zadd · Redis MCP Server MCP: Risk & Policy

WHAT IT DOES

What zadd does on Redis MCP Server

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

WHY IT NEEDS A POLICY

Why zadd needs a policy

In Redis, ZADD adds one or more members to a sorted set, or updates scores of existing members. This is a write operation that creates or modifies data reversibly (members can be removed later). The description is empty, so confidence is reduced, but the well-known Redis command name strongly implies write behavior. Severity is medium as misuse could pollute sorted set data but is reversible.

From the tool's definition Tool name 'zadd' corresponds to the Redis ZADD command, which adds or updates members in a sorted set.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

zadd Rate-limited

zadd 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": {
    "zadd": {
      "limits": [
        {
          "counter": "zadd_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 Redis MCP Server, so you can run agents against it safely.

FAQ

Questions about zadd

What does the zadd tool do? +

zadd. It is categorised as a Write tool in the Redis 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 zadd? +

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

What risk level is zadd? +

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

Can I rate-limit zadd? +

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

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

zadd is provided by the Redis MCP Server MCP server (yuchenhui/mcp-redis). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.