supabase_insert · Supabase MCP Server MCP: Risk & Policy

WHAT IT DOES

What supabase_insert does on Supabase MCP Server

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

WHY IT NEEDS A POLICY

Why supabase_insert needs a policy

This tool creates new data entries in a Supabase database table. While inserts are reversible (records can be deleted), they represent persistent modifications to the database state. The tool is Write-category because it modifies data without destroying existing records.

From the tool's definition Tool description explicitly states 'Insert one or multiple records into a Supabase table' - insert operations create new data records in the database.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

supabase_insert Rate-limited

supabase_insert 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": {
    "supabase_insert": {
      "limits": [
        {
          "counter": "supabase_insert_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 Supabase MCP Server, so you can run agents against it safely.

FAQ

Questions about supabase_insert

What does the supabase_insert tool do? +

Insert one or multiple records into a Supabase table. It is categorised as a Write tool in the Supabase 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 supabase_insert? +

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

What risk level is supabase_insert? +

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

Can I rate-limit supabase_insert? +

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

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

supabase_insert is provided by the Supabase MCP Server MCP server (sweir1/supabase-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.