Post

mattsayar.comI didn't want to pay for a newsletter email service so I built my ownI wrote a whole post about setting up free newsletters for your website but it was all a lie. Sure, after your free trial runs out, you can still technically send newsletters for free. Manually. Painf...

I literally just put all all your advice into practice for my latest project. I even quoted you! mattsayar.com/i-didnt-want...

Max Milne

@maxmilne.bsky.social

Thank you for your continuously ongoing generosity.

Matthias Lübken

@luebken.bsky.social

@simonwillison.net great post. In your process, you explicitly put human in the loop. Do you think that is sufficient to gain intuition and experience? Or do we need to adopt some new practices? e.g. using LLMs to quiz us?

Joyce Park

@troutgirl.bsky.social

📌

Dave MacLean

@daveatcogs.bsky.social

Thanks Simon — will take a look at this when I am back in the office!

Miska Knapek

@miskaknapek.bsky.social

Thank you - very good tips!

tools.simonwillison.nettools.simonwillison.net colophon

It includes detailed examples, including the full Claude Code process I used to build this new Colophon page, which presents the Git commit histories for each of my collection of LLM-assisted web tools in one place tools.simonwillison.net/colophon

simonwillison.netMy tools colophon now has AI-generated descriptionsThe [/colophon](https://tools.simonwillison.net/colophon) page on my tools site lists all 78 of my tools along with their commit histories, including links to prompting transcripts. I wrote about [how...

13 Mar 2025

Colophon update: I added automated documentation for all 78 of my tools, written by piping the HTML through Claude 3.7 Sonnet I was hesitant to do this at first but the utility of the resulting explanations convinced me it was worthwhile More details here: simonwillison.net/2025/Mar/13/...

I decided the descriptions it wrote were too long, so I added "Keep it to 2-3 sentences" to the prompt and rebuilt them all to be more concise: github.com/simonw/tools...

Matt Sayar

@mattsayar.com

> It cost about $1.08 in Claude credits to document all 78 tools Does this imply you used Claude Code? Or your llm CLI

adpirz.bsky.social

@adpirz.bsky.social

I’ve been following your stuff for a while now and your articles continue to be the most measured and grounded-in-real-world-experience takes when it comes to practical LLM applications. No hype, no doom, no dismissal. Thanks for being a standard bearer here.

Robert Atkins

@ratkins.net

Thank you for writing this up!

📌

@gc-victor.bsky.social

I'm surprised that you aren't using system prompts

simonwillison.netBuilding Python tools with a one-shot prompt using uv run and Claude ProjectsI’ve written a lot about how I’ve been using Claude to build one-shot HTML+JavaScript applications via Claude Artifacts. I recently started using a similar pattern to create one-shot Python utilities,...

I use custom instructions in Claude projects for a few things simonwillison.net/2024/Dec/19/...

Víctor García

@gc-victor.bsky.social

Oh, great! And have you tried more general system prompts to guide the conversation and output in a structured way? Like returning as output a diff, like what some code assistants do