Mermaid Validation

Field	Value
Type	Skill Resource
Source	~/.copilot/skills/technical-writing/references/mermaid/validation.md
Description	Not specified

Source Content

Mermaid Validation

Lint Workflow

For a Markdown or MDX file:

python3 ~/.copilot/skills/technical-writing/scripts/mermaid_lint.py /path/to/file.md

For an isolated diagram, write a temp file first:

cat > /tmp/diagram.mmd << 'EOF'
flowchart TD
    A["Start"] --> B{"Done?"}
EOF
python3 ~/.copilot/skills/technical-writing/scripts/mermaid_lint.py /tmp/diagram.mmd

Exit 0 is clean. Exit 1 means errors were found. Fix every error and re-run. If mmdc is installed, the script also runs Mermaid CLI validation.

Common Errors

Wrong	Correct	Why
graph TD	flowchart TD	graph is legacy
A->B	A --> B	Single dash is not a flowchart arrow
A[label: text]	A["label: text"]	Punctuation needs quoting
stateDiagram	stateDiagram-v2	v1 is deprecated
A->>B in flowchart	A --> B	Wrong arrow family
Node ID end	EndState	end is reserved
Bare < in label	&lt; or quoted text	Breaks renderers
classDef in beautiful-mermaid flowchart	style Node ...	Avoid stray visible class node

Final Self-Rubric

• Pre-generation checklist completed.
• Diagram starts with the person/actor when a person drives the flow.
• Roles are visible early enough to answer “where am I?” quickly.
• Role labels use canonical names.
• Diagram answers one reader question.
• Layout is balanced and print-safe.
• Labels are short and concrete.
• No reserved words are used as node IDs.
• Every block opener has a matching end.
• Special-character labels are quoted.
• beautiful-mermaid flowcharts use style, not classDef / class.
• Linter exits 0.