enable_coverage · MCPEmulate MCP: Risk & Policy

WHAT IT DOES

What enable_coverage does on MCPEmulate

AI agents invoke enable_coverage to trigger actions in MCPEmulate. 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 enable_coverage needs a policy

Enabling code coverage tracking modifies the runtime behavior of the emulator by instrumenting execution, which is an active operational change rather than a passive read. It triggers ongoing monitoring of code execution paths within an emulation session. This falls under Execute as it initiates an active process that affects how the emulated CPU runs code.

From the tool's definition Enable basic-block level code coverage tracking — activates runtime instrumentation that hooks into the emulator's execution engine to track which basic blocks are executed.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

enable_coverage Rate-limited

enable_coverage 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": {
    "enable_coverage": {
      "limits": [
        {
          "counter": "enable_coverage_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 MCPEmulate, so you can run agents against it safely.

FAQ

Questions about enable_coverage

What does the enable_coverage tool do? +

Enable basic-block level code coverage tracking. It is categorised as a Execute tool in the MCPEmulate MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on enable_coverage? +

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

What risk level is enable_coverage? +

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

Can I rate-limit enable_coverage? +

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

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

enable_coverage is provided by the MCPEmulate MCP server (labguy94/mcpemulate). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.