Mermaid MCP vs Excalidraw Architect MCP

mermaid_to_excalidraw

Convert Mermaid flowchart syntax into an Excalidraw diagram. Supports the mermaid flowchart subset that AI agents commonly generate: - Directions: graph TD, LR, BT, RL - Node shapes: [text], {text}, ((text)), ([text]) - Edge types: -->, ---, -.-> ==> with |label| - Subgraphs: subgraph Title ... end Component types are auto-detected from node labels (e.g., a node labeled "PostgreSQL DB" automatically gets database styling).

modify_diagram

Modify an existing Excalidraw diagram created by this tool. Supports iterative editing: add components, remove nodes, update labels, and rewire connections - without recreating the entire diagram. IMPORTANT: Call get_diagram_info first to understand the current diagram state before making modifications. For **typed diagrams** (sequence, pyramid, bar, swimlane, ...) there is a single operation: {"op": "update_spec", "patch": {"tiers": [...], "title": "New title"}} The patch is deep-merged into the stored spec and the diagram re-rendered. Lists are replaced wholesale, so send the complete list to change one entry. The node/connection operations below apply to architecture and flowchart diagrams only.

get_diagram_info

Get a structured summary of an existing Excalidraw diagram. Call this BEFORE modify_diagram to understand what nodes and connections currently exist. The summary includes node ids, labels, component types, and the full connection topology.

export_diagram

Export an .excalidraw file to SVG or PNG image. Converts an existing .excalidraw diagram into a portable image file without requiring a browser or the Excalidraw application.

list_diagram_types

List every supported diagram type with guidance on when to use it. Call this BEFORE create_diagram when the right diagram type isn't obvious. Picking the wrong type is the most common way a diagram fails - a swimlane drawn as a flowchart loses the handoffs that were the point. Two rules worth applying whatever you pick: - Target density ~4/10. Above 9 nodes it is probably two diagrams. - Mark only 1-2 elements "focal": true. The accent color is a signal, and using it everywhere destroys it. Returns: A table of type -> family, when to use it, and when not to.

get_diagram_schema

Get the JSON schema and selection guidance for one diagram type. Call this before passing a `spec` to create_diagram for a type you have not used yet, so the payload matches on the first attempt.

kg_init

Create a new architecture knowledge graph file (markdown). The knowledge graph is the persistent source of truth for your system's services and dependencies. Diagrams are rendered *from* it.

kg_add_service

Add or update a service in the knowledge graph.

kg_remove_service

Remove a service and all dependencies touching it.

kg_link

Add a directed dependency: ``from_id`` depends on / calls ``to_id``. Both services must already exist (add them with kg_add_service first). ``style`` is one of solid/dashed/dotted/thick.

kg_unlink

Remove the dependency ``from_id`` -> ``to_id``.