What's a skill, exactly?
A skill is a saved set of instructions, written once by someone who already knows exactly how they want a task done. Think of it like a recipe card: tested until it worked, written down step by step, so anyone can follow it and get the same result, no guessing required.
Ask a plain AI
“Plan me a trip to Rome.”
Handles it fine, the same generic way for everyone who asks.
Use a skill
“Plan my trip exactly the way Trail Boss does it.”
His pacing, his gear checks, his off-the-grid stops, every time.
What a real skill looks like
Hidden Gem Trip Planner
This prompt turns the AI into a local travel guide and logistics expert. Instead of suggesting the usual, overcrowded tourist traps, the AI creates a customized single-day or multi-day plan. It plans smart routes for your preferred transport, finds suitable hotels if needed, checks the current weather and opening hours, watches your budget per person, and finds true hidden gems that exactly match your interests. At the end, you get a clear cost summary.
Features
- Excludes tourist traps and the region's top 5 sights
- Builds a weather- and opening-hours-aware daily route
- Tracks per-person budget with a full cost summary
Example
“Weekend in Lucerne, want to skip the cruise-ship crowds” → Day 1, 10am: Ufschötti lakeside park (68 reviews) instead of the Chapel Bridge crowds — free entry, 15-min walk from the hotel.
How to create a skill
1. Start from a task you already do
Not "plan a trip", but the exact way you'd plan one: your rules, your priorities, your shortcuts.
2. Describe those rules once
Write them the way you'd explain them to a person, then that becomes the skill.
3. Test it, refine it
Run it a few times and adjust the rules until it's consistent, not just lucky once.
4. Publish it
Once it's reliable, others can use that exact same approach, no rebuilding required.
What's inside a skill
The simplest skill is a single file of instructions. Bigger ones are a small folder, with the instructions up front and supporting files the AI pulls in only when it needs them.
Example skill folder
trip-planner/
├── SKILL.md ← instructions (required)
├── references/
│ └── packing-list.md
├── scripts/
│ └── budget.py
└── assets/
└── itinerary-template.docxOnly SKILL.md is required. Everything else is optional.
SKILL.mdRequiredThe heart of every skill. A short header with its name and a one-line description of when to use it, followed by the step-by-step instructions the AI follows.
references/OptionalExtra docs the AI reads only when it needs them: style guides, checklists, examples, policies. Keeps SKILL.md short and focused.
scripts/OptionalSmall helper scripts (Python, JavaScript, shell) for steps that need to be exact every time, like converting a file or crunching numbers.
assets/OptionalFiles the skill uses in its output: document templates, logos, images, fonts, sample data.
manifest.jsonSome assistantsA small config file some assistants use instead of SKILL.md to register a skill, like a ChatGPT plugin manifest or a Gemini extension.json.
Supported file types
When you publish on SkillHub, upload one of these. If your skill has scripts, references, or assets, zip the whole folder.
.mdMarkdownA single SKILL.md, for simple skills that are just instructions.
.zipZip archiveA whole skill folder: SKILL.md plus any references, scripts, and assets.
.jsonJSONA plugin or extension manifest (manifest.json, extension.json) or an OpenAPI spec.
.yaml / .ymlYAMLAn OpenAPI spec, used by ChatGPT actions.
Sketch your own skill
A quick guided example, not a real builder. Skills maker accounts publish the real thing from the Publish page.
Ready to try one yourself?
Browse the full catalogue, or create an account to install skills and publish your own.