Assisted Generation

Provider Contract

public interface IDiagramAssistant
{
    string Name { get; }
    DiagramSuggestion Generate(DiagramRequest request);
}

A DiagramSuggestion carries a DiagramDto that loads straight into the canvas, plus an explanation and any warnings. Because it produces the same DTO the serializer uses, generated diagrams can be edited, saved and executed like any other.

Flowchart DSL

The built-in assistant understands a compact description. Nodes are created on first mention, types are inferred or declared, and edges carry optional labels:

Start(start) "Start" -> Receive "Receive order" -> Valid(decision) "Valid?"
Valid -> Pay "Process payment" : yes
Valid -> Notify "Notify customer" : no
Pay -> Ship "Ship order" -> End(end) "End"
Notify -> End

• Types: start, end, process, decision, io, document, data, delay, manual, subprocess and more.
• Start/End are inferred from the node name when no type is given.
• Lines starting with # or // are comments.
• The result is laid out top-down by rank, with branches spread across rows.

Mind-Map Outlines

Indentation is all a mind map needs — the first line is the central topic and each level of indentation becomes a ring of the radial layout:

Product strategy
  Customers
    Personas
    Feedback
  Pricing
  Roadmap

Provider Registry

DiagramAssistantRegistry tries providers in order and falls back, so an LLM assistant can be tried first and the offline rule-based assistant guarantees a result:

var registry = new DiagramAssistantRegistry();          // rule-based assistant by default
registry.Register(new MyLlmAssistant(), priority: 0);   // tried first

var suggestion = registry.Generate(new DiagramRequest
{
    Prompt = "Start -> Validate \"Check input\" -> End",
    MaxNodes = 40
});

manager.LoadFromDto(suggestion.Diagram);

DSL and Assistant Types

The offline assistant parses a small DSL into a graph and then materializes components. These types are the parser surface, useful for validation and tooling.

RuleBasedDiagramAssistant

Offline, deterministic diagram assistant. Understands the flowchart DSL (see FlowchartDslParser) and indentation-based mind-map outlines (see MindMapDslParser), lays the result out, and produces a DiagramDto ready for DrawingManager.LoadFromDto.

FlowchartDslParser

Parses a compact flowchart DSL into a graph and lays it out top-down. Grammar (one statement per line): node ["(type)"] ["title"] ["->" node ...] [": edge label"] Examples: Start(start) "Start" -> Receive "Receive order" -> Valid(decision) "Valid?" Valid -> Process "Process payment" : yes Valid -> Notify "Notify customer" : no Process -> End(end) "End" Lines starting with # or // are comments. Node names are case-insensitive; a node is created on first mention and reused afterwards.

DslGraph

Parsed graph of nodes and edges with warnings.

DslNode

A parsed DSL node with layout geometry.

DslEdge

A parsed DSL edge.

MindMapDslParser

Parses an indentation-based outline into a mind-map tree and lays it out radially. Tabs count as four spaces. Blank lines are ignored; lines starting with # or // are comments.

MindMapDslNode

A parsed mind-map node with radial layout geometry.