Opens a schematic screenshot in draw.io with engineering annotations overlaid.
AI agents use markup_schematic to create or update resources in Drawio Engineering — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Drawio Engineering environment.
The tool creates or modifies diagram content by adding annotations to a schematic, which is a reversible write operation. It does not execute arbitrary code, delete data, or cause financial impact. The severity is medium because misuse could result in incorrect or misleading engineering annotations that might affect design reviews, though such changes are reversible.
From the tool's definition Tool opens a schematic screenshot in draw.io and overlays engineering annotations—this modifies the diagram by adding markup/annotations to existing content.
Documented attack patterns abuse exactly the kind of access markup_schematic gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Drawio Engineering, and nothing reaches the server without passing your rules. This is the rule we recommend for markup_schematic:
{
"version": "1",
"default": "deny",
"tools": {
"markup_schematic": {
"limits": [
{
"counter": "markup_schematic_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}markup_schematic stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.
Free to start. No card required.
Opens a schematic screenshot in draw.io with engineering annotations overlaid. It is categorised as a Write tool in the Drawio Engineering MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Drawio Engineering MCP server in PolicyLayer and add a rule for markup_schematic: allow, deny, rate-limit, or require approval. Point your MCP client at the PolicyLayer proxy URL and the rule is enforced on every call, before it reaches Drawio Engineering. Nothing to install.
markup_schematic is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.
Yes. Add a rate_limit block to the markup_schematic rule in your PolicyLayer policy. For example, setting max: 10 and window: 60 limits the tool to 10 calls per minute. Rate limits are tracked per agent session and reset automatically.
Set action: deny in the PolicyLayer policy for markup_schematic. The AI agent will receive a policy violation error and cannot call the tool. You can also include a reason field to explain why the tool is blocked.
markup_schematic is provided by the Drawio Engineering MCP server (rfingadam/drawio-engineering-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Drawio Engineering, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.
Free to start. No card required.
10 Drawio Engineering tools catalogued and risk-classified — across an index of 43,000+ MCP servers.