diagrammer

Use diagrammer to turn a small JSON spec into a clean SVG diagram. It is useful when the user wants a precise technical diagram without opening a design tool.

Install

The renderer must be installed locally:

pipx install diagrammer

Workflow

Convert the user's plain-English diagram request into a JSON spec.
Save the spec to a temporary or project file.
Render it:

diagrammer path/to/spec.json > path/to/diagram.svg

Return the SVG path to the user.

Spec Essentials

{
  "nodes": [
    {"id": "client", "type": "box", "label": "client"},
    {"id": "api", "type": "box", "label": "api"},
    {"id": "db", "type": "database", "label": "postgres"}
  ],
  "edges": [
    {"from": "client", "to": "api", "label": "request"},
    {"from": "api", "to": "db", "label": "query"}
  ]
}

Built-in node types: box, circle, text, database, stack, group, note, and custom.

Useful optional fields:

direction: "LR" or "TB"
router: "straight" or "ortho"
label on edges
style: "solid" or "dashed"
weight: "thin" or "thick"

For the full reference, run:

diagrammer prompt

When To Choose This

Use diagrammer when the output should be a checked-in SVG artifact, especially for:

README diagrams
architecture sketches
request flows
state machines
neural-net or transformer diagrams
simple data pipelines

Prefer Mermaid when the user specifically asks for Mermaid syntax or wants diagrams rendered by a Markdown platform. Prefer Excalidraw when the user wants editable hand-drawn canvas files.