add_key · Ast Editor MCP: Risk & Policy

WHAT IT DOES

What add_key does on Ast Editor

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

WHY IT NEEDS A POLICY

Why add_key needs a policy

This tool creates or modifies code structure by adding a key, which is a reversible write operation. It does not delete data (would be Destructive), execute arbitrary code (would be Execute), or handle financial operations.

From the tool's definition Tool name 'add_key' with sibling tools like 'add_field', 'add_import', 'add_method', 'add_parameter', 'add_top_level', and 'append_to_array' indicates structural code modification.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

add_key Rate-limited

add_key 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": {
    "add_key": {
      "limits": [
        {
          "counter": "add_key_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 Ast Editor, so you can run agents against it safely.

FAQ

Questions about add_key

What does the add_key tool do? +

add_key. It is categorised as a Write tool in the Ast Editor MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on add_key? +

Register the Ast Editor MCP server in PolicyLayer and add a rule for add_key: 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 Ast Editor. Nothing to install.

What risk level is add_key? +

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

Can I rate-limit add_key? +

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

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

add_key is provided by the Ast Editor MCP server (kambleakash0/ast-editor). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.