pg_query · RedisNexus MCP: Risk & Policy

WHAT IT DOES

What pg_query does on RedisNexus

AI agents invoke pg_query to trigger actions in RedisNexus. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why pg_query needs a policy

This tool executes arbitrary SQL queries including INSERT, UPDATE, and DELETE operations, which can modify or destroy data. Since it supports the full range of DML operations including destructive ones (DELETE), and potentially could run DDL if not restricted, it warrants Execute classification at the highest severity.

From the tool's definition 'Execute a SQL query against PostgreSQL. Supports SELECT, INSERT, UPDATE, DELETE.'

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

pg_query Rate-limited

pg_query stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "pg_query": {
      "limits": [
        {
          "counter": "pg_query_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

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

FAQ

Questions about pg_query

What does the pg_query tool do? +

Execute a SQL query against PostgreSQL. Supports SELECT, INSERT, UPDATE, DELETE. It is categorised as a Execute tool in the RedisNexus MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on pg_query? +

Register the RedisNexus MCP server in PolicyLayer and add a rule for pg_query: 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 RedisNexus. Nothing to install.

What risk level is pg_query? +

pg_query is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit pg_query? +

Yes. Add a rate_limit block to the pg_query 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 pg_query completely? +

Set action: deny in the PolicyLayer policy for pg_query. 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 pg_query? +

pg_query is provided by the RedisNexus MCP server (rajkumar-madhu/mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

// THE FULL RECORD

pg_query is one line of RedisNexus's registry record.

The record carries the whole server: verified identity, auth posture, risk grade, every tool classified, recommended policy — re-checked continuously.

Teams ship this data inside their own products. See what a licence covers →