graphql_query · ReliaQuest GreyMatter MCP Server MCP

WHAT IT DOES

What graphql_query does on ReliaQuest GreyMatter MCP Server

AI agents invoke graphql_query to trigger actions in ReliaQuest GreyMatter 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 graphql_query needs a policy

The server description explicitly labels this tool an 'escape hatch', strongly suggesting it allows arbitrary GraphQL query/mutation execution. GraphQL can perform both reads and writes (mutations), and as a generic escape hatch it likely bypasses normal guardrails.

From the tool's definition Tool name 'graphql_query' combined with server description explicitly calling it a 'generic graphql_query escape hatch' — implies arbitrary query execution capability

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

graphql_query Rate-limited

graphql_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": {
    "graphql_query": {
      "limits": [
        {
          "counter": "graphql_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 ReliaQuest GreyMatter MCP Server, so you can run agents against it safely.

FAQ

Questions about graphql_query

What does the graphql_query tool do? +

graphql_query. It is categorised as a Execute tool in the ReliaQuest GreyMatter 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 graphql_query? +

Register the ReliaQuest GreyMatter MCP Server MCP server in PolicyLayer and add a rule for graphql_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 ReliaQuest GreyMatter MCP Server. Nothing to install.

What risk level is graphql_query? +

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

Can I rate-limit graphql_query? +

Yes. Add a rate_limit block to the graphql_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 graphql_query completely? +

Set action: deny in the PolicyLayer policy for graphql_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 graphql_query? +

graphql_query is provided by the ReliaQuest GreyMatter MCP Server MCP server (space-c0wboy/reliaquest-greymatter-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.