AI agents use create_role to create or update resources in Mysql — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Mysql environment.
The tool creates a new role, which is a reversible modification to the database's access control system. While roles are structural changes, they do not directly delete or destroy data (hence not Destructive), and the operation itself is not a read-only query (hence not Read). It is fundamentally a Write operation that creates new database objects.
From the tool's definition Tool name 'create_role' and description 'Create a new role (MySQL 8.0+)' indicate database schema modification that adds a new access control object. This is write operation on database metadata.
Documented attack patterns abuse exactly the kind of access create_role gives an agent:
PolicyLayer is an MCP gateway — it sits between your AI agents and Mysql, and nothing reaches the server without passing your rules. This is the rule we recommend for create_role:
{
"version": "1",
"default": "deny",
"tools": {
"create_role": {
"limits": [
{
"counter": "create_role_rate",
"window": "minute",
"max": 30,
"scope": "grant"
}
]
}
}
}create_role 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.
Create a new role (MySQL 8.0+). It is categorised as a Write tool in the Mysql MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.
Register the Mysql MCP server in PolicyLayer and add a rule for create_role: 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 Mysql. Nothing to install.
create_role 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 create_role 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 create_role. 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.
create_role is provided by the Mysql MCP server (mukul975/mysql-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.
Start from Mysql, 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.
233 Mysql tools catalogued and risk-classified — across an index of 43,000+ MCP servers.