Claude Skills are awesome, maybe a bigger deal than MCP by Simon Willison

Skills are Markdown with a tiny bit of YAML metadata and some optional scripts in whatever you can make executable in the environment. They feel a lot closer to the spirit of LLMs - throw in some text and let the model figure it out.

Here’s the learn documentation.

It’s a simple feature. The bunch of things Anthropic has announced since the past one month while I’ve been on the ChatGPT train is staggering.

I am tempted to go back. The only thing ChatGPT has right now is the web ui for codex. This was ot would be free till 20th, after which the web usage will count toward the overall limits.

I think it makes sense to me to go back to Claude and try that out.

Superpowers: How I'm using coding agents in October 2025

Skills are what give your agents Superpowers.

The first time they really popped up on my radar was a few weeks ago when Anthropic rolled out improved Office document creation. When the feature rolled out, I went poking around a bit – I asked Claude to tell me all about its new skills. And it was only too happy to dish.

This is how Claude creates docs with that new feature that came out.

These are basically markdown documents that Claude reads to do things a certain way.

This post is full of so much interesting stuff. Like Claude can use this to read a book, or doc, or repo and teach itself new skills.

This is how to install it.

You'll need Claude Code 2.0.13 or so. Fire it up and then run:

/plugin marketplace add obra/superpowers-marketplace
/plugin install superpowers@superpowers-marketplace 

Quit and restart claude and you should be good to go.

Claude Sonnet 4.5 is probably the “best coding model in the world” (at least for now) by Simon Willison

My initial impressions were that it felt like a better model for code than GPT-5-Codex, which has been my preferred coding model since it launched a few weeks ago. This space moves so fast - Gemini 3 is rumored to land soon so who knows how long Sonnet 4.5 will continue to hold the "best coding model" crown.

I wanted to try out chatGPT before committing to Claude for longer term. I did do that now. It is good at a few things, like, the web agent feature, which I’ve used extensively over the past couple of weeks.

OpenAI also released the codex model around that time. For coding tasks it has been better in my experience than Claude, hardly making any mistakes. I had to prompt it to change something a couple of times out of almost fifty or so code changes.

The 4.5 release is supposed to be better.

ChatGPT was worse at creating draft CVs though. I was looking to go back to Claude for this reason alone. I think I will now.

Microsoft favors Anthropic over OpenAI for Visual Studio Code by Tom Warren

It’s a tacit admission from Microsoft that the software maker is favoring Anthropic’s AI models over OpenAI’s latest GPT-5 models for coding and development. Sources familiar with Microsoft’s developer plans tell me that the company has been instructing its own developers to use Claude Sonnet 4 in recent months.

I have been in this boat myself. I was using Claude (Pro) this past month.

I am mostly happy with it. I was about to buy yearly subscription for it, there are same savings to it.

But then, OpenAI updated codex with a new release optimised for coding. And so I thought, before pulling the trigger and subscribing for a year let me give ChatGPT a go as well for a month.

Also, I am missing cursor agents. And codex does have agents. That might prove to be useful.

What I think about when I think about Claude Code

Then I say: "please look over the 30-40 most recent files in the blog posts folder and - concentrating on the ones that aren’t like finished posts (because I will have published those) - give me half a dozen ideas of what to write a blog post about today"

I don’t use it to do any actual writing. I prefer my words to be my own. But it’s neat to riff over my own notes like this.

I have started using Claude Code today because my Cursor Pro subscription ended today. For the limited time I’ve used it today, I like the flow of the thing.

I enjoyed asking Agent to do something from my phone while I was out anywhere. That I would miss.

The above sounds like a good idea, for using my Obsidian vault a bit more. I had another idea of course to fix metadata in my obsidian vault. I would soon.

My review of Claude’s new Code Interpreter, released under a very confusing name by Simon Willison

Claude can now write and execute custom Python (and Node.js) code in a server-side sandbox and use it to process and analyze data.

In a particularly egregious example of AI companies being terrible at naming features, the official name for this one really does appear to be Upgraded file creation and analysis. Sigh.

This feature is not available for Pro users yet. I don’t have it.

Claude can access reminders, maps and calendar now. There was a default prompt where it checked my calendar and added a 2 hr focus session including a reminder to take my headphones.

It worked fine.

This is great. My one use case for this would be to ask Claude to add calendar invites based on pictures. It did it partly already, using screenshots and creating events. Now it can add them to the calendar directly. Progress!!

Reverse engineering some updates to Claude

New on mobile: Draft and send emails, messages, and calendar invites directly from the Claude app.
@AnthropicAI, 30th July 2025

Claude artifacts are now even better.
Upload PDFs, images, code files, and more to AI-powered apps that work with your data.
@AnthropicAI, 31st July 2025

These are useful features, at least the first one. OpenAI announced study mode in ChatGPT recently which was similarly useful. It’s good to have these stream of new features which are just system prompts though Anthropic has created new tools for these.

Apple shows up a helpful add in calendar in front of emails which have an invite or appointment of any sort, but that is done if it’s obvious, in the body text, for example. They could enhance it with adding the option in the camera app directly like they do with the transcription option where you can copy any text in any photo, or directly from the camera app. They could add an option to find any invites in pdfs for example.

Google Lens allows for that.