set_config · GB MCP: Risk & Policy

WHAT IT DOES

What set_config does on GBMCP

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

WHY IT NEEDS A POLICY

Why set_config needs a policy

This tool creates or modifies configuration data reversibly. It does not delete data (Destructive), execute arbitrary code (Execute), move money (Financial), or merely read data (Read). Configuration updates are typical Write operations.

From the tool's definition Tool name 'set_config' and description 'Update GBMCP configuration for later tool calls' indicates modification of configuration state.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_config Rate-limited

set_config 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": {
    "set_config": {
      "limits": [
        {
          "counter": "set_config_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 GBMCP, so you can run agents against it safely.

FAQ

Questions about set_config

What does the set_config tool do? +

Update GBMCP configuration for later tool calls. It is categorised as a Write tool in the GBMCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on set_config? +

Register the GB MCP server in PolicyLayer and add a rule for set_config: 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 GBMCP. Nothing to install.

What risk level is set_config? +

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

Can I rate-limit set_config? +

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

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

set_config is provided by the GB MCP server (loydgik/gbmcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.