task_submit · Willow MCP: Risk & Policy

WHAT IT DOES

What task_submit does on Willow

AI agents invoke task_submit to trigger actions in Willow. 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 task_submit needs a policy

This tool submits tasks for execution in a sandboxed environment. Despite the sandbox (bubblewrap), it triggers external code/command execution whose effects depend on the submitted task arguments. Execution of arbitrary tasks carries high blast radius risk even within a sandbox, as sandbox escapes or resource exhaustion are possible.

From the tool's definition 'Submit a task to the Kart sandboxed execution queue. Kart runs the task in a bubblewrap'

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

task_submit Rate-limited

task_submit 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": {
    "task_submit": {
      "limits": [
        {
          "counter": "task_submit_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 Willow, so you can run agents against it safely.

FAQ

Questions about task_submit

What does the task_submit tool do? +

Submit a task to the Kart sandboxed execution queue. Kart runs the task in a bubblewrap. It is categorised as a Execute tool in the Willow MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on task_submit? +

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

What risk level is task_submit? +

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

Can I rate-limit task_submit? +

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

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

task_submit is provided by the Willow MCP server (rudi193-cmd/willow-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.