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name: diagram-quality description: "PlantUML diagram quality on the agent-uml collaborative canvas — three tiers: rendering safety (syntax that prevents HTTP 400 blank canvas), conversation mechanics (when to push a version vs ask a question, what to write in the message parameter), and design effectiveness (decomposition thresholds, cross-diagram traceability, export readiness). Trigger whenever calling agent-uml MCP tools (design_create, diagram_upsert, design_feedback, design_export) — even when the task seems simple, since a missing as alias makes elements un-annotatable and a skinparam mismatch makes diagrams unreadable."

agent-uml Diagram Quality Best Practices

Make the human-Claude design conversation converge faster on the agent-uml canvas.

When to Apply

• Before every diagram_upsert call — check syntax safety rules and apply the correct skinparam preset
• After every design_feedback response — consult the versioning decision table to choose the right next action
• When starting a new design session — follow the progressive detail layers for diagram ordering
• Before calling design_export — run the export-readiness checklist
• When a diagram renders blank or elements aren't clickable — consult rendering safety rules

Rule Categories by Priority

Priority	Section	Impact	Reference
1	Rendering Safety	CRITICAL	syn-safety.md, _presets.md
2	Conversation Mechanics	HIGH	_conversation.md
3	Design Effectiveness	MEDIUM	_design.md

Quick Reference

1. Rendering Safety (CRITICAL)

18 rules that prevent blank canvas and ensure interactive SVG. Read syn-safety.md before writing any PlantUML source.

Key rules:

• Every element gets as Alias — without it, element is not clickable on canvas
• skinparam backgroundColor transparent — white default clashes with #f4f1ec canvas
• Copy the correct preset from _presets.md — one block per diagram type, matched to canvas CSS variables

2. Conversation Mechanics (HIGH)

5 decision tables for the feedback-response loop. Read _conversation.md when deciding what tool to call next.

Key tables:

• Table 4: Signal → Action — maps annotation, chat, silence, and timeout to the correct tool call
• Table 5: Message content — what to write in the message parameter (explain change + ask focusing question)

3. Design Effectiveness (MEDIUM)

4 heuristics with concrete thresholds. Read _design.md when planning diagram sequences or preparing for export.

Key heuristics:

• Progressive detail layers — L1 context → L2 container → L3 class → L4 behavior → L5 state
• Cross-reference traceability — every sequence participant must map to a component; every interface belongs to exactly one component boundary
• Decomposition thresholds — component >12, class >15, sequence >10 participants or >20 messages → split

How to Use

1. Starting a session: Read _conversation.md Table 3 (diagram type scope) to decide which diagram to create first
2. Writing PlantUML: Apply the skinparam preset from _presets.md, then check syn-safety.md for the rules relevant to your diagram type
3. After feedback: Consult _conversation.md Table 4 (signal → action) to decide whether to push a new version or reply with a question
4. Before export: Run the checklist in _design.md Heuristic 4

Reference Files

File	Description
references/_sections.md	Section definitions and ordering
references/syn-safety.md	18 rendering safety rules (Incorrect/Correct)
references/_presets.md	5 copy-paste skinparam presets per diagram type
references/_conversation.md	5 decision tables for conversation loop
references/_design.md	4 heuristics with thresholds
assets/templates/_template.md	Template for adding new rules
metadata.json	Version and reference information