AI agents use bpmn_add_lane 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 creates a new lane within a pool, which modifies the BPMN diagram structure. This is a Write operation because it creates new elements and modifies the diagram reversibly. The severity is medium because incorrect lane additions could corrupt or confuse process models, but the impact is confined to the diagram structure and can be undone.
From the tool's definition Tool name 'bpmn_add_lane' and description 'Add a lane to an existing pool' indicate creation/modification of BPMN diagram elements. This is a reversible structural change to a business process model.
Documented attack patterns abuse exactly the kind of access bpmn_add_lane 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_add_lane:
{
"version": "1",
"default": "deny",
"tools": {
"bpmn_add_lane": {
"limits": [
{
"counter": "bpmn_add_lane_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
} bpmn_add_lane 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.
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Add a lane to an existing pool. 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_add_lane: 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_add_lane 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_add_lane 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_add_lane. 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_add_lane 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.