Get a Flow Designer flow definition (sys_hub_flow) by sys_id, with its trigger instance(s) and ordered action steps. The flow header gives name/active/type/scope; the triggers reveal what fires the flow (e.g. their table and condition columns); the action instances list the ordered steps with the...
AI agents call get_flow_definition to retrieve information from ServiceNow MCP Server without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.
Even though get_flow_definition only reads data, uncontrolled read access leaks sensitive information and racks up API costs — an agent caught in a retry loop can make thousands of calls a minute without anyone noticing.
Attacks that exploit this kind of access
Get a Flow Designer flow definition (sys_hub_flow) by sys_id, with its trigger instance(s) and ordered action steps. The flow header gives name/active/type/scope; the triggers reveal what fires the flow (e.g. their table and condition columns); the action instances list the ordered steps with their action type and label. NOTE: the per-step input VALUES (the actual field assignments, e.g. setting a field to true) are stored separately (sys_variable_value, or the. It is categorised as a Read tool in the ServiceNow MCP Server MCP Server, which means it retrieves data without modifying state.
Register the ServiceNow MCP Server MCP server in PolicyLayer and add a rule for get_flow_definition: 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 ServiceNow MCP Server. Nothing to install.
get_flow_definition is a Read tool with low risk. Read-only tools are generally safe to allow by default.
Yes. Add a rate_limit block to the get_flow_definition 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 get_flow_definition. 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.
get_flow_definition is provided by the ServiceNow MCP Server MCP server (windoze95/servicewow-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.