High Risk →

start_app

启动应用

How to control start_app ↓

What start_app does on Adb

AI agents invoke start_app to trigger actions in Adb. 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.

High Risk

Why start_app needs a policy

This tool executes an operation on a remote Android device by launching an application. While not destructive (the app can be stopped), it has Execute semantics because it triggers external application behavior whose effects depend on which app is started. An agent could misuse this to launch malicious apps, access sensitive device features, or trigger unwanted operations.

From the tool's definition Tool name 'start_app' with description '启动应用' (start application in Chinese) performs an action that triggers execution on a remote Android device. The server description confirms this enables 'app management' and 'remote control of Android devices via ADB'.

Documented attack patterns abuse exactly the kind of access start_app gives an agent:

How to control start_app

PolicyLayer is an MCP gateway — it sits between your AI agents and Adb, and nothing reaches the server without passing your rules. This is the rule we recommend for start_app:

policy.json
{
  "version": "1",
  "default": "deny",
  "tools": {
    "start_app": {
      "limits": [
        {
          "counter": "start_app_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

start_app 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.

  1. Create a free account and register Adb — nothing to install.
  2. Add this policy — paste it, or build it visually.
  3. Point your MCP client (Claude, Cursor, anything) at your gateway URL.
RATE-LIMIT THIS TOOL →

Free to start. No card required.

Related tools and policies

Go deeper

Questions about start_app

What does the start_app tool do? +

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

How do I enforce a policy on start_app? +

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

What risk level is start_app? +

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

Can I rate-limit start_app? +

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

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

start_app is provided by the Adb MCP server (wolfcoming/adb_mcp_server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Adb tool call.

Start from Adb, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

Free to start. No card required.

48 Adb tools catalogued and risk-classified — across an index of 43,000+ MCP servers.

// GET IN TOUCH

Have a question or want to learn more? Send us a message.

Message sent.

We'll get back to you soon.