insertRows · Postgresql MCP: Risk & Policy

WHAT IT DOES

What insertRows does on Postgresql

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

WHY IT NEEDS A POLICY

Why insertRows needs a policy

The insertRows tool creates new rows in a database table, which is a Write operation—it modifies data reversibly. While the tool uses parameterized queries to prevent SQL injection (a security feature), this does not change its fundamental category. The severity is medium because inserting incorrect or malicious data could corrupt the database state, but it remains reversible via deletion.

From the tool's definition Tool name is 'insertRows' and description states 'Insert one or more rows into a table'. This is a data creation/modification operation that is reversible (rows can be deleted).

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

insertRows Rate-limited

insertRows 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": {
    "insertRows": {
      "limits": [
        {
          "counter": "insertrows_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, so you can run agents against it safely.

FAQ

Questions about insertRows

What does the insertRows tool do? +

Insert one or more rows into a table using parameterized queries (safe from SQL injection). Specify rows as an array of objects where keys are column names. Optionally specify columns to return (e.g., [. It is categorised as a Write tool in the Postgresql MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on insertRows? +

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

What risk level is insertRows? +

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

Can I rate-limit insertRows? +

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

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

insertRows is provided by the Postgresql MCP server (vnikhilbuddhavarapu/postgresql-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.