common:database
A persistent structured data store. It is the canonical database type; add common@0.1.0 to the model's libraries before using it.
Common tokens
The common library holds tokens that retain the same meaning across architecture notations. It contains two component types, three appearance-only tokens, and one ordinal annotation.
Semantic component types
Section titled “Semantic component types”
common:user
A human participant who interacts with a software system. It is narrower than an external actor, which may also be another system.
Presentation tokens
Section titled “Presentation tokens”These applied tokens affect rendering only. They do not turn a component into a decision, change its domain role, or assert that an ordinal is time-based.
common:visual.decision-hexagon
A wide six-sided component appearance.
common:visual.diamond
A compact diamond component appearance.
common:visual.parallelogram
A right-leaning component appearance.
common:ordinal-marker
An annotation with a required positive ordinal value.
Evidence boundary
Section titled “Evidence boundary”The common library records portable meaning, not every shape or label found in a diagram. Cross-format review found direct support for the database and human-user meanings in Mermaid C4 and draw.io C4 examples. A generic database glyph, a generic actor, or a visual group is not enough to infer storage, humanity, ownership, deployment, or a new common token.
This boundary keeps semantic tokens separate from renderer and layout policy. Renderer mappings may reuse the SVG assets shown above; the mapping does not change a token’s architectural meaning.