plantuml-ascii Skill for Claude: Draw Diagrams as Plain Text
Makes Claude draw sequence, class and other diagrams as plain text with PlantUML, so they fit in a README, terminal or commit.
- Installs
- 9.8K
- on skills.sh
- Stars
- 40.7K
- on GitHub
- Updated
- Oct 2026
- last repo commit
Claude writes a PlantUML file, then runs plantuml -txt for pure ASCII or plantuml -utxt for box-drawing characters. The result is saved next to the source as diagram.atxt or diagram.utxt. SKILL.md covers seven diagram types and lists the command-line options.
It needs PlantUML on your machine. SKILL.md lists brew, apt, yum and a direct JAR download for it, and allows the Bash, Write and Read tools. It also tells Claude to keep diagrams simple, because complex ones do not render well in ASCII.
Good for
- Developers who document in READMEs, commits or PRs that cannot show images
- Terminal users who want diagrams without a graphics tool
- Teams that keep diagrams in version control as text
Install plantuml-ascii
Claude Code
- 1
Download the skill folder from https://github.com/github/awesome-copilot/tree/HEAD/skills/plantuml-ascii.
- 2
Put it at ~/.claude/skills/plantuml-ascii/ so that SKILL.md sits directly inside.
- 3
Start a new session; the skill loads when its description matches the task.
Install PlantUML first: SKILL.md lists brew install plantuml (macOS), sudo apt-get install plantuml or sudo yum install plantuml (Linux), or the PlantUML JAR run with java -jar (needs Java). It runs on your own machine, so there is no Claude app upload tab.
Built from the package data we hold. Not yet tested by us.
What's in the skill
When it loads
Generate ASCII art diagrams using PlantUML text mode. Use when user asks to create ASCII diagrams, text-based diagrams, terminal-friendly diagrams, or mentions plantuml ascii, text diagram, ascii art diagram. Supports: Converting PlantUML diagrams to ASCII art, Creating sequence diagrams, class diagrams, flowcharts in ASCII format, Generating Unicode-enhanced ASCII art with -utxt flag
Sections in SKILL.md
- Overview
- What is PlantUML ASCII Art?
- Installation
- Output Formats
- Basic Workflow
- 1. Create PlantUML Diagram File
- 2. Generate ASCII Art
- 3. View Output
- Diagram Types Supported
- Sequence Diagram
- Class Diagram
- Activity Diagram
- State Diagram
- Component Diagram
- Use Case Diagram
- Deployment Diagram
Key facts
- Installs on skills.sh
- 9,756 (Nov 2, 2026)
- GitHub stars
- 40,666 for the whole repo (Nov 2, 2026)
- Last repo commit
- Oct 30, 2026
- What it includes
- 1 file: SKILL.md (no scripts)
What it includes
Writes a .puml diagram file
Write ·
Create the PlantUML fileRuns plantuml -txt to make pure ASCII output
Saves the result as diagram.atxt next to the source file.
Runs code ·
Generate ASCII (-txt)Runs plantuml -utxt for box-drawing characters
Saves the result as diagram.utxt. SKILL.md calls it better looking.
Runs code ·
Generate Unicode art (-utxt)Sequence, class, activity, state, component, use case, deployment
SKILL.md has an example for each of these seven types.
Diagram typesOutput directory, whole-folder runs, -includeDot, -v, -charset
Lists plantuml options such as -o for an output folder, processing a whole directory and setting the charset.
Runs code ·
Command-line optionsShows an Ant target that generates txt or utxt output
Ant taskKeep diagrams simple, use short labels, use a fixed-width font
Five tips and four troubleshooting entries, such as garbled Unicode or a missing plantuml command.
Tips and troubleshooting
From the official docs
Permissions
Low risk
Claude runs PlantUML in your shell and writes diagram text files. Install PlantUML yourself and check the output folder before running it on many files.
What it can do
- Read your data
- Create and change things
- Delete things
- Read-only mode
Watch out for
It shows commands that install software
The installation section lists brew, apt-get and yum installs, and a wget download of a PlantUML JAR from github.com. Install PlantUML yourself and review any install command Claude proposes. github.com
It writes files next to your sources
Output goes to files such as diagram.atxt, or to the folder you pass with -o. Check the target path before you run it over a folder of diagrams. github.com
Technical details
| Turning on read-only | SKILL.md has no read-only mode. |
|---|---|
| Talks to | github.com (the SKILL.md install section shows downloading a PlantUML JAR with wget) |
| Scopes |
|
Questions
What does the plantuml-ascii skill do?
It makes Claude generate diagrams as plain-text art using PlantUML text mode. It supports sequence, class, activity, state, component, use case and deployment diagrams.
Do I need PlantUML installed?
Yes. SKILL.md lists brew install plantuml on macOS, apt or yum on Linux, or a direct JAR download that you run with Java. Install it yourself before asking Claude to generate diagrams.
What is the difference between -txt and -utxt?
-txt makes pure ASCII, and -utxt uses box-drawing Unicode characters for a cleaner look. SKILL.md recommends -utxt and testing in a fixed-width font. For garbled Unicode it says to make sure the terminal supports UTF-8 and has a proper font.
How do I install the skill?
Use the install box at the top of this page. It has no Claude app upload tab, because the skill runs PlantUML on your own machine.
Is it better than Mermaid?
This skill outputs plain-text art that shows anywhere, such as terminals and commits. SKILL.md itself says that for complex diagrams you should consider Mermaid.js or graphviz.
Is it safe to install?
The skill folder holds one file and bundles no scripts. When you use it, Claude runs plantuml and writes diagram files in your folder. SKILL.md also shows install commands (brew, apt, yum, and downloading a JAR with wget), so read any command before it runs.
Information
updated Nov 2, 2026
- Repository
- github/awesome-copilot
- Folder
skills/plantuml-ascii
Sources
Docs, issue trackers and discussions this page is built from.
Show all 1Hide
- skills/plantuml-ascii/SKILL.md · github.com