Guide 4 of 6, 5 min read
How to use AI skills in ChatGPT, Gemini and other chatbots
Turn any SKILL.md skill into reusable instructions for a custom GPT, a ChatGPT project, a Gemini Gem or a single chat.
Skills were designed for Claude, and support for the same SKILL.md format is spreading to other assistants, which change quickly. Where an assistant does not read the file, the idea still works in any chatbot: write down how a job should be done, once, and have the assistant follow it every time. ChatGPT, Gemini and most other assistants have a place to keep standing instructions. A skill's instructions fit straight into it.
Step 1: copy the instructions
Every skill page on Promptlexity has a Copy as instructions button. It copies the skill's full instructions, plus any reference files it includes, as one block of plain text. You do not need to unzip anything.
Pick a skill from the skills library. The brand voice skill and the Socratic tutor are good ones to start with, because the difference is easy to see.
Step 2: choose where to paste them
Where you paste depends on how often you need the skill.
For a job you do all the time: a custom GPT or a Gem
- ChatGPT. Create a custom GPT and paste the instructions into its Instructions field. Give it a name that matches the skill. Every chat with that GPT now follows the skill.
- Gemini. Google is moving the Gemini app from Gems to skills. If your app offers skills, upload the SKILL.md directly. If it still offers Gems, create one and paste the instructions into the instructions box.
This is the closest match to how skills work in Claude: set up once, use as often as you like.
For a project with its own files: project instructions
ChatGPT and Claude both let you group chats into projects with shared instructions and files. Paste the skill into the project instructions if it only applies to that piece of work, for example the brand voice skill for one client.
For a one-off: the start of a chat
Paste the instructions as your first message, then add "Follow these instructions for the rest of this chat. Reply OK if you understand." Then send your actual request. This works in any chatbot, including ones with no settings at all.
Step 3: test it
Ask for the job the skill is for and compare the answer with what you usually get. With the weekly review skill, paste last week's notes and ask for a review. The answer should follow the steps the skill lays out.
What is different from Claude
A few things work differently outside Claude:
- No automatic switching. Claude decides on its own when to use a skill. In ChatGPT or Gemini, the instructions apply to every message in that GPT, Gem or chat, so keep one skill per GPT or Gem.
- Reference files are pasted in. In Claude, extra files load only when needed. When you copy as instructions, they are included in full, which uses more of the context window. For most skills on this site that is a few hundred words, so it does not matter.
- Scripts do not run. Some skills elsewhere include code that Claude can run. The skills on Promptlexity are instructions only, so they work the same everywhere.
Make it yours
The instructions are plain English. Before you paste, add a line or two about your situation: your audience, your style rules, what to leave out. The custom instructions writer prompt can help you turn your preferences into clear standing instructions.