stop_task · Yaver MCP: Risk & Policy

WHAT IT DOES

What stop_task does on Yaver

AI agents invoke stop_task to trigger actions in Yaver. 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.

PARAMETERS

Parameter	Type	Required	Description
`task_id`	string	Yes	The task ID to stop

Parameters from the server's own tool schema.

WHY IT NEEDS A POLICY

Why stop_task needs a policy

stop_task triggers real processes with real consequences. An agent gone sideways doesn't fire it once — it starts dozens of builds, sends mass notifications, or burns through compute before anyone looks up.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

stop_task Rate-limited

stop_task 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": {
    "stop_task": {
      "limits": [
        {
          "counter": "stop_task_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 Yaver, so you can run agents against it safely.

FAQ

Questions about stop_task

What does the stop_task tool do? +

Stop a running task. It is categorised as a Execute tool in the Yaver MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

What parameters does stop_task accept? +

stop_task accepts 1 parameter: task_id. Required: task_id. The full parameter table on this page comes from the server's own tool schema.

How do I enforce a policy on stop_task? +

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

What risk level is stop_task? +

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

Can I rate-limit stop_task? +

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

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

stop_task is provided by the Yaver MCP server (yaver-cli). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.