Karo Zieminski spent nine days breaking Claude Cowork before writing this guide:

I’ve seen enough of shallow tutorials that simply rephrase the official docs to know I wanted to do something different. So I rebuilt some of my workflows from scratch, tracked what failed, measured what saved time, and mapped 56 practical tips into the resource I wish existed when I started.

I appreciate her methodical breakdown of the app, especially when to use which flavor of Claude, which for me TBH, has been an issue.

Zieminski’s nice breakdown of the differences between Claude Chat, Cowork, and Code.

The guide barely talks about prompting. It’s almost entirely about the pre-work: dedicated folder structures, global instructions via CLAUDE.md, chunked skills, delegation patterns that define end-states instead of steps. The distinction Karo draws between Chat skills and Cowork skills:

Skills in Chat were useful. Skills in Cowork are operational. They shape autonomous work. Your brand guidelines skill doesn’t just influence a reply. It governs every file Claude creates. Your writing guidelines skill doesn’t just shape a draft. It governs every article Claude writes autonomously.

Zieminski on skill architecture:

Chunk your skills instead of building one giant skill that tries to handle everything. I’ve tested both approaches and the results from one giant skill were much worse. For example, I use three separate writing skills instead of one: an overall voice skill, a corporate writing skill, and a newsletter writing skill. Each handles its own context. Claude never confuses who I’m writing for.

If you’re already using Claude Cowork or just Cowork curious, bookmark this one.

Thariq Shehzad, on the Claude Code team at Anthropic, has switched from markdown to HTML as his default agent output format. The reasoning is more honest than a format-war argument would suggest, because it’s about what humans will actually read. He opens by acknowledging what markdown was for:

Markdown has become the dominant file format used by agents to communicate with us. It’s simple, portable, has some rich text capability and is easy for you to edit. Claude has even gotten surprisingly good at using ASCII to make diagrams inside of markdown files. But as agents have become more and more powerful, I have felt that markdown has become a restricting format.

Then the pivot:

As Claude is able to do more complex work, it is also writing larger and larger specs and plans. In practice, I’ve found I tend to not actually read more than a 100-line markdown file, and I certainly am not able to get anyone else in my organization to read it. But HTML documents are much easier to read, Claude can organize the structure visually to be ideal to navigate with tabs, illustrations, links, etc.

When the spec gets long enough that you stop reading it, you’ve quietly moved from review to rubber-stamp. Shehzad’s answer isn’t to ask Claude for shorter specs. It’s to make the artifact something a human will actually open, scroll, and share. A controllable, shareable artifact is most of what made personal computing legible in the first place; HTML is the format that already does it.

He puts the trade-off honestly when the obvious objection comes up:

While markdown often uses fewer tokens, I’ve found that the added expressiveness of HTML and the much higher likelihood of me reading it means I get overall better output. With the 1MM context window in Opus 4.7, the increased token usage is not really noticeable in the context window.

And the close is the real argument:

The real reason I use HTML is that I feel much more in the loop with Claude. I had begun to fear that because I had stopped reading plans in depth I would simply have to leave Claude to make its choices. But I am happy to say instead that I feel more in the loop than ever before when using HTML.

Claude skills are structured markdown files that tell Claude how to handle a specific type of task. It is—as the name suggests—a new skill Claude or any AI agent can “learn.” Each one defines a role for Claude to adopt, the inputs it needs, a step-by-step workflow, and a quality bar for the output. You can build them for anything—research synthesis, writing, code review, design critique. Once loaded, Claude follows the workflow instead of improvising.

Nick Babich, writing for UX Planet, put together 10 skills aimed at product designers. The three I’d reach for first are the UX Heuristic Review, the Design Critique Partner, and the Competitor Analysis Generator. All three give a solo designer a structured second opinion on demand: a heuristic eval against Nielsen’s 10, a senior-level design critique, or a competitive feature matrix.

Babich’s skill format is clean and worth studying even if you end up building your own from scratch. (Hint: or use Claude Code to write its own skills.)

Cat Wu, Anthropic’s Head of Product for Claude Code, describes the hiring filter on her team in her interview with Lenny Rachitsky:

I think all of the roles are merging. PMs are doing some engineering work. Engineers are doing PM work. Designers are PMing and also landing code. You can either hire a lot more engineers who have great product taste, or you can keep your engineering hiring the same and hire a lot more PMs to help guide some of their work. On our team, we’re pretty focused on hiring engineers with great product taste. This way we can reduce the amount of overhead for shipping any product. Like there are many engineers on our team who are fully able to end to end go from see user feedback on Twitter through to like ship a product at the end of the week with almost no product involvement. And this, I think, is actually like the most efficient way to ship something. So I think like engineer and PM are kind of overlapping and you will get a lot of benefit from having more of either. I think product taste is still a very rare skill to have and we’ll pretty much hire anyone who we feel has demonstrated this strongly.

This is what the Full Stack Builder pattern looks like as a hiring filter. The headline is the merging of roles. Wu’s own background says where the bench comes from:

Yeah, I was an engineer for many years. I was then a VC very briefly before joining Anthropic. And actually almost all the PMs on our team have either been engineers or ship code here on Claude Code. And so that’s one of the things that I think helps build trust with the team and also just enables us to move a lot faster. And then actually our designers also have been front-end engineers before.

So to be clear, Wu doesn’t say that the roles have merged, but what she’s describing is the continued blurring of lines.