refresh_pre_aggregations

THE RISK

High Risk

Why refresh_pre_aggregations needs a policy

This tool triggers a refresh operation on pre-aggregations via a POST request, which re-computes and overwrites cached aggregated data. It is an active operation with external side effects (recomputing analytics aggregates), making it Execute. It is not purely destructive (original source data is preserved) but it does overwrite pre-aggregation caches.

From the tool's definition Refresh pre-aggregations (POST /pre-aggregations/refresh)

Documented attack patterns abuse exactly the kind of access refresh_pre_aggregations gives an agent:

POLICY

How to control refresh_pre_aggregations

PolicyLayer is an MCP gateway — it sits between your AI agents and Cube Js MCP Server, and nothing reaches the server without passing your rules. This is the rule we recommend for refresh_pre_aggregations:

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "refresh_pre_aggregations": {
      "limits": [
        {
          "counter": "refresh_pre_aggregations_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

refresh_pre_aggregations stays usable, but rate-capped — a runaway agent can't fire it dozens of times a minute. Everything else on the server is denied unless you say otherwise.

Create a free account and register Cube Js MCP Server — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RATE-LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Cube Js MCP Server tools

Execute execute_query execute_query Execute execute_query_post Executes a query against the Cube.js API using POST method (recommended for complex querie Execute refresh Trigger a refresh for the given query (POST /refresh). Execute scheduled_refresh Trigger scheduled refresh (POST /refresh/schedule or similar). Execute raw_request Generic request tool to call arbitrary Cube.js REST endpoints. Read check_health Checks the health status of the Cube.js server. Read get_schema Get the schema representation from Cube.js (GET /schema). Read get_sql Returns the generated SQL for a given query without executing it.

All 10 Cube Js MCP Server tools →

Execute tools on other servers

Android Forensics ADB MCP Server adb_shell_command EMBA-MCP run_emba_scan Frida Game Hacking MCP remove_breakpoint Procmon request_elevation

Go deeper

High-risk tools in Cube Js MCP Server → Every high-risk tool this server exposes, in one view.
All high-risk MCP tools → Every high-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Agent sandbox → Bounding what an agent can execute and where the boundary should sit.
Least privilege for MCP → Granting agents the minimum tool surface the task needs.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about refresh_pre_aggregations

What does the refresh_pre_aggregations tool do? +

Refresh pre-aggregations (POST /pre-aggregations/refresh). It is categorised as a Execute tool in the Cube Js MCP Server MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on refresh_pre_aggregations? +

Register the Cube Js MCP Server MCP server in PolicyLayer and add a rule for refresh_pre_aggregations: 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 Cube Js MCP Server. Nothing to install.

What risk level is refresh_pre_aggregations? +

refresh_pre_aggregations is a Execute tool with high risk. Execute tools should be rate-limited and have argument validation enabled.

Can I rate-limit refresh_pre_aggregations? +

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

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

refresh_pre_aggregations is provided by the Cube Js MCP Server MCP server (zsembek/cube.js-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Cube Js MCP Server tool call.

Start from Cube Js MCP Server, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →