redis_decr · Multi-Database MCP Server MCP: Risk & Policy

WHAT IT DOES

What redis_decr does on Multi-Database MCP Server

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

WHY IT NEEDS A POLICY

Why redis_decr needs a policy

This tool modifies an existing Redis key's integer value by decrementing it. This is a reversible write operation (the value can be incremented back), not destructive since no data is deleted. Severity is medium because misuse could corrupt application state dependent on Redis counters (e.g., rate limiters, counters, stock levels).

From the tool's definition Decrement the integer value of a key by 1 (requires FULL mode)

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

redis_decr Rate-limited

redis_decr 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": {
    "redis_decr": {
      "limits": [
        {
          "counter": "redis_decr_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 Multi-Database MCP Server, so you can run agents against it safely.

FAQ

Questions about redis_decr

What does the redis_decr tool do? +

Decrement the integer value of a key by 1 (requires FULL mode). It is categorised as a Write tool in the Multi-Database 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 redis_decr? +

Register the Multi-Database MCP Server MCP server in PolicyLayer and add a rule for redis_decr: 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 Multi-Database MCP Server. Nothing to install.

What risk level is redis_decr? +

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

Can I rate-limit redis_decr? +

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

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

redis_decr is provided by the Multi-Database MCP Server MCP server (nam088/mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.