Simon Willison’s Weblog

Codestral 25.01 (via) Brand new code-focused model from Mistral. Unlike the first Codestral this one isn't (yet) available as open weights. The model has a 256k token context - a new record for Mistral.

The new model scored an impressive joint first place with Claude 3.5 Sonnet and Deepseek V2.5 (FIM) on the Copilot Arena leaderboard.

Chatbot Arena announced Copilot Arena on 12th November 2024. The leaderboard is driven by results gathered through their Copilot Arena VS Code extensions, which provides users with free access to models in exchange for logged usage data plus their votes as to which of two models returns the most useful completion.

So far the only other independent benchmark result I've seen is for the Aider Polyglot test. This was less impressive:

Codestral 25.01 scored 11% on the aider polyglot benchmark.

62% o1 (high)
48% DeepSeek V3
16% Qwen 2.5 Coder 32B Instruct
11% Codestral 25.01
4% gpt-4o-mini

The new model can be accessed via my llm-mistral plugin using the codestral alias (which maps to codestral-latest on La Plateforme):

llm install llm-mistral
llm keys set mistral
# Paste Mistral API key here
llm -m codestral "JavaScript to reverse an array"

# 13th January 2025, 9:33 pm / mistral, llm, ai-assisted-programming, generative-ai, ai, llms, aider, evals, chatbot-arena

microsoft/phi-4. Here's the official release of Microsoft's Phi-4 LLM, now officially under an MIT license.

A few weeks ago I covered the earlier unofficial versions, where I talked about how the model used synthetic training data in some really interesting ways.

It benchmarks favorably compared to GPT-4o, suggesting this is yet another example of a GPT-4 class model that can run on a good laptop.

The model already has several available community quantizations. I ran the mlx-community/phi-4-4bit one (a 7.7GB download) using mlx-llm like this:

uv run --with 'numpy<2' --with mlx-lm python -c '
from mlx_lm import load, generate

model, tokenizer = load("mlx-community/phi-4-4bit")

prompt = "Generate an SVG of a pelican riding a bicycle"

if tokenizer.chat_template is not None:
    messages = [{"role": "user", "content": prompt}]
    prompt = tokenizer.apply_chat_template(
        messages, add_generation_prompt=True
    )

response = generate(model, tokenizer, prompt=prompt, verbose=True, max_tokens=2048)
print(response)'

Here's what I got back.

Update: The model is now available via Ollama, so you can fetch a 9.1GB model file using ollama run phi4, after which it becomes available via the llm-ollama plugin.

# 8th January 2025, 5:57 pm / phi, generative-ai, ai, microsoft, llms, uv, pelican-riding-a-bicycle, llm, ollama, llm-release, local-llms, mlx

q and qv zsh functions for asking questions of websites and YouTube videos with LLM (via) Spotted these in David Gasquez's zshrc dotfiles: two shell functions that use my LLM tool to answer questions about a website or YouTube video.

Here's how to ask a question of a website:

q https://simonwillison.net/ 'What has Simon written about recently?'

I got back:

Recently, Simon Willison has written about various topics including:

1. Building Python Tools - Exploring one-shot applications using Claude and dependency management with uv.
2. Modern Java Usage - Discussing recent developments in Java that simplify coding.
3. GitHub Copilot Updates - New free tier and features in GitHub Copilot for Vue and VS Code.
4. AI Engagement on Bluesky - Investigating the use of bots to create artificially polite disagreements.
5. OpenAI WebRTC Audio - Demonstrating a new API for real-time audio conversation with models.

It works by constructing a Jina Reader URL to convert that URL to Markdown, then piping that content into LLM along with the question.

The YouTube one is even more fun:

qv 'https://www.youtube.com/watch?v=uRuLgar5XZw' 'what does Simon say about open source?'

It said (about this 72 minute video):

Simon emphasizes that open source has significantly increased productivity in software development. He points out that before open source, developers often had to recreate existing solutions or purchase proprietary software, which often limited customization. The availability of open source projects has made it easier to find and utilize existing code, which he believes is one of the primary reasons for more efficient software development today.

The secret sauce behind that one is the way it uses yt-dlp to extract just the subtitles for the video:

local subtitle_url=$(yt-dlp -q --skip-download --convert-subs srt --write-sub --sub-langs "en" --write-auto-sub --print "requested_subtitles.en.url" "$url")
local content=$(curl -s "$subtitle_url" | sed '/^$/d' | grep -v '^[0-9]*$' | grep -v '\-->' | sed 's/<[^>]*>//g' | tr '\n' ' ')

That first line retrieves a URL to the subtitles in WEBVTT format - I saved a copy of that here. The second line then uses curl to fetch them, then sed and grep to remove the timestamp information, producing this.

# 19th December 2024, 3:42 pm / youtube, llm, jina, zsh, generative-ai, ai, llms

Phi-4 Technical Report (via) Phi-4 is the latest LLM from Microsoft Research. It has 14B parameters and claims to be a big leap forward in the overall Phi series. From Introducing Phi-4: Microsoft’s Newest Small Language Model Specializing in Complex Reasoning:

Phi-4 outperforms comparable and larger models on math related reasoning due to advancements throughout the processes, including the use of high-quality synthetic datasets, curation of high-quality organic data, and post-training innovations. Phi-4 continues to push the frontier of size vs quality.

The model is currently available via Azure AI Foundry. I couldn't figure out how to access it there, but Microsoft are planning to release it via Hugging Face in the next few days. It's not yet clear what license they'll use - hopefully MIT, as used by the previous models in the series.

In the meantime, unofficial GGUF versions have shown up on Hugging Face already. I got one of the matteogeniaccio/phi-4 GGUFs working with my LLM tool and llm-gguf plugin like this:

llm install llm-gguf
llm gguf download-model https://huggingface.co/matteogeniaccio/phi-4/resolve/main/phi-4-Q4_K_M.gguf
llm chat -m gguf/phi-4-Q4_K_M

This downloaded a 8.4GB model file. Here are some initial logged transcripts I gathered from playing around with the model.

An interesting detail I spotted on the Azure AI Foundry page is this:

Limited Scope for Code: Majority of phi-4 training data is based in Python and uses common packages such as typing, math, random, collections, datetime, itertools. If the model generates Python scripts that utilize other packages or scripts in other languages, we strongly recommend users manually verify all API uses.

This leads into the most interesting thing about this model: the way it was trained on synthetic data. The technical report has a lot of detail about this, including this note about why synthetic data can provide better guidance to a model:

Synthetic data as a substantial component of pretraining is becoming increasingly common, and the Phi series of models has consistently emphasized the importance of synthetic data. Rather than serving as a cheap substitute for organic data, synthetic data has several direct advantages over organic data.

Structured and Gradual Learning. In organic datasets, the relationship between tokens is often complex and indirect. Many reasoning steps may be required to connect the current token to the next, making it challenging for the model to learn effectively from next-token prediction. By contrast, each token generated by a language model is by definition predicted by the preceding tokens, making it easier for a model to follow the resulting reasoning patterns.

And this section about their approach for generating that data:

Our approach to generating synthetic data for phi-4 is guided by the following principles:

1. Diversity: The data should comprehensively cover subtopics and skills within each domain. This requires curating diverse seeds from organic sources.
2. Nuance and Complexity: Effective training requires nuanced, non-trivial examples that reflect the complexity and the richness of the domain. Data must go beyond basics to include edge cases and advanced examples.
3. Accuracy: Code should execute correctly, proofs should be valid, and explanations should adhere to established knowledge, etc.
4. Chain-of-Thought: Data should encourage systematic reasoning, teaching the model various approaches to the problems in a step-by-step manner. [...]

We created 50 broad types of synthetic datasets, each one relying on a different set of seeds and different multi-stage prompting procedure, spanning an array of topics, skills, and natures of interaction, accumulating to a total of about 400B unweighted tokens. [...]

Question Datasets: A large set of questions was collected from websites, forums, and Q&A platforms. These questions were then filtered using a plurality-based technique to balance difficulty. Specifically, we generated multiple independent answers for each question and applied majority voting to assess the consistency of responses. We discarded questions where all answers agreed (indicating the question was too easy) or where answers were entirely inconsistent (indicating the question was too difficult or ambiguous). [...]

Creating Question-Answer pairs from Diverse Sources: Another technique we use for seed curation involves leveraging language models to extract question-answer pairs from organic sources such as books, scientific papers, and code.

# 15th December 2024, 11:58 pm / llm, phi, generative-ai, training-data, ai, microsoft, llms, ai-assisted-programming, python, llm-release

Introducing Limbo: A complete rewrite of SQLite in Rust (via) This looks absurdly ambitious:

Our goal is to build a reimplementation of SQLite from scratch, fully compatible at the language and file format level, with the same or higher reliability SQLite is known for, but with full memory safety and on a new, modern architecture.

The Turso team behind it have been maintaining their libSQL fork for two years now, so they're well equipped to take on a challenge of this magnitude.

SQLite is justifiably famous for its meticulous approach to testing. Limbo plans to take an entirely different approach based on "Deterministic Simulation Testing" - a modern technique pioneered by FoundationDB and now spearheaded by Antithesis, the company Turso have been working with on their previous testing projects.

Another bold claim (emphasis mine):

We have both added DST facilities to the core of the database, and partnered with Antithesis to achieve a level of reliability in the database that lives up to SQLite’s reputation.

[...] With DST, we believe we can achieve an even higher degree of robustness than SQLite, since it is easier to simulate unlikely scenarios in a simulator, test years of execution with different event orderings, and upon finding issues, reproduce them 100% reliably.

The two most interesting features that Limbo is planning to offer are first-party WASM support and fully asynchronous I/O:

SQLite itself has a synchronous interface, meaning driver authors who want asynchronous behavior need to have the extra complication of using helper threads. Because SQLite queries tend to be fast, since no network round trips are involved, a lot of those drivers just settle for a synchronous interface. [...]

Limbo is designed to be asynchronous from the ground up. It extends sqlite3_step, the main entry point API to SQLite, to be asynchronous, allowing it to return to the caller if data is not ready to consume immediately.

Datasette provides an async API for executing SQLite queries which is backed by all manner of complex thread management - I would be very interested in a native asyncio Python library for talking to SQLite database files.

I successfully tried out Limbo's Python bindings against a demo SQLite test database using uv like this:

uv run --with pylimbo python
>>> import limbo
>>> conn = limbo.connect("/tmp/demo.db")
>>> cursor = conn.cursor()
>>> print(cursor.execute("select * from foo").fetchall())

It crashed when I tried against a more complex SQLite database that included SQLite FTS tables.

The Python bindings aren't yet documented, so I piped them through LLM and had the new google-exp-1206 model write this initial documentation for me:

files-to-prompt limbo/bindings/python -c | llm -m gemini-exp-1206 -s 'write extensive usage documentation in markdown, including realistic usage examples'

# 10th December 2024, 7:25 pm / rust, sqlite, uv, open-source, python, llm, ai-assisted-programming, documentation, limbo, files-to-prompt

llm-openrouter 0.3. New release of my llm-openrouter plugin, which allows LLM to access models hosted by OpenRouter.

Quoting the release notes:

• Enable image attachments for models that support images. Thanks, Adam Montgomery. #12
• Provide async model access. #15
• Fix documentation to list correct LLM_OPENROUTER_KEY environment variable. #10

# 8th December 2024, 11:56 pm / llm, releases, plugins, generative-ai, ai, llms, openrouter

New Gemini model: gemini-exp-1206. Google's Jeff Dean:

Today’s the one year anniversary of our first Gemini model releases! And it’s never looked better.

Check out our newest release, Gemini-exp-1206, in Google AI Studio and the Gemini API!

I upgraded my llm-gemini plugin to support the new model and released it as version 0.6 - you can install or upgrade it like this:

llm install -U llm-gemini

Running my SVG pelican on a bicycle test prompt:

llm -m gemini-exp-1206 "Generate an SVG of a pelican riding a bicycle"

Provided this result, which is the best I've seen from any model:

Here's the full output - I enjoyed these two pieces of commentary from the model:

<polygon>: Shapes the distinctive pelican beak, with an added line for the lower mandible.
[...]
transform="translate(50, 30)": This attribute on the pelican's <g> tag moves the entire pelican group 50 units to the right and 30 units down, positioning it correctly on the bicycle.

The new model is also currently in top place on the Chatbot Arena.

Update: a delightful bonus, here's what I got from the follow-up prompt:

llm -c "now animate it"

Transcript here.

# 6th December 2024, 6:05 pm / gemini, llm, ai, llms, svg, releases, google, generative-ai, pelican-riding-a-bicycle, llm-release, chatbot-arena

datasette-enrichments-llm. Today's new alpha release is datasette-enrichments-llm, a plugin for Datasette 1.0a+ that provides an enrichment that lets you run prompts against data from one or more column and store the result in another column.

So far it's a light re-implementation of the existing datasette-enrichments-gpt plugin, now using the new llm.get_async_models() method to allow users to select any async-enabled model that has been registered by a plugin - so currently any of the models from OpenAI, Anthropic, Gemini or Mistral via their respective plugins.

Still plenty to do on this one. Next step is to integrate it with datasette-llm-usage and use it to drive a design-complete stable version of that.

# 5th December 2024, 11:46 pm / llm, plugins, ai, llms, enrichments, releases, datasette, generative-ai, projects

datasette-queries. I released the first alpha of a new plugin to replace the crusty old datasette-saved-queries. This one adds a new UI element to the top of the query results page with an expandable form for saving the query as a new canned query:

It's my first plugin to depend on LLM and datasette-llm-usage - it uses GPT-4o mini to power an optional "Suggest title and description" button, labeled with the becoming-standard ✨ sparkles emoji to indicate an LLM-powered feature.

I intend to expand this to work across multiple models as I continue to iterate on llm-datasette-usage to better support those kinds of patterns.

For the moment though each suggested title and description call costs about 250 input tokens and 50 output tokens, which against GPT-4o mini adds up to 0.0067 cents.

# 3rd December 2024, 11:59 pm / projects, releases, datasette, plugins, llm, generative-ai, openai, ai, llms