Syntax highlighting, live diagnostics and format-on-save for .diagram files, the diagram language your coding agents
write for EasyDiagram.
Features
Colours headers, groups, nodes, attributes, arrows, labels and comments.
Checks as you type, with the same rules the EasyDiagram server applies, so a file that is clean here is accepted by
your agents and the app. Unknown icons come with a suggestion.
Formats on save (on by default for .diagram files): one statement per line, two-space groups, aligned comments.
Comments are always kept. Run Format Document any time.
type: architecture
direction: right
web "Web app" [icon: monitor]
api "API" [icon: server]
db "Postgres" [icon: postgres, shape: cylinder]
web -> api : HTTPS
api -> db : SQL
Getting started
Save a diagram source as a .diagram file, or ask your agent to.
Edit it: problems appear in the Problems panel and as squiggles, and saving tidies the layout.
Connect your coding agent to EasyDiagram over MCP to have it draw and update diagrams of your code:
see easydiagram.io.
Settings
The extension sets these defaults for .diagram files; override them in your settings under "[diagram]":
Setting
Default
editor.formatOnSave
true
editor.tabSize
2
editor.insertSpaces
true
Open source
The source is on GitHub under the MIT license. Issues and pull
requests are welcome.
