call_api · WikiTree MCP server MCP: Risk & Policy

WHAT IT DOES

What call_api does on WikiTree MCP server

AI agents invoke call_api to trigger actions in WikiTree 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 call_api needs a policy

This tool allows calling any arbitrary WikiTree API endpoint, not just read operations. Because it is unconstrained, it could trigger write, destructive, or other side-effect operations depending on the endpoint chosen. The open-ended nature ('any endpoint') means an AI agent could inadvertently or maliciously invoke mutating operations, making Execute the most appropriate category given the potential blast radius.

From the tool's definition "Call any WikiTree API endpoint directly" — unrestricted access to any API endpoint

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

call_api Rate-limited

call_api 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": {
    "call_api": {
      "limits": [
        {
          "counter": "call_api_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 WikiTree MCP server, so you can run agents against it safely.

FAQ

Questions about call_api

What does the call_api tool do? +

Call any WikiTree API endpoint directly. It is categorised as a Execute tool in the WikiTree 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 call_api? +

Register the WikiTree MCP server MCP server in PolicyLayer and add a rule for call_api: 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 WikiTree MCP server. Nothing to install.

What risk level is call_api? +

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

Can I rate-limit call_api? +

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

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

call_api is provided by the WikiTree MCP server MCP server (pewu/wikitree-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.