capture_live · Tshark MCP: Risk & Policy

WHAT IT DOES

What capture_live does on Tshark

AI agents invoke capture_live to trigger actions in Tshark. 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 capture_live needs a policy

Based on the server description mentioning live capture capabilities and the tool name 'capture_live', this tool almost certainly initiates a live network packet capture on a network interface. This is an Execute-category action as it triggers an external operation (network sniffing) with significant blast radius — it could capture sensitive credentials, session tokens, or private communications.

From the tool's definition Tool name 'capture_live' on a server described as supporting 'live capture' via TShark; description is empty and uninformative.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

capture_live Rate-limited

capture_live 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": {
    "capture_live": {
      "limits": [
        {
          "counter": "capture_live_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 Tshark, so you can run agents against it safely.

FAQ

Questions about capture_live

What does the capture_live tool do? +

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

How do I enforce a policy on capture_live? +

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

What risk level is capture_live? +

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

Can I rate-limit capture_live? +

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

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

capture_live is provided by the Tshark MCP server (ouonet/tshark-mcp). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.