discover

THE RISK

Low Risk

Why discover needs a policy

The tool retrieves information about system configuration (targets, skills, webhooks, memories, wiki pages, vaults). While this is informational only, the sensitivity is elevated to medium severity because discovering system architecture, credentials storage mechanisms (vaults), and integration points (webhooks, targets) could enable follow-on attacks.

From the tool's definition Tool description states it 'returns targets, skills, webhooks, memories, wiki pages, and vaults' — all retrieval/query operations with no modification or execution semantics. Named as an alias for 'bootstrap' which enumerates available resources.

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

POLICY

How to control discover

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

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "discover": {}
  }
}

discover is read-only, so it stays allowed — but everything else on the server is denied unless you say otherwise.

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

CAP THIS TOOL →

Free to start. No card required.

EXPLORE

Related tools and policies

More Shellgate tools

Destructive memory_delete Delete a memory that is outdated, incorrect, or superseded. Prefer updating (delete + add) Destructive org_skill_delete Delete a shared organization skill from Shellgate Destructive wiki_delete_page Archive a wiki page (soft delete). Sets status to Execute ssh_exec Execute a command on an SSH target. If the response has status Execute api_request Proxy an HTTP request through the gateway to an upstream API target. If the response has s Execute blind_type Type a sensitive vault field value using keyboard events. The target field must be focused Write webhook_ack Acknowledge processed webhook events Write blind_fill Fill a sensitive vault field into a browser element via CSS selector. The secret never app

All 31 Shellgate tools →

Read tools on other servers

M-Team MCP Server get_torrent_detail YouTube MCP Server search_channel Android Forensics ADB MCP Server parse_browser_history 0xarchive web3_challenge

Go deeper

The MCP Attack Database → Documented attack patterns against MCP deployments — and the policies that stop them.
Data exfiltration → How read access becomes an exfiltration channel when chained with untrusted content.
MCP token cost → What connecting this server costs in context-window tokens on every request.
Rate Limiting MCP Tool Calls: A Practical Guide →
MCP Security: Why Prompt Guardrails Aren't Enough →

FAQ

Questions about discover

What does the discover tool do? +

Alias for bootstrap — returns targets, skills, webhooks, memories, wiki pages, and vaults. It is categorised as a Read tool in the Shellgate MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on discover? +

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

What risk level is discover? +

discover is a Read tool with low risk. Read-only tools are generally safe to allow by default.

Can I rate-limit discover? +

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

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

discover is provided by the Shellgate MCP server (matthiastjong/shellgate). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Shellgate tool call.

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

CHECK YOUR STACK →