Delete a site-level rule
AI agents call delete_site_rule to permanently remove resources in Fastly NGWAF MCP Server — typically in cleanup and lifecycle workflows. It does its job in a single call, and there is no undo.
This tool irreversibly removes a site-level WAF rule, which is a security configuration that cannot be automatically recovered. Deletion of security rules has a high blast radius: an AI agent misusing this could disable important protections, expose the application to attacks, or violate compliance requirements. This is unambiguously Destructive (worse than Write, which is reversible).
From the tool's definition Tool name is 'delete_site_rule' and description states 'Delete a site-level rule' — the verb 'Delete' explicitly indicates irreversible removal of data.
Attacks that exploit this kind of access
Delete a site-level rule. It is categorised as a Destructive tool in the Fastly NGWAF MCP Server MCP Server, which means it can permanently delete or destroy data. Block by default and require explicit approval.
Register the Fastly NGWAF MCP Server MCP server in PolicyLayer and add a rule for delete_site_rule: 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 Fastly NGWAF MCP Server. Nothing to install.
delete_site_rule is a Destructive tool with critical risk. Critical-risk tools should be blocked by default and only enabled with explicit human approval.
Yes. Add a rate_limit block to the delete_site_rule 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 delete_site_rule. 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.
delete_site_rule is provided by the Fastly NGWAF MCP Server MCP server (purpleax/fastlymcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Every MCP server has a record like this.
Type a name, get the same breakdown: verified identity, auth posture, risk grade, capabilities, recommended policy.
Teams ship this data inside their own products. See what a licence covers →