| name | mermaid-diagramming |
| type | standard |
| depth | extended |
| description | Creates Mermaid v11+ diagrams with ELK layout and YAML frontmatter. Covers 22 diagram types: flowchart, mindmap, block, sequence, journey, state, ER, class, requirement, pie, quadrant, sankey, xy, radar, gantt, treemap, C4, architecture, packet, timeline, gitgraph, kanban. Use when visualizing: logic flow, interactions, state machines, data models, charts, system architecture, or any diagram requiring theming, classDef styling, or accessibility. |
[H1][MERMAID-DIAGRAMMING]
Dictum: Modern Mermaid syntax produces consistent, styled diagrams.
Mermaid v11+ diagram creation with frontmatter YAML, ELK layout, Dracula palette. 22 diagram types across 5 semantic categories.
Scope:
- Create: New diagrams from requirements. Select category, load syntax reference, apply styling.
- Reference: Syntax lookup for nodes, edges, relationships, charts, architecture.
Domain Navigation:
- [CONFIG] — Frontmatter YAML, ELK 5-phase layout, direction, limits. Load FIRST for all diagrams.
- [STYLING] — Theme presets, themeVariables, classDef, linkStyle, palette. Load for visual customization.
- [GRAPH] — Flowchart, mindmap, block. Load for: decision trees, hierarchies, system decomposition.
- [INTERACTION] — Sequence, journey. Load for: protocols, request-response, user experience.
- [MODELING] — State, ER, class, requirement. Load for: FSM, data models, OOP structure, traceability.
- [CHARTS] — Pie, quadrant, sankey, xy, radar, gantt, treemap. Load for: data visualization, project timelines.
- [ARCHITECTURE] — C4, architecture-beta, packet-beta, timeline, gitgraph, kanban. Load for: system views, infrastructure, network protocols, version control flow, project boards.
[1][INSTRUCTIONS]
Dictum: Progressive loading optimizes context.
Required Tasks:
- Read →global-config.md: Frontmatter YAML, ELK layout (required for ALL diagrams).
- Read →styling.md: Theme, classDef, palette.
- Select diagram category per §2 table, load corresponding syntax reference.
[REFERENCE]: →index.md — Complete file listing.
Guidance:
Config First— Frontmatter YAML must precede diagram declaration. Mermaid parses config before nodes.ELK Layout— ELK provides comprehensive graph layout via five algorithmic phases: cycle breaking, layering, crossing minimization, node placement, edge routing.
Best-Practices:
- Load Sequence — global-config.md → styling.md → {category}.md → compose. Never skip configuration.
- Frontmatter Only —
%%{init:...}%%directives deprecated v10.5.0. Use YAML frontmatter exclusively.
[2][DIAGRAM_SELECTION]
Dictum: Category determines semantic structure.
| [CATEGORY] | [TYPES] | [REFERENCE] |
|---|---|---|
| Graph | flowchart, mindmap, block | →graph.md |
| Interaction | sequence, journey | →interaction.md |
| Modeling | state, ER, class, requirement | →modeling.md |
| Charts | pie, quadrant, sankey, xy, radar, gantt, treemap | →charts.md |
| Architecture | C4, architecture, packet, timeline, gitgraph, kanban | →architecture.md |
Type Headers:
| [INDEX] | [TYPE] | [HEADER] | [DIR] | [CATEGORY] |
|---|---|---|---|---|
| [1] | Flowchart | flowchart LR |
LR | Graph |
| [2] | Mindmap | mindmap |
— | Graph |
| [3] | Block | block-beta |
— | Graph |
| [4] | Sequence | sequenceDiagram |
TB | Interaction |
| [5] | Journey | journey |
— | Interaction |
| [6] | State | stateDiagram-v2 |
TB | Modeling |
| [7] | ER | erDiagram |
LR | Modeling |
| [8] | Class | classDiagram |
TB | Modeling |
| [9] | Requirement | requirementDiagram |
— | Modeling |
| [10] | Pie | pie |
— | Charts |
| [11] | Quadrant | quadrantChart |
— | Charts |
| [12] | Sankey | sankey-beta |
— | Charts |
| [13] | XY | xychart-beta |
— | Charts |
| [14] | Radar | radar-beta |
— | Charts |
| [15] | Gantt | gantt |
— | Charts |
| [16] | Treemap | treemap-beta |
— | Charts |
| [17] | C4 | C4Context |
— | Architecture |
| [18] | Architecture | architecture-beta |
— | Architecture |
| [19] | Packet | packet-beta |
— | Architecture |
| [20] | Timeline | timeline |
— | Architecture |
| [21] | GitGraph | gitGraph |
— | Architecture |
| [22] | Kanban | kanban |
— | Architecture |
Guidance:
LR Default— Horizontal flow matches reading order. Sequence/State force TB implicitly.Beta Status— block, sankey, xy, radar, treemap, architecture, packet, kanban are beta; syntax may change.
Best-Practices:
- Category Match — Select by primary concern: flow→Graph, time→Interaction, structure→Modeling, data→Charts, system→Architecture.
[3][VALIDATION]
Dictum: Gates prevent rendering failures.
[VERIFY] Before diagram creation:
- Frontmatter: valid YAML with
config:key (before diagram declaration). - Direction: LR for flowchart/ER, implicit TB for sequence/state.
- Reserved words avoided:
end,default,subgraph,classin node IDs. - classDef: placed at diagram end, after node definitions.
- Accessibility: accTitle/accDescr present after diagram type.
[REFERENCE]: →validation.md — Full validation checklists and anti-patterns.