set_function_prototype · Ghidra MCP: Risk & Policy

WHAT IT DOES

What set_function_prototype does on GhidraMCP

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

WHY IT NEEDS A POLICY

Why set_function_prototype needs a policy

This tool creates or modifies data (function prototypes) reversibly within a reverse engineering analysis project. It does not execute external code, delete data permanently, move money, or trigger irreversible operations. The modification is scoped to project metadata and can be undone or overwritten, making it Write rather than Execute or Destructive.

From the tool's definition Tool name is 'set_function_prototype' and description states it 'Set a function's prototype.' This modifies function metadata within a Ghidra project.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

set_function_prototype Rate-limited

set_function_prototype 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_function_prototype": {
      "limits": [
        {
          "counter": "set_function_prototype_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 GhidraMCP, so you can run agents against it safely.

FAQ

Questions about set_function_prototype

What does the set_function_prototype tool do? +

Set a function's prototype. It is categorised as a Write tool in the GhidraMCP 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_function_prototype? +

Register the Ghidra MCP server in PolicyLayer and add a rule for set_function_prototype: 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 GhidraMCP. Nothing to install.

What risk level is set_function_prototype? +

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

Can I rate-limit set_function_prototype? +

Yes. Add a rate_limit block to the set_function_prototype 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_function_prototype completely? +

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

set_function_prototype is provided by the Ghidra MCP server (pr0cf5/ghidramcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.