app_navigate

THE RISK

High Risk

Why app_navigate needs a policy

Navigation in web applications triggers code execution, including route handlers, component mounting, API calls, and state changes. While not as severe as code injection, it can alter user experience, trigger unintended workflows, or expose sensitive pages. This is categorized as Execute rather than Write because navigation is an action that triggers operations whose side effects depend on the argument (the path).

From the tool's definition Tool description states 'navigate to a path in the app'. Navigation actions that change application state and trigger external operations (page loads, route handlers, side effects) constitute execution.

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

POLICY

How to control app_navigate

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

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "app_navigate": {
      "limits": [
        {
          "counter": "app_navigate_rate",
          "window": "minute",
          "max": 10,
          "scope": "grant"
        }
      ]
    }
  }
}

app_navigate 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.

Create a free account and register React Tools — nothing to install.
Add this policy — paste it, or build it visually.
Point your MCP client (Claude, Cursor, anything) at your gateway URL.

RATE-LIMIT THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More React Tools tools

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All 20 React Tools tools →

Execute tools on other servers

Android Forensics ADB MCP Server adb_shell_command EMBA-MCP run_emba_scan Frida Game Hacking MCP remove_breakpoint Procmon request_elevation

Go deeper

High-risk tools in React Tools → Every high-risk tool this server exposes, in one view.
All high-risk MCP tools → Every high-risk tool across the catalogue, and the policy pattern that contains them.
The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Agent sandbox → Bounding what an agent can execute and where the boundary should sit.
Least privilege for MCP → Granting agents the minimum tool surface the task needs.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about app_navigate

What does the app_navigate tool do? +

List available routes or navigate to a path in the app. Call without. It is categorised as a Execute tool in the React Tools MCP Server, which means it can trigger actions or run processes. Use rate limits and argument validation.

How do I enforce a policy on app_navigate? +

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

What risk level is app_navigate? +

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

Can I rate-limit app_navigate? +

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

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

app_navigate is provided by the React Tools MCP server (mcp-fe/mcp-fe). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every React Tools tool call.

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

CHECK YOUR STACK →