create_schema · Awslabs Valkey MCP: Risk & Policy

WHAT IT DOES

What create_schema does on Awslabs Valkey

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

WHY IT NEEDS A POLICY

Why create_schema needs a policy

Creating a schema in an ElastiCache/MemoryDB context modifies the data structure configuration of the cache/database, which is a reversible write operation. It does not delete data (Destructive), execute arbitrary code (Execute), or involve financial transactions (Financial). The empty description reduces confidence but the 'create_' prefix and server context clearly indicate a write operation rather than a read.

From the tool's definition Tool name is 'create_schema' which indicates creation of a new schema structure. Description is empty, limiting confidence.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

create_schema Rate-limited

create_schema 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": {
    "create_schema": {
      "limits": [
        {
          "counter": "create_schema_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 Awslabs Valkey, so you can run agents against it safely.

FAQ

Questions about create_schema

What does the create_schema tool do? +

create_schema. It is categorised as a Write tool in the Awslabs Valkey MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on create_schema? +

Register the Awslabs Valkey MCP server in PolicyLayer and add a rule for create_schema: 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 Awslabs Valkey. Nothing to install.

What risk level is create_schema? +

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

Can I rate-limit create_schema? +

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

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

create_schema is provided by the Awslabs Valkey MCP server (awslabs.valkey-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.