run-vitest · Vitest MCP Server MCP: Risk & Policy

WHAT IT DOES

What run-vitest does on Vitest MCP Server

AI agents invoke run-vitest to trigger actions in Vitest 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 run-vitest needs a policy

This tool executes an external testing framework (Vitest), which runs arbitrary test code and triggers side effects dependent on test file arguments. While test execution itself is typically safe and reversible, it qualifies as Execute rather than Read because it runs code with effects that depend on supplied arguments (which test files to run).

From the tool's definition Tool name 'run-vitest' indicates execution of Vitest test suite. Server description confirms 'run Vitest tests' capability. Empty tool description reduces specificity but context is clear.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

run-vitest Rate-limited

run-vitest 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": {
    "run-vitest": {
      "limits": [
        {
          "counter": "run-vitest_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 Vitest MCP Server, so you can run agents against it safely.

FAQ

Questions about run-vitest

What does the run-vitest tool do? +

run-vitest. It is categorised as a Execute tool in the Vitest 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 run-vitest? +

Register the Vitest MCP Server MCP server in PolicyLayer and add a rule for run-vitest: 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 Vitest MCP Server. Nothing to install.

What risk level is run-vitest? +

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

Can I rate-limit run-vitest? +

Yes. Add a rate_limit block to the run-vitest 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 run-vitest completely? +

Set action: deny in the PolicyLayer policy for run-vitest. 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 run-vitest? +

run-vitest is provided by the Vitest MCP Server MCP server (madrus/vitest-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.