# Gemini Skills: Reusable Prompts for Gemini Notebook (formerly NotebookLM)
> What Gemini skills are, how to create them, skills vs Gems, how Claude and ChatGPT skills compare, and how to keep a reusable prompt library for NotebookLM.
By Juli · Published Oct 26, 2026 · https://www.kortex-notebooklm.com/blog/gemini-skills-prompt-library
You open a chat and type the same paragraph you typed yesterday: quote the source for every claim, keep it short, end with three questions so I can check I understood. Gemini skills exist so you can stop doing that. A Gemini skill saves those instructions once, and you call them with a slash. Claude and ChatGPT have skills too, built on the same kind of file. Gemini Notebook (formerly NotebookLM), the app where a lot of that reading happens, has none. This guide explains how Gemini skills work, how they differ from Gems and from Claude and ChatGPT skills, and how to keep one prompt library that also works inside Gemini Notebook.
We analyzed Google's autocomplete suggestions for "gemini skills" in October 2026, and they read like a list of open questions. People finish the phrase with "vs gems", "like claude", "in chrome", "list" and "examples", plus three different ways of asking how to make one. This guide answers each of them: what the feature is, where the menus are, and what to put in your first skills.
> **Key Takeaways**
> - A Gemini skill is a saved set of instructions you call with / or @, and Gemini can apply it on its own when it fits ([Gemini Apps Help](https://support.google.com/gemini/answer/17094296?hl=en)).
> - Skills are free on personal Google Accounts (18+) and are replacing Gems.
> - Claude and ChatGPT skills use the same SKILL.md shape, so one file can serve all three.
> - Gemini Notebook has no skills. Its Configure Chat holds one role per notebook; a saved prompt library covers the rest.
## What are Gemini skills?
A **Gemini skill** is a saved set of instructions, plus any reference files, that teaches Gemini how to do one task your way. Google's help center calls it "a set of reusable instructions and additional context" that shows Gemini how to handle a specific task and which tools to use ([Gemini Apps Help](https://support.google.com/gemini/answer/17094296?hl=en)). To call one, type / in any chat (or @, if you have the updated shortcut) and pick it from the list. However, you don't always have to. Gemini can use an activated skill on its own when your request matches it, and it can combine several skills in one task.
Skills live on one page. In the Gemini sidebar, click **Customize** (under **More** if you don't see it), then **Skills** at the top. That page is your Gemini skills list, with a **Recommended** row of templates to start from. You can keep up to 100 skills active at a time ([Gemini Apps Help](https://support.google.com/gemini/answer/18560919?hl=en)).
Who gets them? Skills work in the Gemini web app at gemini.google.com, the mobile app and the Mac app, and Google says they don't need a Google AI subscription. You do need to be 18 or older, signed in to a personal Google Account, with Keep Activity turned on. Work and school accounts don't have skills.
One limit catches people moving from Gems. Skills work with connected apps such as the Workspace apps, but most of the default tools Gems could use don't run inside a skill, including Canvas, Deep Research, Guided Learning, and video and music creation (Gemini Apps Help). So a skill is best at the thing it was built for: telling Gemini how you want a job done, the same way every time.
## How do you create Gemini skills?
There are four ways to make one, from least effort to most. Google documents all four on the same help page.
1. **Ask in a chat.** Type something like "Create a skill that turns any paper I share into a one-page brief." Gemini drafts the skill and saves it to your Skills page. To change it, describe the change in the same chat.
2. **Use Create with Gemini.** On the Skills page, choose **Create with Gemini**. A chat opens, and Gemini works through the task with you.
3. **Start from a template.** Pick one under **Recommended** and edit it, or start blank and fill in three fields: name, description and instructions.
4. **Upload a file.** Upload a `SKILL.md` file, or a folder or `.zip` whose main folder holds `SKILL.md`. This is how you bring in a skill written for Claude.
### What are the rules for uploaded skills?
Uploads follow a handful of rules ([Gemini Apps Help](https://support.google.com/gemini/answer/17094296?hl=en)):
- The skill name must be lowercase with hyphens between words, such as `paper-brief`.
- Reference files only come in with the upload. Plain text, PDFs, images and some code and data files work; `.docx` and `.xlsx` don't.
- Everything together must stay under 100 MB.
- Scripts can't use the internet or act on other websites.
- Uploading works on the web app and the Mac app only, not on phones.
### Write the description before the instructions
The description decides when a skill fires on its own. Google's first best practice is to "describe specific situations when Gemini should use the skill automatically" (Gemini Apps Help). Anthropic says the same about Claude: a skill's description is "the only part Claude reads before deciding to load the skill" ([Claude docs](https://claude.com/docs/skills/how-to)). So write the description as a trigger: what the skill does, then the words you'd type when you want it. For example, "Use when I say quiz me, test me or help me revise" beats "A study helper".
You manage skills from the same page. **Deactivate** stops Gemini using a skill on its own (ask for it by name and Gemini offers to switch it back on). **Edit** changes the description and instructions, **Download** saves a `.zip`, and **Delete** removes it for good. To change a skill's files, you upload the whole skill again.
## Gemini skills vs Gems: what's the difference?
Skills replace Gems. A Gem was a separate version of Gemini that you opened on its own page. A skill, by contrast, is a set of instructions you pull into any chat, and Gemini can pull it in for you. Google lists the differences on its transition page ([Gemini Apps Help](https://support.google.com/gemini/answer/18560919?hl=en)):
| | Gems | Skills |
|---|---|---|
| How you start one | Open the Gem's own page | Type / or @ in any chat |
| Can Gemini pick it for you? | No | Yes, when it's activated and relevant |
| More than one at once? | One Gem per chat | Several skills in one chat |
| Reference files | Gem knowledge files | Uploaded with the skill, up to 100 MB |
| Canvas, Deep Research, Guided Learning | Available | Not available inside a skill |
| Sharing with others | Available | Not available |
The switch has dates attached. On personal accounts, Gems turn read-only on **November 17, 2026** and disappear on **December 17, 2026**. Google recreates each Gem as a skill automatically, but some knowledge files won't make the trip: audio, video, archives such as `.zip` and old Office formats such as `.doc`. If a Gem holds more than 100 MB, its largest files are dropped first. Download those from the Gem before December 17, 2026. Work and school accounts are on a later schedule, which the transition page lists. If you're still sorting out where Gems sat next to notebooks, our [Notebooks in Gemini vs Gemini Notebook guide](/blog/gemini-notebook-vs-notebooks-in-gemini) maps all of them.
## What are Gemini skills in Chrome?
They're a separate feature that shares the name. Gemini in Chrome skills are saved prompts that run on the page you're looking at: Gemini reads your active tab and applies your instructions to it ([Gemini Apps Help](https://support.google.com/gemini/answer/16988996?hl=en)). Google's examples include "Check job fit" and "Explain simply".
To make one, click **Ask Gemini** in Chrome, type /, choose **Add Skill +**, enter a name and a prompt, and save. Chrome also has a built-in skills library you can browse and remix at `chrome://skills/browse`, and your own list at `chrome://skills/yourSkills`. It needs a Mac, Windows computer or Chromebook Plus, Chrome's language set to English (United States), and a personal Google Account; managed accounts only get it if an admin turns it on.
Google's help pages treat Chrome skills and Gemini app skills separately and don't say they sync. So plan for two lists, which is one more reason to keep a master copy of your prompts somewhere you control.
## Claude skills vs ChatGPT skills: how do they compare?
Same idea, same kind of file, different doors. All three assistants store a skill as a name, a description and instructions, and all three can load a skill without being asked when your request matches it. What differs is who gets them and how you call one.
### Claude skills
Claude's skills are "folders of instructions, scripts, and resources that Claude loads dynamically" for specialised tasks ([Claude Help Center](https://support.claude.com/en/articles/12512176-what-are-skills)). Find them under **Customize > Skills** in claude.ai or the desktop app, turn one on, then either describe your task or type / in the message box and pick the skill ([Claude docs](https://claude.com/docs/skills/overview)). Skills run in Claude's code sandbox, so **Code execution and file creation** has to be on under **Settings > Capabilities**. Anthropic's skills docs list Pro, Max, Team and Enterprise; its help center also describes Free accounts turning skills on, so check your own Customize page.
To make one, ask Claude to use its built-in **skill-creator** skill and edit what it drafts, or write the `SKILL.md` yourself. To upload, zip the skill's folder (not the files inside it) and add it under Customize > Skills. In Claude Code, a skill folder in `~/.claude/skills/` works as `/skill-name`.
### Claude skills vs Projects
A **Claude Project** is a workspace whose background knowledge is loaded in every chat inside it. A skill is a procedure that loads only when a task needs it, in any chat. Anthropic draws the same line: Projects "provide static background knowledge", while skills "activate dynamically when needed and work everywhere across Claude" (Claude Help Center). In practice, the course reader goes in the Project, and "turn this reading into flashcards" goes in a skill. For how Projects stack up against notebooks, see [Gemini Notebook vs Claude Projects](/blog/gemini-notebook-vs-claude-projects).
### ChatGPT skills
ChatGPT calls them skills too. OpenAI describes them as "reusable, shareable workflows" that ChatGPT can use automatically when they help ([OpenAI Help Center](https://help.openai.com/en/articles/20001066-skills-in-chatgpt)). They sit under **Plugins** in the sidebar, on the **Skills** tab, and you can create one with chat, build it in the editor or upload one. Eligible accounts start with a skill-creator skill already installed. The catch is the plan: OpenAI lists skills for eligible ChatGPT Business, Enterprise, Healthcare and Edu users.
On a personal plan without a Skills tab, use project instructions. In a ChatGPT Project, **Project settings** holds instructions that apply to every chat in that project ([OpenAI Help Center](https://help.openai.com/en/articles/10169521-projects-in-chatgpt)). Custom GPTs aren't the answer either: personal accounts (Free, Go, Plus and Pro) can't create new GPTs, and OpenAI is moving them over to plugins ([OpenAI Help Center](https://help.openai.com/en/articles/8554397-creating-a-gpt)).
| | Gemini skills | Claude skills | ChatGPT skills |
|---|---|---|---|
| Where they live | Customize > Skills | Customize > Skills | Plugins > Skills tab |
| Who gets them | Personal Google Accounts, 18+, no subscription | Paid plans per Anthropic's docs; code execution on | Eligible Business, Enterprise, Healthcare, Edu |
| How you call one | Type / or @ and pick | Type / and pick | ChatGPT uses installed skills on its own |
| Ways to create | Chat, Create with Gemini, template, upload | skill-creator, write SKILL.md, upload ZIP | Chat, editor, upload |
| Share with others | No | Team and Enterprise | Within the workspace |
### Are Gemini skills like Claude skills?
Close enough that one file can serve both. Google says so directly: "you can import skills you created on other platforms by uploading their SKILL.md files" (Gemini Apps Help). Claude's skills follow an open standard, the [Agent Skills specification](https://agentskills.io/specification): a `SKILL.md` file whose `name` uses lowercase letters, numbers and hyphens and whose `description` says when to use it. Gemini's upload asks for the same shape. Packaging differs a little: Claude wants the folder zipped, while Gemini also takes a bare `SKILL.md`. Scripts are where portability ends, since Gemini blocks scripts that need the internet.
## Does Gemini Notebook have skills?
No. Gemini Notebook's help pages describe no skills and no saved prompts. Its closest tool is Configure Chat. **Configure Chat** is the Chat panel setting where you pick a conversational style and a response length. The styles are Default, Learning Guide ("best for educational content") and Custom, which takes a role or style in your own words, such as Google's example "Respond like a PhD student" ([Gemini Notebook Help](https://support.google.com/gemininotebook/answer/16179559?hl=en)). When Google introduced custom goals, it described them as letting "each notebook" adapt to you ([Google](https://blog.google/innovation-and-ai/models-and-research/google-labs/notebooklm-custom-personas-engine-upgrade/)).
That gives you one standing instruction per notebook. It can't hold your paper brief, your quiz routine and your claim checker at once, and it doesn't follow you to the next notebook. Studio outputs, likewise, take their instructions one generation at a time. Gemini app skills don't change that, because they run in the Gemini app, not inside Gemini Notebook. So you retype.
The fix is to split every skill in two. The **role** ("act as my thesis supervisor; be blunt about weak evidence") is the part that should colour every answer, so it goes in Configure Chat > Custom for that notebook. The **tasks** ("brief this paper", "quiz me", "check this draft") are the parts you fire on demand, so they go in a saved prompt library you can open from any notebook. As a bonus, Gemini Notebook answers only from your sources, which suits source-checking instructions better than a general chat does. Our [30 best Gemini Notebook prompts](/blog/best-notebooklm-prompts) are written for that grounding.
## Which skills are worth building for research and study?
Anything you type twice. Google pitches skills as the alternative to "retyping prompts for recurring tasks" (Gemini Apps Help), and Anthropic's guidance on choosing one fits every assistant. A skill "pays off when Claude does a task for you repeatedly and you want it done the same way every time", especially where you keep correcting it "with the same instructions". For a one-off task, it adds, just describe it in the conversation (Claude docs). Here are four Gemini skills examples for research and study, written out in full. Paste one into Gemini's blank template, save it as `SKILL.md` for upload, or copy the part under the second `---` into a saved prompt for Gemini Notebook.
### 1. cite-or-flag: check a draft against your sources
```markdown
---
name: cite-or-flag
description: Checks a summary, answer or draft against the sources in this chat. Use when I ask to fact-check, verify or "check this against my sources".
---
1. Split the text into single claims, one per line. Keep my wording.
2. For each claim, quote the sentence in my sources that supports it and name the source.
3. If no sentence supports it, write NOT IN SOURCES. Never fill the gap from memory.
4. If a source says something different, write CONFLICT and quote both.
5. End with a count: supported, not in sources, conflicting.
```
**Why it earns a skill:** checking is the step people skip when they're tired. In Gemini Notebook, where answers come only from your sources, the NOT IN SOURCES lines are the useful part. It also catches the gaps a fluent summary hides.
### 2. paper-brief: one page per research paper
```markdown
---
name: paper-brief
description: Turns one research paper into a one-page brief. Use when I share a paper, PDF or abstract and ask what it says, whether it holds up, or how it fits my project.
---
Write these sections, in this order, using only the paper:
- Question: what the authors set out to answer, in one sentence.
- Method and sample: the design, who or what was studied, and how many.
- Findings: the three results that matter most, with numbers as reported.
- Limits: what the authors admit, then what they don't (small sample, no control group, self-reported data).
- For my project: how this supports or changes [MY RESEARCH QUESTION]. If you don't know my question, ask before writing this part.
Give the page or section for every number.
```
**Why it earns a skill:** the same five questions apply to every paper, and the last one makes the brief about your work. In a saved prompt, fill [MY RESEARCH QUESTION] once per project.
### 3. exam-drill: quiz me one question at a time
```markdown
---
name: exam-drill
description: Quizzes me on study material, one question at a time. Use when I say quiz me, test me, drill me or help me revise.
---
1. Ask which topic and how many questions. Default to 10.
2. Ask one question at a time. Mix recall ("define..."), application ("what happens if...") and comparison ("how does X differ from Y"). Don't show the answer.
3. Wait for my answer. Mark it right, partly right or wrong, and explain in two sentences from the material.
4. Keep a list of what I missed and ask those again, reworded, at the end.
5. Finish with my score and the three ideas to review first.
No multiple choice unless I ask for it.
```
**Why it earns a skill:** answering questions beats rereading. **Retrieval practice** is the habit of pulling answers from memory instead of reviewing notes, and in Roediger and Karpicke's experiments, students who took recall tests remembered more a week later than students who restudied ([Roediger & Karpicke](https://pubmed.ncbi.nlm.nih.gov/16507066/), 2006). The "wait for my answer" line is what stops a chatbot from dumping the whole quiz at once. In Gemini Notebook, pair it with the Learning Guide style.
### 4. lit-matrix: compare several sources in one table
```markdown
---
name: lit-matrix
description: Builds a comparison table across several papers or sources. Use when I ask to compare studies, map the literature, or find where sources agree and disagree.
---
Make a table with one row per source and these columns: author and year, question, method, sample, main finding, limitation.
Below the table, write three short lists:
- Agreement: findings two or more sources share, with the sources named.
- Disagreement: where sources conflict, and the likely reason (different samples, methods or definitions).
- Gaps: questions none of the sources answer.
Use only the sources given. Write "not reported" when a column doesn't apply.
```
**Why it earns a skill:** a literature review starts with this table every time, and the Gaps list is where the next research question usually hides. It shines in a Gemini Notebook notebook with ten or more papers.
Saved once, each of these is a shortcut instead of a paragraph.
Keep these four skills one shortcut away in Gemini Notebook
Save each instruction block in Kortex once, then type ;drill or ;brief in the chat box of Gemini Notebook, ChatGPT, Claude or Gemini. The free plan keeps 10 saved prompts. Free on Chrome.
## How do you keep one prompt library for Gemini, Claude, ChatGPT and Gemini Notebook?
Write each prompt once, in the skill shape, and copy it outward. A prompt library for AI chats works when there's one master copy and every tool gets the same text. It takes five steps.
1. **Write every prompt as a skill.** Give it a name, a one-line "use when" description and the instructions. That shape uploads to Gemini and Claude, and it doubles as a clear label in any prompt manager.
2. **Keep the master copy in one place.** A folder of `SKILL.md` files works; so does a prompt manager. Edit the master, then re-upload, since Gemini makes you upload the whole skill again to change its files.
3. **Upload where skills exist.** Gemini (web or Mac app), Claude (zip the folder) and ChatGPT, if your workspace has skills.
4. **Save the instructions as prompts where skills don't.** That means Gemini Notebook, ChatGPT personal plans (or a Project's instructions) and other chat tools.
5. **Mark the blanks.** Put a placeholder like [TOPIC] or [MY RESEARCH QUESTION] wherever the prompt needs filling in.
One master copy, three destinations. Menu names from Gemini Apps Help, Gemini Notebook Help and Anthropic's Claude docs; the ;shortcut is a Kortex feature.
Step 4 is the one Kortex handles. **Kortex** is a free Chrome extension for Gemini Notebook, and we built it, so weigh this section accordingly. It adds a **Prompts** button beside Share in Gemini Notebook that inserts a saved prompt into the chat ([Kortex docs](/docs/prompt-holder-button)). The dashboard's Prompts Library sorts prompts into folders, with tags, search and favourites. Each prompt can have a shortcut: type ;drill in the chat box in Gemini Notebook, ChatGPT, Claude, Gemini, Perplexity and the other sites Kortex supports, and the prompt drops in. On any other page, ⌘⇧P (Ctrl+Shift+P on Windows) opens your prompts. The free plan keeps 10 saved prompts and 5 folders; Pro, at $9.99 a month or $4.92 a month billed yearly, removes the cap.
There's one more path for Pro and Lifetime members. Kortex MCP, included with both, gives Claude and ChatGPT tools to list your saved prompts and fill a prompt's placeholders, so the same library answers from inside a chat ([Kortex MCP tools](/docs/mcp-tools)). Our guide to [connecting Gemini Notebook to Claude and ChatGPT](/blog/gemini-notebook-in-claude) covers the setup.
Want a head start without writing anything? The site's [copy-ready Gemini Notebook prompts](/prompts) cover study guides, quizzes, literature reviews and meeting notes, and the free [prompt library tool](/tools/prompt-library) lets you search and filter 50 prompts by category.
## What should you turn into a skill first?
Start with the prompt you've typed most often. In short: Gemini skills are saved instructions you call with / or @, they're free on personal accounts and they replace Gems. Claude and ChatGPT skills use the same file, though ChatGPT keeps them to workspace plans. Gemini Notebook has no skills at all, so give each notebook a role in Configure Chat and keep the tasks in a prompt library you can reach from every chat box.
One prompt library for every chat box
Kortex keeps your saved prompts in Gemini Notebook and the AI chats it supports, with folders, tags and a ;shortcut for each one. 10 saved prompts free, unlimited on Pro. Free on Chrome.
## Frequently asked questions
### What is a Gemini skill, in one sentence?
A Gemini skill is a saved set of instructions, plus any reference files, that teaches Gemini how to do one task your way. You call it by typing / (or @, on the updated shortcut) in a chat, and Gemini can also apply an activated skill on its own when your request matches it.
### Are Gemini skills free?
Yes. Google says skills don't need a Google AI subscription. You need to be 18 or older, signed in to a personal Google Account, with Keep Activity on. Skills work in chats on the web, the mobile app and the Mac app; tasks and schedules are the parts that need a subscription.
### What happens to my Gems?
Google recreates them as skills automatically. On personal accounts, Gems turn read-only on November 17, 2026 and are removed on December 17, 2026. Files that can't carry over, such as audio, video, archives, old Office formats or anything beyond 100 MB, should be downloaded from the Gem before December 17, 2026.
### Can I use a Claude skill in Gemini?
Usually, yes. Gemini's upload takes a SKILL.md file, a folder or a .zip with SKILL.md in its main folder, which is the same file a Claude skill is built on. The name must be lowercase with hyphens, scripts can't use the internet, and uploading works on the web and the Mac app only.
### Does Gemini Notebook support skills?
No. Gemini Notebook (formerly NotebookLM) has Configure Chat, which sets one conversational style or role per notebook, but no skills and no saved prompts. A prompt library such as Kortex's fills that gap: it adds a Prompts button and a ;shortcut to the Gemini Notebook chat box.
### Are ChatGPT skills available on Plus?
OpenAI's help center lists skills for eligible ChatGPT Business, Enterprise, Healthcare and Edu users, found under Plugins and then the Skills tab. If your plan doesn't show a Skills tab, project instructions are the dependable equivalent: they apply to every chat inside that project.
---
*Editorial note: fact-checked against the official help pages and docs linked above on October 26, 2026. Spotted something out of date? [Contact us](/support) and we will fix it, or read more [about Kortex](/about).*