vanna_generate_sql · PostGIS Yukon MCP: Risk & Policy

WHAT IT DOES

What vanna_generate_sql does on PostGIS Yukon MCP

AI agents use vanna_generate_sql to create or update resources in PostGIS Yukon MCP — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your PostGIS Yukon MCP environment.

WHY IT NEEDS A POLICY

Why vanna_generate_sql needs a policy

An AI agent can call vanna_generate_sql faster than any human can review — one bad instruction and it creates or modifies resources in PostGIS Yukon MCP by the hundred, each call as confident as the last.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

vanna_generate_sql Rate-limited

vanna_generate_sql 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.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "vanna_generate_sql": {
      "limits": [
        {
          "counter": "vanna_generate_sql_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches PostGIS Yukon MCP, so you can run agents against it safely.

FAQ

Questions about vanna_generate_sql

What does the vanna_generate_sql tool do? +

vanna_generate_sql. It is categorised as a Write tool in the PostGIS Yukon MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on vanna_generate_sql? +

Register the PostGIS Yukon MCP server in PolicyLayer and add a rule for vanna_generate_sql: 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 PostGIS Yukon MCP. Nothing to install.

What risk level is vanna_generate_sql? +

vanna_generate_sql is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit vanna_generate_sql? +

Yes. Add a rate_limit block to the vanna_generate_sql 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.

How do I block vanna_generate_sql completely? +

Set action: deny in the PolicyLayer policy for vanna_generate_sql. 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.

What MCP server provides vanna_generate_sql? +

vanna_generate_sql is provided by the PostGIS Yukon MCP server (zmgiser/postgis_yukon_mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.