update_access_group · ReliaQuest GreyMatter MCP Server MCP

WHAT IT DOES

What update_access_group does on ReliaQuest GreyMatter MCP Server

AI agents use update_access_group to create or update resources in ReliaQuest GreyMatter MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your ReliaQuest GreyMatter MCP Server environment.

WHY IT NEEDS A POLICY

Why update_access_group needs a policy

This tool modifies access control configuration by updating access group definitions. While not destructive (reversible), it performs write operations on security-critical access control data. Misuse could grant unauthorized permissions or modify group memberships, affecting who can access sensitive systems.

From the tool's definition Tool name is 'update_access_group' and description indicates it is a GraphQL mutation for updating access groups. The 'mutation' keyword and 'input' variable confirm this performs data modification rather than retrieval.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

update_access_group Rate-limited

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

FAQ

Questions about update_access_group

What does the update_access_group tool do? +

Access Groups \u00b7 mutation updateAccessGroup. Variables: after, filter, first, order, after1, filter1, first1, order1, after2, filter2, first2, order2, input. Example variables: {\. It is categorised as a Write tool in the ReliaQuest GreyMatter 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 update_access_group? +

Register the ReliaQuest GreyMatter MCP Server MCP server in PolicyLayer and add a rule for update_access_group: 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 update_access_group? +

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

Can I rate-limit update_access_group? +

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

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

update_access_group 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.