Kroki vs Mural MCP

Kroki

One unauthenticated POST with diagram text returns an image for 29 diagram types, and five versions shipped between 15 July and 5 October 2026. Four advisories were published in July and August 2026, one an unauthenticated remote code execution on /tikz/svg, all fixed. No OpenAPI file exists, and the public instance has no terms, privacy policy or status page.

Mural MCP

Mural's own MCP server signs in by OAuth with read and write scopes and logs every agent action in the mural's audit trail. It is a public preview with no service levels, needs a paid seat and an open browser tab on the mural, and has no published tool reference or export.

Kroki

1. Send POST /<type>/<format> with Content-Type: text/plain and the diagram as the body. This avoids the deflate and base64 encoding that GET needs
2. Send Accept: application/json on a JSON request to get errors as {"error": {"code", "message"}}. With an SVG Accept header the error arrives as an image
3. Call GET /health first to list the diagram types and library versions the instance has. Mermaid, BPMN, Excalidraw and diagrams.net need companion containers
4. Run 0.32.1 or later before rendering untrusted text. Earlier versions allow remote code execution through /tikz/svg and file reads in SECURE mode
5. Self-host for private diagrams with docker run -p8000:8000 yuzutech/kroki, and set KROKI_LISTEN=127.0.0.1:8000 or a network rule, since the server has no authentication

Mural MCP

1. Ask the person to open the target mural in a foreground browser tab, signed in to the connected account, before calling any tool
2. Work on one mural at a time and name it explicitly when switching
3. Request only murals:read when the task only reads a board
4. Deletes go through without a server-side prompt. Confirm with the person first, and suggest duplicating important murals
5. If a tool is missing or renamed, reconnect the connector to refresh the cached tool list