diagrammer
Render clean blueprint-style SVG diagrams from JSON specs. Use when users ask to draw, sketch, or diagram a request flow, neural net, transformer block, system architecture, state machine, data pipeline, or any node-and-edge technical visual they want as an SVG for docs, READMEs, posts, or slides.
the manual
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"labelon edgesstyle:"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.

