connect_database · MCP Universal DB Client MCP

WHAT IT DOES

What connect_database does on MCP Universal DB Client

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

WHY IT NEEDS A POLICY

Why connect_database needs a policy

Connecting to a database creates a new resource and modifies the connection pool state. While not destructive or financial, it is a write-like operation that changes application state. The severity is medium because misuse could lead to resource exhaustion (many open connections) or potential access to unauthorized databases, but the impact is bounded by connection limits and authentication constraints.

From the tool's definition Tool name is 'connect_database' and description states 'Connect to a database using connection string'. The tool establishes a new database connection, which modifies the application state by adding a new connection to the connection pool.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

connect_database Rate-limited

connect_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": {
    "connect_database": {
      "limits": [
        {
          "counter": "connect_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 MCP Universal DB Client, so you can run agents against it safely.

FAQ

Questions about connect_database

What does the connect_database tool do? +

Connect to a database using connection string. It is categorised as a Write tool in the MCP Universal DB Client MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on connect_database? +

Register the MCP Universal DB Client MCP server in PolicyLayer and add a rule for connect_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 MCP Universal DB Client. Nothing to install.

What risk level is connect_database? +

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

Can I rate-limit connect_database? +

Yes. Add a rate_limit block to the connect_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 connect_database completely? +

Set action: deny in the PolicyLayer policy for connect_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 connect_database? +

connect_database is provided by the MCP Universal DB Client MCP server (izumisy/mcp-universal-db-client). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.