run_gremlin_query · Amazon MQ MCP Server MCP: Risk & Policy

WHAT IT DOES

What run_gremlin_query does on Amazon MQ MCP Server

AI agents invoke run_gremlin_query to trigger actions in Amazon MQ MCP Server. What it does depends on the arguments the agent supplies, and its effects often reach beyond the immediate call — builds kicked off, notifications sent, workflows started.

WHY IT NEEDS A POLICY

Why run_gremlin_query needs a policy

The tool allows execution of arbitrary Gremlin queries against a graph database. While Gremlin queries themselves have inherent constraints (graph traversal language rather than general-purpose code), they can modify graph state, perform complex operations, and their effects are entirely argument-dependent. This makes it an Execute classification.

From the tool's definition Tool name contains 'run' and description states 'Executes the provided Tinkerpop Gremlin against the graph' — this directly executes code (Gremlin query language) against a graph database with effects determined by the query argument.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

run_gremlin_query Rate-limited

run_gremlin_query 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.

View as policy code

policy.json

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

RATE-LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Amazon MQ MCP Server, so you can run agents against it safely.

FAQ

Questions about run_gremlin_query

What does the run_gremlin_query tool do? +

Executes the provided Tinkerpop Gremlin against the graph. It is categorised as a Execute tool in the Amazon MQ 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 run_gremlin_query? +

Register the Amazon MQ MCP Server MCP server in PolicyLayer and add a rule for run_gremlin_query: 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 Amazon MQ MCP Server. Nothing to install.

What risk level is run_gremlin_query? +

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

Can I rate-limit run_gremlin_query? +

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

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

run_gremlin_query is provided by the Amazon MQ MCP Server MCP server (awslabs.amazon-mq-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.