Create Custom Skills in AI for Repeat Tasks

A visiting friend taught me how to create a custom skill in AI. It was an eye-opener.

Prompt engineering was a thing when AI chatbots first started. The quality of AI responses depended on what you included in your prompt. Companies reportedly paid as much as $300k in annual salary for prompt engineer positions.

AI has largely taken over that role. You can ask AI to write those prompts for itself. Or you can ask one AI to write prompts for another AI. The prompts that AI writes are often more detailed and effective than the prompts you write.

A custom skill goes along these lines. You can ask AI to do something and go back and forth a few rounds to fine-tune it, or you can ask AI to create instructions for itself on how to do that task. The result is a reusable custom skill. You trigger the saved skill when you need to perform the same task again. AI reads the instructions and does it the way you wanted.

Skill Examples

I’ve created several custom skills so far. Here are two examples:

Reformat Text

I have a tax calculator for retirees. It produces a report with all the inputs and results. When someone questions an unexpected result, I ask them to send me the report so I can see the full picture. However, Gmail strips all the line breaks and formatting in the report. It comes over as a big block of text, making it hard to decipher what’s going on.

I asked AI to create a skill to reformat the big block of text back to how it looks in the original report. I gave it samples of the report and the text block. AI did a first round. I reviewed the output and asked it to make some adjustments. AI wrote and saved detailed instructions for itself on how to do it. That became a custom skill.

When I receive another big block of text next time, I paste it into chat and say, “Please reformat this.” AI reads the saved instructions and does it. I don’t have to explain the background or my requirements again. AI already has that in the custom skill.

Prescreen Advisors

I maintain a directory of financial advisors who give advice but don’t manage investments. Some advisors start as advice-only but add assets under management after I include them in the directory. Some advisors stop accepting new clients when they reach full capacity. I need to review advisors in the directory periodically.

I asked AI to create a skill for this review. I told AI where to look and what to look for. I asked AI to give me a confidence level for whether an advisor still meets my requirements. AI wrote instructions for itself as another custom skill.

When I need to review an advisor, I identify the firm and ask, “Is this advisor advice-only?” AI loads the saved skill, does the research, and gives me a confidence level and why. I still review manually afterward, but AI’s prescreening has made the review process much easier.

AI may have created software code behind the scenes to perform these tasks. I don’t see the code or run the code. I only make my requests in the chat, as I do in other interactions with AI.

Create a Custom Skill

Creating a skill in AI is like teaching a junior employee. Do it once and hand off the job. It takes some back-and-forth to create it, but it will be easy when you trigger the skill next time.

I’m using Claude in its desktop app. Claude says both free and paid accounts have access to skills. I’m not sure what account levels in other AI services let you create skills.

When you create a skill in AI, start your chat with something like “Please create a skill,” and then describe what you need. Or you can say “Please use your skill-creator skill …” The skill-creator skill is a built-in meta-skill in AI. It knows how to create other skills.

Downloadable Skills

You can also download pre-made skills. I haven’t used any because it’s so easy to create custom skills to do exactly what I want.

If you explore downloadable skills, treat them as any other downloadable software. Only install ones from sources you trust. Skills are human-readable. Read what a skill does before enabling it.

Trigger a Skill

AI knows what skills it has. You usually don’t need a secret handshake to trigger a saved skill. It detects from your chat when it should apply a saved skill. Or you can mention the skill to give it a nudge.

Please use the reformatting skill on this tax calculator report.

You don’t have to use the exact name of the skill. Enough context will give AI clues for which skill to use.

Refine a Skill

Skills are updatable. Like teaching a junior employee, you don’t have to do everything in one go. If your requirements change, or if you see AI getting something wrong when it applies a skill, you can tell AI to update the skill with your new requirements or what mistakes to avoid. The saved skill will become better over time.

Delete a Skill

You can read the skill AI created or delete it when you don’t need it anymore. Different AI services save skills in different places. The Claude desktop app has them under Skills in Settings. Technically, you can also update a saved skill manually, but I would ask AI to update it through chat.

It’s a great value to have a “junior employee” available 24/7, taught to perform tasks to my specifications. I’m sold.