Guide · Agent skill
How to use the Em Dash Avoidance Guide agent skill
Updated · written with AI from the project's own documentation and checked against our catalogue data
The em-dash skill is a text rule for an AI agent. When the agent writes or reviews code, comments, or data files, it avoids em dashes (—) and en dashes (–) and replaces any it finds with a plain hyphen (-). This guide explains what the skill does, how to install it, how to trigger it, and where it may not fit your work, so you can decide whether it helps your project.
Em Dash Avoidance Guidegithub/awesome-copilot · MIT Download the skill Quick start
- 1Download the ZIP. Get the em-dash skill ZIP from this page.
- 2Choose an install location. Pick ~/.claude/skills/ for personal use or the project's .claude/skills/ folder for one project.
- 3Unzip the skill. Extract the ZIP so the em-dash folder with SKILL.md sits in the chosen skills folder.
- 4Or upload it in the Claude apps. In the Claude apps, go to Settings → Capabilities → Skills and upload the skill.
- 5Ask for code or comments. Make a normal request that involves writing or reviewing code, comments, or data files.
- 6Check the output. Review the agent's dash changes, especially in data files, before you commit.
What is an agent skill and what does the em-dash skill do?
An agent skill is a folder containing a SKILL.md file with instructions that an AI agent can load when a task matches the skill's description. The em-dash skill is one such folder. Its description says it is an expert on the history, origin, and correct use of the em dash, and it applies when writing or reviewing code, comments, or data files.
By default the skill tells the agent to never use em or en dashes in code. If the agent finds one in a comment, it replaces it with the hyphen-minus character (-). The skill also includes a history of the em dash and a reference on how commas, colons, semicolons, and other punctuation marks are used.
- Code comments: avoid em and en dashes, and replace any found with -.
- Raw data and text files: default to never, and leave dashes that are already present in the data.
- Reference material: a history of the em dash and guidance on other punctuation marks.
Install the em-dash skill from the ZIP download
Download the ZIP for the em-dash skill from this page. Then install it in one of two ways. For a personal setup, unzip it into ~/.claude/skills/. For a single project, unzip it into that project's .claude/skills/ folder.
If you use the Claude apps, you can instead upload the skill under Settings → Capabilities → Skills.
- Personal install: unzip into ~/.claude/skills/
- Project install: unzip into the project's .claude/skills/ folder
- Claude apps: Settings → Capabilities → Skills, then upload
How to trigger the skill with natural requests
You do not need a special command. The skill is meant to be picked up when your request matches its description, which covers writing or reviewing code, comments, or data files where you want to avoid em and en dashes. Ask for the task in plain language and mention the dash rule if you want to be sure it applies.
The source does not list a fixed set of trigger phrases, so treat the examples below as ways to phrase a normal request rather than guaranteed keywords.
- Write a Python function for parsing dates and add comments that avoid em dashes.
- Review this config file and replace any em or en dashes with hyphens.
- Add code comments to this module using only plain hyphens.
Examples of what the agent does with the skill
Suppose a code comment reads: // load settings — fall back to defaults if missing. With the skill active, the agent should replace the em dash with a hyphen, giving // load settings - fall back to defaults if missing.
For data files, the default is different. If an em dash is already part of the data, the skill says to leave it alone. Replacing dashes in data therefore needs an explicit instruction, and the agent may still keep existing ones.
// load settings - fall back to defaults if missingWhat the skill needs, and safety notes
The skill lists no requirements. It does not run scripts and does not use the network. Its SKILL.md file contains only text instructions, so it changes how the agent writes, not what runs on your computer.
Because it is a style rule, review the agent's output as you would any edit. It can change dashes in files you did not intend to touch, so check diffs before committing.
- Requires: nothing listed
- Runs scripts: no
- Uses network: no
- Files: SKILL.md
Tips and when not to use it
Use the skill when you want plain ASCII hyphens in comments, or when a linter or parser fails on typographic dashes in source or config files. It is a good fit for teams that want consistent text in code.
Do not use it for prose or published writing where em dashes are a deliberate style choice, since the rule defaults to never using them and may distort the text. It may also conflict with a replace-everything goal in data files, because the skill says to leave existing dashes alone.
- Good fit: code comments that must be plain ASCII, or config files that break on typographic dashes.
- Poor fit: published prose where em dashes are a deliberate style choice.
- Check conflicts: data files where existing em dashes must be kept.
What people use it for
- Keeping code comments in plain ASCII so editors and terminals display them consistently.
- Cleaning typographic dashes out of config or source files that a linter or parser rejects.
- Reviewing a code change to find and replace em or en dashes in comments.
- Studying the history of the em dash and the rules for other punctuation marks.
Frequently asked questions
Is the em-dash agent skill free?
The skill is published under the MIT licence in the github/awesome-copilot repository, as stated on this page. The source does not list a price, so check the repository for the licence terms that apply to you.
What are the requirements for the em-dash skill?
The skill lists no requirements. It does not run scripts and does not use the network, and its only file is SKILL.md.
Where do I install the em-dash skill?
Unzip the ZIP into ~/.claude/skills/ for personal use, or into a project's .claude/skills/ folder. In the Claude apps you can upload it under Settings → Capabilities → Skills.
Why does the agent replace em dashes with hyphens?
The skill sets a default of never using em or en dashes in code. When it finds one in a comment, it replaces it with the hyphen-minus character (-), which is a plain ASCII character.
Will the skill change dashes in my data files?
Not by default. For raw data and text files the skill says to leave dashes that are already part of the data. Replacing them may need an explicit instruction, and this can conflict with a replace-everything goal.
Should I use this skill for my writing or only for code?
The skill is aimed at code, comments, and data files. Its default rule would distort prose where em dashes are a deliberate style choice, so it is a poor fit for published writing.
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Our verdict
Use the em-dash skill if you want code comments and config files to use only plain hyphens, or if a linter or parser fails on typographic dashes. Pick something else if you write prose where em dashes are a deliberate style choice, or if you need to keep existing dashes in data files.
Download the skill