rpush · Redis MCP Server MCP: Risk & Policy

WHAT IT DOES

What rpush does on Redis MCP Server

AI agents use rpush 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 rpush needs a policy

rpush is a Redis list operation that appends elements to a list. This is a reversible write operation—elements can be removed or lists deleted if needed. It does not delete data (so not Destructive), does not execute arbitrary code (so not Execute), and does not move money (so not Financial). The ability to set expiration times does not elevate the risk beyond Write.

From the tool's definition Tool name 'rpush' and description 'Push a value onto the right of a Redis list' indicate modification of existing data structure. The phrase 'push a value onto' confirms this adds/modifies list contents reversibly.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

rpush Rate-limited

rpush 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": {
    "rpush": {
      "limits": [
        {
          "counter": "rpush_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 rpush

What does the rpush tool do? +

Push a value onto the right of a Redis list and optionally set an expiration time. 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 rpush? +

Register the Redis MCP Server MCP server in PolicyLayer and add a rule for rpush: 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 rpush? +

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

Can I rate-limit rpush? +

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

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

rpush 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.