elfa_set_auth · CG Alpha MCP: Risk & Policy

WHAT IT DOES

What elfa_set_auth does on CG Alpha MCP

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

WHY IT NEEDS A POLICY

Why elfa_set_auth needs a policy

This tool creates or modifies API authentication credentials/headers, which is a reversible write operation that affects how subsequent API calls are authenticated. While it doesn't directly modify data or execute queries, it changes system configuration in a way that could enable unauthorized access or privilege escalation if misused by an AI agent (e.g., setting a malicious key).

From the tool's definition Tool name 'elfa_set_auth' and description 'Set ELFA API auth' with parameters for key, headerName, and scheme indicate this modifies authentication configuration state.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

elfa_set_auth Rate-limited

elfa_set_auth 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": {
    "elfa_set_auth": {
      "limits": [
        {
          "counter": "elfa_set_auth_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 CG Alpha MCP, so you can run agents against it safely.

FAQ

Questions about elfa_set_auth

What does the elfa_set_auth tool do? +

Set ELFA API auth. Params: key (string), headerName (Authorization|x-elfa-api-key), scheme (e.g., Bearer). It is categorised as a Write tool in the CG Alpha MCP MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on elfa_set_auth? +

Register the CG Alpha MCP server in PolicyLayer and add a rule for elfa_set_auth: 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 CG Alpha MCP. Nothing to install.

What risk level is elfa_set_auth? +

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

Can I rate-limit elfa_set_auth? +

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

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

elfa_set_auth is provided by the CG Alpha MCP server (jcf0/cg-alpha-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.