disconnect_database · PostgreSQL MCP Server MCP

WHAT IT DOES

What disconnect_database does on PostgreSQL MCP Server

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

WHY IT NEEDS A POLICY

Why disconnect_database needs a policy

Disconnecting from a database is a reversible operation that modifies the connection state but does not alter, delete, or destroy persisted data. It is not destructive (no data loss), not financial, and not execution of arbitrary code. While it could be considered a side effect, it falls under Write category as a reversible state modification.

From the tool's definition Tool name 'disconnect_database' and description 'Disconnect from the current PostgreSQL database' indicate a state-altering operation that closes an active database connection.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

disconnect_database Rate-limited

disconnect_database 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": {
    "disconnect_database": {
      "limits": [
        {
          "counter": "disconnect_database_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 PostgreSQL MCP Server, so you can run agents against it safely.

FAQ

Questions about disconnect_database

What does the disconnect_database tool do? +

Disconnect from the current PostgreSQL database. It is categorised as a Write tool in the PostgreSQL MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on disconnect_database? +

Register the PostgreSQL MCP Server MCP server in PolicyLayer and add a rule for disconnect_database: 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 disconnect_database? +

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

Can I rate-limit disconnect_database? +

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

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

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