input_text · React Native MCP: Risk & Policy

WHAT IT DOES

What input_text does on React Native

AI agents use input_text to create or update resources in React Native — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your React Native environment.

WHY IT NEEDS A POLICY

Why input_text needs a policy

Typing into an input field is a Write operation—it creates or modifies data within the app's UI state. The tool is confined to ASCII text input to the currently focused element, limiting its scope.

From the tool's definition input_text types into a focused input field; description states 'Type into focused input', which modifies text content in the app. This is reversible text entry, not code execution or data deletion.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

input_text Rate-limited

input_text stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "input_text": {
      "limits": [
        {
          "counter": "input_text_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches React Native, so you can run agents against it safely.

FAQ

Questions about input_text

What does the input_text tool do? +

Type into focused input. ASCII only. Use type_text for Korean/Unicode. It is categorised as a Write tool in the React Native MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on input_text? +

Register the React Native MCP server in PolicyLayer and add a rule for input_text: 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 React Native. Nothing to install.

What risk level is input_text? +

input_text is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit input_text? +

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

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

input_text is provided by the React Native MCP server (@ohah/react-native-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.