Squadron, an automaton.

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Notes from my Accessibility and Gen AI podcast appearance

Visit Notes from my Accessibility and Gen AI podcast appearance

I was a guest on the most recent episode of the Accessibility + Gen AI Podcast, hosted by Eamon McErlean and Joe Devon. We had a really fun, wide-ranging conversation about a host of different topics. I’ve extracted a few choice quotes from the transcript.

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Hallucinations in code are the least dangerous form of LLM mistakes

A surprisingly common complaint I see from developers who have tried using LLMs for code is that they encountered a hallucination—usually the LLM inventing a method or even a full software library that doesn’t exist—and it crashed their confidence in LLMs as a tool for writing code. How could anyone productively use these things if they invent methods that don’t exist?

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Structured data extraction from unstructured content using LLM schemas

Visit Structured data extraction from unstructured content using LLM schemas

LLM 0.23 is out today, and the signature feature is support for schemas—a new way of providing structured output from a model that matches a specification provided by the user. I’ve also upgraded both the llm-anthropic and llm-gemini plugins to add support for schemas.

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Initial impressions of GPT-4.5

Visit Initial impressions of GPT-4.5

GPT-4.5 is out today as a “research preview”—it’s available to OpenAI Pro ($200/month) customers and to developers with an API key. OpenAI also published a GPT-4.5 system card.

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Claude 3.7 Sonnet, extended thinking and long output, llm-anthropic 0.14

Visit Claude 3.7 Sonnet, extended thinking and long output, llm-anthropic 0.14

Claude 3.7 Sonnet (previously) is a very interesting new model. I released llm-anthropic 0.14 last night adding support for the new model’s features to LLM. I learned a whole lot about the new model in the process of building that plugin.

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LLM 0.22, the annotated release notes

I released LLM 0.22 this evening. Here are the annotated release notes:

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Run LLMs on macOS using llm-mlx and Apple’s MLX framework

Visit Run LLMs on macOS using llm-mlx and Apple's MLX framework

llm-mlx is a brand new plugin for my LLM Python Library and CLI utility which builds on top of Apple’s excellent MLX array framework library and mlx-lm package. If you’re a terminal user or Python developer with a Mac this may be the new easiest way to start exploring local Large Language Models.

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URL-addressable Pyodide Python environments

Visit URL-addressable Pyodide Python environments

This evening I spotted an obscure bug in Datasette, using Datasette Lite. I figure it’s a good opportunity to highlight how useful it is to have a URL-addressable Python environment, powered by Pyodide and WebAssembly.

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