pg_vacuum

Run VACUUM to reclaim storage and update visibility map. Use analyze: true to also update statistics. Verbose output goes to PostgreSQL server logs.

SERVERPostgreSQL MCP Server SOURCE@neverinfamous/postgres-mcp

High RISK CLASS

Category Execute

Parameters 00 required

Recommended Rate-limitedsee the rule below

Registry record Grade F, identity unverified Pull the record →

This record as markdown: /tools/io-github-neverinfamous-postgres-mcp/pg-vacuum.md

WHAT IT DOES

What pg_vacuum does on PostgreSQL MCP Server

AI agents invoke pg_vacuum to trigger actions in PostgreSQL MCP Server. 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.

RISK

Why pg_vacuum is rated High

VACUUM is an Execute operation because it triggers a complex server process whose effects (storage reclamation, index cleanup, visibility map updates) depend on database state and cannot be trivially undone.

From the tool's definition pg_vacuum: 'Run VACUUM' is a PostgreSQL maintenance command that executes server-side operations with side effects. The tool explicitly performs storage reclamation and visibility map updates, which are irreversible structural modifications to the database.

Attacks that exploit this kind of access

RECOMMENDED RULE

The rule that runs pg_vacuum safely

PolicyLayer is an MCP gateway: it sits between your AI agents and PostgreSQL MCP Server, and checks every tool call against a rule you set before the call runs. Nothing changes on the server itself. For pg_vacuum, this is the rule to start with:

pg_vacuum Rate-limited

pg_vacuum 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_vacuum": {
      "limits": [
        {
          "counter": "pg_vacuum_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

RATE-LIMIT THIS TOOL → Instant setup, no code required.

The button opens the PolicyLayer dashboard: create your workspace, connect PostgreSQL MCP Server, apply this rule, and every pg_vacuum call is checked against it from then on.

FAQ

Questions about pg_vacuum

What does the pg_vacuum tool do? +

Run VACUUM to reclaim storage and update visibility map. Use analyze: true to also update statistics. Verbose output goes to PostgreSQL server logs. It is categorised as a Execute tool in the PostgreSQL MCP Server 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_vacuum? +

Register the PostgreSQL MCP Server MCP server in PolicyLayer and add a rule for pg_vacuum: 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 PostgreSQL MCP Server. Nothing to install.

What risk level is pg_vacuum? +

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

Can I rate-limit pg_vacuum? +

Yes. Add a rate_limit block to the pg_vacuum 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_vacuum completely? +

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

pg_vacuum is provided by the PostgreSQL MCP Server MCP server (@neverinfamous/postgres-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

KEEP EXPLORING

What pg_vacuum does on PostgreSQL MCP Server

Why pg_vacuum is rated High

The rule that runs pg_vacuum safely

Questions about pg_vacuum

More on PostgreSQL MCP Server, and thousands of servers like it.