Import a Mermaid diagram and create an editable BPMN process
AI agents use bpmn_import_mermaid to create or update resources in MCP-BPMN Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your MCP-BPMN Server environment.
The tool imports external diagram data and generates BPMN objects programmatically, which is a Write operation (create). Severity is medium because it creates new process definitions that could be nonsensical or malicious if an AI agent imports adversarial Mermaid diagrams, but the impact is limited to the BPMN modeling space itself—not execution of actual workflows, financial transactions, or permanent system…
From the tool's definition Tool creates an editable BPMN process from imported Mermaid diagram—this is a creation operation that adds new data to the system.
Documented attack patterns abuse exactly the kind of access bpmn_import_mermaid gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and MCP-BPMN Server, and nothing reaches the server without passing your rules. This is the rule we recommend for bpmn_import_mermaid:
{
"version": "1",
"default": "deny",
"tools": {
"bpmn_import_mermaid": {
"limits": [
{
"counter": "bpmn_import_mermaid_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
} bpmn_import_mermaid 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.
Import a Mermaid diagram and create an editable BPMN process. It is categorised as a Write tool in the MCP-BPMN Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the MCP-BPMN Server MCP server in PolicyLayer and add a rule for bpmn_import_mermaid: 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 MCP-BPMN Server. Nothing to install.
bpmn_import_mermaid 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 bpmn_import_mermaid 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 bpmn_import_mermaid. 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.
bpmn_import_mermaid is provided by the MCP-BPMN Server MCP server (oisee/mcp-bpmn). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from MCP-BPMN Server, 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.
41 MCP-BPMN Server tools catalogued and risk-classified — across an index of 43,000+ MCP servers.