Latest / In The Loop / Claude Skills: How to use them, why they are important & what they are.
Transcript
- 0:00Skills are, in my view, one of the most important and probably
- 0:04one of the most underused features in the.
- 0:07Cloud ecosystem right now. And even arguably beyond the
- 0:11cloud ecosystem, if you're using cloud for anything serious, you
- 0:15probably hit. This problem.
- 0:17You've got it working exactly how you want it for a specific
- 0:20task that has a perfect output, and then the next time you have
- 0:23a conversation it's just begotten everything.
- 0:26You could copy and paste instructions into the chat every
- 0:28time, and many people do this, but that doesn't scale.
- 0:32GPTS or clawed projects help, but they're not the same as it
- 0:37understanding a process for a specific task, and they fill up
- 0:40the context window far too quickly.
- 0:43Because you preload them. Full of so much information.
- 0:46To it has the information it needs to help you do a task.
- 0:49And so you're constantly running out of space in a conversation
- 0:52and having to start a new thread.
- 0:53The solution is skills. A skill is a set of instructions
- 0:56you write once give to claw. Encode your process and your
- 0:59preferences, and today we're going to go deep on them.
- 1:03We're going to go into the actual principles of context
- 1:07engineering and why skills are so important.
- 1:09The exact anatomy of a skill file with real examples that you
- 1:13can use today and how you can make them and how you can chain
- 1:16different ones together and where to.
- 1:18Find skills and install them. How they fit alongside MCPS.
- 1:22Or plug insurance. And we shouldn't.
- 1:24Even bother using them at all, this is in the loop.
- 1:26With Jack Horton. Hope you enjoyed the show.
- 1:40Before we get into what skills are, I think it's probably worth
- 1:44understanding the problem they were built to solve and kind of
- 1:47what they consist of. What is a skill?
- 1:50Because once you understand that, I think everything will
- 1:51start to really fall into. Place so throughout. 2025 AI
- 1:55coding agents were getting dramatically better and better.
- 1:59Core code could suddenly, you know, build really complex
- 2:03systems. They could.
- 2:03Read an entire file system. They could.
- 2:06Interact with Git. They can run tests, they can
- 2:08deploy things, and the capability was obviously there
- 2:11to do really cool stuff. But what most people found is
- 2:14they hit a wall, and that wall really was the context window.
- 2:17We've talked about context engineering before in July 2025,
- 2:21and it's the same for even those that are not using core code.
- 2:24The amount of times you just run out of space and this happens
- 2:27with GPTS. And core projects.
- 2:29And what's actually happening here is that every time you want
- 2:31Core to obviously know something.
- 2:32Whether? It was your, I don't know,
- 2:34teams, coding standards, how an API works, the context of the
- 2:38market or the business you're working in.
- 2:40You basically be pasting lots of information to the chat, which
- 2:43essentially crams. Everything into the.
- 2:46LLM System prompt which is this big long prompt.
- 2:49It gets sent to an LLM that defines, you know, its.
- 2:52Purpose. How it should behave?
- 2:53What it should? Do and as agents and LLMS get
- 2:57more powerful, the list of things that.
- 3:00Is included. In that system.
- 3:01Prompt is always growing, so there's more instructions,
- 3:04there's more tools so the integrations it can use.
- 3:06So that system prompt is just ballooning.
- 3:08And the problem with that is that the context windows are
- 3:10finite. The more you step in there, the
- 3:12worse the agent starts to perform.
- 3:14It gets slower and more expensive, less reliable, and
- 3:18there's a real tension between giving an agent you know as much
- 3:21information as possible and making it able to execute
- 3:25consistently well. And this insight is what led to
- 3:28skills. Agents don't need all of that
- 3:31knowledge and information all of the time.
- 3:34What they need is the right information, the right ability
- 3:37to run a process, or awareness of a process at the perfect
- 3:40moment. And so in in about late October
- 3:422025, Anthropic published a blog called Equipping Agents for the
- 3:47Real World. With agent skills.
- 3:49And they framed. It kind of like this they.
- 3:50Said Claude is really powerful, but real work requires
- 3:53procedural information and just organizational contacts.
- 3:57And as agents become more and more capable, we need more
- 4:00composable, scalable and portable ways to equip them with
- 4:03that domain specific expertise. And that's what led to agent
- 4:08skills, which essentially are an organized set of folders.
- 4:11Full of instructions and resources that help agents.
- 4:15To basically discover and load the right thing at the right
- 4:17time and I think the key phrase. Here is dynamically.
- 4:20So these skills. Aren't always there for.
- 4:24The agent, they're not sitting in the context window taking up
- 4:27space. They only get loaded when
- 4:29they're relevant and stay out of the way when they're not.
- 4:31And that's A, and that's a fundamental.
- 4:34Design. Principle of any modern day
- 4:35agent. Really you know and topic is a
- 4:37specific. Name for it.
- 4:38That's been adopted. Everywhere.
- 4:40Which is called. Progressive disclosure so you
- 4:43progressively. Disclose more information to the
- 4:46agent needs. Only.
- 4:47Actually when it needs it. So this progressive disclosure
- 4:50happens. In three layers.
- 4:51Layer one when Claude starts a. Session it basically preloads.
- 4:55Just the name. And the description of the
- 4:58skills. So not the full set of
- 5:00instructions, just a one line summary.
- 5:02You know, maybe 100 tokens per skill.
- 5:04So again, a few words. This makes it possible for the
- 5:07agent to know, I guess, what is available to it.
- 5:10We just talked about this before, the tools that were
- 5:12available to this agent and therefore it's cheap enough to
- 5:15always have those small. Descriptions loaded.
- 5:17Then you've got layer 2 when when essentially Claude
- 5:20encounters a task and recognises that one of those descriptions
- 5:23is relevant. It then loads that full skill
- 5:25file and as a result it will have the complete.
- 5:28Rules and instructions that you. Create for it, but only does it
- 5:31for that specific skill, not all of the skills.
- 5:34So again, you could give it dirty.
- 5:36Skills or tools? And it will only.
- 5:39Use one of them so again. Protecting that context window,
- 5:42and then you've got layer three. If the skill MD file references
- 5:47other files in the folder of templates or reference docs or
- 5:51scripts, code will actually be able to navigate to those as
- 5:54needed. It doesn't read everything
- 5:57upfront, it follows it for references.
- 5:59So if a process that it's following says use this extra
- 6:03doc, it will then go and find that extra dock.
- 6:06It won't then load every single skill.
- 6:07Think about it like a set. Of instructions.
- 6:09Basically layer 1 is like the table of contents, layer 2 is
- 6:12that you know, relevant chapter I guess and layer. 3 is the
- 6:16appendix. You don't need the whole thing
- 6:17every time. So now you understand, you know,
- 6:19why we have skills, why they're important and what they're kind
- 6:22of made-up of. I think then let's build a skill
- 6:25together. And I think the walkthrough.
- 6:27Of this. Helps you.
- 6:28Really understand what a skill is beyond just me using.
- 6:31Kind of abstract words, instructions, because I think
- 6:34it's really important to. Understand the mechanics.
- 6:35And the specifics here. So if we build 1 together,
- 6:37right, you have to picture this. So let's say you write a team
- 6:41update every single Friday, and every time you ask Claude for
- 6:45help with this, you end up giving it basically the same set
- 6:47of prompts every single time. You know, keep it under 300
- 6:49words. Lead with wins.
- 6:51Plain language, no weird AI, slop language.
- 6:55End with the blockers and every few.
- 6:57Weeks Cloud does something annoying.
- 6:58Maybe it allowed a random sign off or use the wrong language
- 7:01again and you have to then. Correct it.
- 7:03So here's how you would solve that with skills.
- 7:21Now before I get into this, it's.
- 7:22This is a few bits of a process here, and it's also important to
- 7:25note that on all the cloud interfaces you should have an
- 7:28option of just either having a skills creator.
- 7:31Or just telling. Claude, create all of this
- 7:34process as a skill and review it and collaborate with it.
- 7:36Collaborate on this skill with me.
- 7:39So you can actually tell it to turn things you've been working
- 7:41on into a skill, then review it. But I think for the purposes of
- 7:46this discussion, it's still important to understand how to
- 7:48create one because it'll give you an in depth understanding of
- 7:51what the heck this thing is. So step one would be create a
- 7:53new. Folder on the computer, call it
- 7:54weekly update or tell Claude to create a folder and call it
- 7:59weekly update. Tell it to organise.
- 8:01It as it. Sees fit or it.
- 8:03Makes sense. Remember the core Co work
- 8:05episode we've done I think about 5 weeks back?
- 8:08If you haven't listened to that, I'd recommend also listening to
- 8:11that alongside this episode. Anyway, Step 2 would be to go
- 8:16inside that folder, create a new.
- 8:17File and it's a text file, you name it skill dot MD.
- 8:20All caps for skill then dot MD. For the extension.
- 8:23Step three. You open that file and at the
- 8:25very top you're going to give. Cloud 2 piece of information,
- 8:28you name the name of the skill and a one line simple
- 8:31description of what it does and that's.
- 8:33It below that you write actual. Instructions for example.
- 8:37Write a concise weekly team update following our style of
- 8:40format. Use when the user asks for help
- 8:43with a weekly update or. Stand up summary or team status
- 8:46report. Now notice that description.
- 8:47I've included a few trigger phrases.
- 8:49Weekly update stand up. Summary team status report.
- 8:54So this gives Claude multiple ways to recognize when this
- 8:56skill is needed. So if I then in a conversation
- 8:59say I am writing this team status report, it would then
- 9:03pull up and use this. This tool or this this?
- 9:06Skill Step 4, you would then write the body, which is the
- 9:08instructions. So you'd call it a heading
- 9:11weekly team update format. And then when asked to write or
- 9:14help with a weekly team update, all of these rules and then you
- 9:18set the rules out. You can also have areas called
- 9:20structure, you know open with a section called wins of the.
- 9:22Week. Containing 2.
- 9:24To four bullet. Points of complete work.
- 9:26You could have tone so don't use AI jargon and weird corporate
- 9:30pillar. Keep it in first person.
- 9:33You say LEMP, keep it under 300 words and then add a section
- 9:37called gotchas. So never use phrases like
- 9:40moving. Forward or synergy or circle?
- 9:42Back don't sign off saying kind regard because this isn't an
- 9:46e-mail. This is going into a Slack
- 9:48channel. And that's what a skill file is.
- 9:51And the gotcha section is something Anthropic specific
- 9:53calls out as one of the highest signal content in any set of
- 9:56skills, One of the. Claude.
- 9:58Code team members actually wrote that in a in a blog post that
- 10:02the highest value thing you could possibly do is build up a
- 10:05gotcha section over time so every time Claude makes a
- 10:08mistake you can add to it. The skill becomes a living
- 10:11document that essentially accumulates your hard won
- 10:13knowledge about what goes wrong and how to prevent it.
- 10:16So every time you're having a conversation with Claude, say I
- 10:19want you to update the skill dot MD file for XYZ skill with.
- 10:23These new gotchas and. Again, you're just building up.
- 10:26Constant information and knowledge on this.
- 10:28And then finally, obviously you. Save the file.
- 10:30So that means you've now got a. Folder called weekly.
- 10:32Update with a file called skill dot MD inside it.
- 10:35You can then install it. And this depends on how you use
- 10:37calls. If you're using cloud dot AI, so
- 10:39the web interface, you zip that folder, not the file, the actual
- 10:43folder itself. Right click the folder, compress
- 10:46it into a zip and then go to cloud AI.
- 10:48And if you go into settings, you can actually.
- 10:51Go into customize and then skills and then you can upload
- 10:54the skill using that zip file. If you are using the web
- 10:56interface, which I recommend no one do, you should be using the
- 11:00Co work interface or core code. But if you are using that you
- 11:03need to go and turn on code execution and file creation
- 11:06skills. Kind of need that to function if
- 11:08you're using. The core code interface.
- 11:10It's really easy, you just tell it to do it and it will bash
- 11:13command it. It'll just set it up for you now
- 11:15if you are. Writing Organization.
- 11:16Wide skills you'll probably need to speak to your admin, but you
- 11:19can even tell it to make this a personal skill or a team wide
- 11:23skill if you're using clouds COA which is the.
- 11:26Desktop interface skills can come bundled in plug insurance
- 11:29or just upload them through the same settings panel.
- 11:32As Claude dot. AI as I said Claude Co work is
- 11:35the same agent as Claude code so.
- 11:37You can basically ask. It to just do it for you.
- 11:39And they've just released a new feature for most people called
- 11:42the Skills Creator, which just helps you create a.
- 11:44Skill. So yeah, once you've done that,
- 11:46every time you start a new conversation, Claude sees all
- 11:49the different skills that it's got available to it and it's
- 11:52descriptions. That's that layer one.
- 11:54It costs almost nothing in context window and capacity and
- 11:58then when you say something like here are my.
- 12:00Notes for this week's. You know, write up our update,
- 12:03it will then load up that skill and it will work.
- 12:05Now really quick, really quick note here.
- 12:08It could probably be quite attractive to start turning
- 12:10everything into skills when that's just not necessary.
- 12:14So if it's a one off task, just use prompts.
- 12:16If it's a repeatable task that you do a.
- 12:17Lot or you need other. Team members to fulfill.
- 12:20Then you can make a skill. And when you write.
- 12:22The skills. There's a trap.
- 12:24You don't need to. Reinstate what Claude as a
- 12:26baseline model already knows. Anthropics guidance on this is
- 12:30really really direct, so don't tell it how to write Python
- 12:33because it knows. How to write Python?
- 12:35Don't tell it what good code looks like in general, tell it
- 12:37what good code looks like in your specific code base.
- 12:40So again, it's about making it contextual and writing it out
- 12:44your process that you want. This thing to follow and then
- 12:46once you've built a skill, test it.
- 12:48Don't just use it once and go, oh, that was good.
- 12:50Use the skill. Creator's Evaluation.
- 12:51Tools run the skill against different prompts.
- 12:53And then don't. Make it too prescriptive so
- 12:56there's a difference between. A skill and a.
- 12:57Template templates. Break the moment.
- 13:01The situation changes. We talked about this last week
- 13:03and you'll notice this is all about reliability.
- 13:06And consistency. If you write something that is
- 13:08if this, then that. It's.
- 13:10Going to be. Quite rigid.
- 13:12And therefore. If you need to be flexible, it's
- 13:15not going to work in the same way.
- 13:16So again, Quad and Anthropica are very clear here.
- 13:20It's about a skill. Not a template.
- 13:22So yeah, that that's how to make a skill and when not to make a
- 13:25skill. But I also wanted to talk about
- 13:27how to make skills extremely powerful.
- 13:30So if you imagine, that's kind of like getting started.
- 13:33This is now moving into. Advanced thinking, not because
- 13:36it's super complex, but because it makes such an extra impact on
- 13:40how you work. And that's skill chains.
- 13:56So yeah, the next level is when skills start working together,
- 13:59and I'm going to give you an example of four skills that feed
- 14:01into each other to form a complete development process
- 14:04from a vague idea all the way. Through to tested ship code.
- 14:07And it came from a developer called Map Poco.
- 14:10And you might be thinking, oh, but I'm not a developer now.
- 14:13I'll also provide a couple of extra examples here about.
- 14:16Non developer or product focused tasks.
- 14:18So the first skill is called. Grooming.
- 14:21And I'll read it out in full because I think it's important
- 14:23to hear just how simple a skill can be.
- 14:26The entire skill body is 3 sentences.
- 14:28Interview me. Relentless about every.
- 14:30Aspect of this. Plan until we.
- 14:31Reach a shared. Understanding.
- 14:33Walk down every single branch. Of the decision.
- 14:35Tree resolve any dependencies between decisions 1 by 1.
- 14:39And finally, if a question can be answered by exploring the
- 14:42code base, explore the code base instead, so.
- 14:44Three sentences and that's the whole thing.
- 14:46And he said Sessions where I called asked him 30-40 fifty
- 14:49questions from that tiny skill before it was satisfied that
- 14:53they understood the problem. And you might be thinking, gosh,
- 14:56that's a lot of typing. But if you've not got super.
- 14:59Wispy yet? I recommend you to go and pay
- 15:02just a few pounds a month. I think they.
- 15:04Also have a pre tier but it's just an amazing basically voice
- 15:08tool that you can press a shortcut, it appears and when
- 15:10you're finished speaking the text appears in any text box.
- 15:14It makes my life infinitely easier.
- 15:16But anyway. And then?
- 15:17Once the grilling. Is done.
- 15:18It'll invoke a second skill, write a PRD.
- 15:21So this is a structured multi step skill and apid is a
- 15:24product. Requirement document says.
- 15:27What people in product write. Before they build something
- 15:31so-called. Will then start to ask the user
- 15:32for a detailed. Description it'll explore.
- 15:34The repo to verify any. Assertions it will interview.
- 15:38And once all this is done, this. Document's written.
- 15:40It will also submit this as a GitHub issue, so actually raises
- 15:44it in the system of record to track work.
- 15:46And So what comes out on the other end is a ticket or.
- 15:49An item of a a task to be done. With a full document, with a
- 15:53problem statement, a proposed solution, detailed stories.
- 15:56In the right format, implementation decisions.
- 15:59And then it will. Trigger 1/3 skill called the PRD
- 16:01to issues. That takes the document and
- 16:03breaks it. Into a series of individual.
- 16:05Tasks each task. Is essentially A deliverable
- 16:08piece of work that the team can work on.
- 16:10For example, it will start with. What is most important to start
- 16:13on? Usually the things with the
- 16:15highest risk to a project. The skill will also establish.
- 16:18Blocking relationships between. Tasks.
- 16:20So task 3 might depend on task one, but task 2 might be
- 16:23independent and should be therefore picked up in parallel.
- 16:25So this is really useful if you're running many different
- 16:28agents at the same time. For example, this is what a
- 16:30product manager and a developer has to be.
- 16:31Finally, when it's time to implement, there's a Test Driven
- 16:34Development skill. So basically is a process that
- 16:37enforces and confirms with the developer what interface.
- 16:40Changes are going to be needed. Agreed.
- 16:42Therefore, which behaviors we have to test and then enter a
- 16:44loop and you can't? Have that thing finished until
- 16:47it achieves those sets of behaviours that you were looking
- 16:50to. Actually achieve so.
- 16:52That's a very. Product centric example that the
- 16:54take away here for non developers as well is that.
- 16:56This principle. Of chaining works regardless of
- 16:59domain, so and even that process.
- 17:01We went through. You could build a research
- 17:03brief. Skill that feeds into a draft.
- 17:04Article skill that feeds into a format for newsletter skill.
- 17:08The exact same architecture, discovery, planning, execution,
- 17:13each skill picking up where the last one left on.
- 17:15And this mechanism is domain agnostic.
- 17:17The instructions inside is what makes.
- 17:20It specific to your work. Now you might be thinking, gosh,
- 17:22it's really exciting, but maybe a lot to get.
- 17:25Started on here. Well, there are places for you
- 17:28to go find other skills, bring them in and get inspiration.
- 17:32I will have one warning. Which is obviously when you're
- 17:35downloading things from the Internet that are just very
- 17:38public and inside a community. It does present risk.
- 17:41So if you bring that straight into your.
- 17:44Your environment that you're doing coding from or whatever it
- 17:46might. Be.
- 17:47You need to make sure that you're going and getting trusted
- 17:50verified sources. So just just a.
- 17:52A preface that. Super popular ones, probably
- 17:54more say, but going on random websites and finding skills and
- 17:57downloading them. Will always present some risk.
- 18:00So anyway, Anthropic has got an entire skill set of a skill
- 18:03library, should I say, on the GitHub reposogithub.com
- 18:07Anthropic. Skills.
- 18:09You know there's skills by creating word docs, excel
- 18:11spreadsheets. PowerPoint presentations.
- 18:13PDS. Beyond Anthropic, the community
- 18:15is massive now. There are curated collections on
- 18:18GitHub with 10s of thousands of stars.
- 18:20There are directories listing. Thousands of community skills
- 18:23and there's even growing ecosystems of plug in.
- 18:26Particularly in core Co work and for those that don't understand
- 18:30the difference. Between skills, MCPS and plug
- 18:32insurance. There's often a lot of confusion
- 18:34here. Think of it in three layers.
- 18:37Skills are the knowledge layer, so they tell Claude how to do a
- 18:39thing. So a.
- 18:40Process or a preference. A skill doesn't connect Claude
- 18:43to anything in the external world.
- 18:45Just makes it smarter about a. Particular task MCPS.
- 18:48To model context protocol are the connection layer.
- 18:52They let Claude reach out into your.
- 18:54Slack your GitHub repo. Your CRM your.
- 18:57Calendar. And plug insurance are basically
- 18:59the. Packaging layer.
- 19:01A plug in bundles skills, MCPS, other resources together that
- 19:05you can just then install in a single gap.
- 19:08So instead of separately configuring a Slack MCP, writing
- 19:11a skill for how your team uses Slack, and then setting all that
- 19:14up manually, you can just. Create a plug in that does all
- 19:16of that together. Skills of the brain, MCPS of the
- 19:19hands and. Plug insurance the toolbox, and
- 19:21the best thing here is that skills aren't just an.
- 19:23Anthropic thing. It was published.
- 19:24As an open standard in December 2020.
- 19:26Five and. Since then it's been adopted by
- 19:28loads of tools like Open AI codecs, GitHub Copilot VS Co
- 19:33Cursor, Gemini. They're all supporting the same
- 19:35format. It's one of the fundamental ways
- 19:37that would build a. Lot of new.
- 19:38Functionality now. On our product.
- 19:40Aligning ourselves with that ecosystem.
- 19:59So yeah, let's conclude for today's episode because here's
- 20:02the bigger picture. We're in this massive
- 20:04transition. From using AI.
- 20:06As a conversation. To using.
- 20:07It as a library of reliable. Repeated.
- 20:10Capabilities and every time you figure out how to get one of
- 20:13these things, these systems, these large language models to
- 20:16do something well, you can capture that knowledge.
- 20:19So it compounds over time, and that's what skills are
- 20:22compounding information. That you and your team can
- 20:25leverage over time. Skills turn.
- 20:28One person's expertise into everyone's.
- 20:30Capability your best. Engineers review process
- 20:33becomes. A skill the whole team can run.
- 20:36Your best writer can be the foundation to how every person
- 20:40in your company writes content. So if there's one thing to take
- 20:42from this episode, it's this The next time you find yourself
- 20:45giving called the same instructions the third time in a
- 20:48row, just stop and write skill. We'll look to link everything
- 20:52into the show notes. You know, documentation skills
- 20:54repos basically as much as. Possible for you to.
- 20:57Get started on. Skills anyway.
- 21:00That's it for me. I hope you enjoyed the episodes.
- 21:04And I'll see you next week.