search_files

THE RISK

Low Risk

Why search_files needs a policy

This tool searches the filesystem for matching files/directories using pattern matching. It retrieves information about files without modifying, deleting, or executing anything. The 'search' operation is a canonical example of a Read category tool—it gathers data to inform decision-making but produces no irreversible changes or code execution.

From the tool's definition Tool name 'search_files' and description 'Recursively search for files and directories matching a pattern' indicate a query operation with no data modification or side effects.

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

POLICY

How to control search_files

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

policy.json

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

search_files 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 Filesystem MCP Server SSE — 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 Filesystem MCP Server SSE tools

Write create_directory Create a new directory or ensure a directory exists. Can create multiple Write edit_file Make line-based edits to a text file. Each edit replaces exact line sequences Write move_file Move or rename files and directories. Can move files between directories Write write_file Create a new file or completely overwrite an existing file with new content. Read directory_tree Get a recursive tree view of files and directories as a JSON structure. Read get_file_info Retrieve detailed metadata about a file or directory. Returns comprehensive Read list_allowed_directories Returns the list of directories that this server is allowed to access. Read list_directory Get a detailed listing of all files and directories in a specified path.

All 11 Filesystem MCP Server SSE 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 search_files

What does the search_files tool do? +

Recursively search for files and directories matching a pattern. It is categorised as a Read tool in the Filesystem MCP Server SSE MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on search_files? +

Register the Filesystem MCP Server SSE MCP server in PolicyLayer and add a rule for search_files: 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 Filesystem MCP Server SSE. Nothing to install.

What risk level is search_files? +

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

Can I rate-limit search_files? +

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

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

search_files is provided by the Filesystem MCP Server SSE MCP server (ysthink/filesystem-mcp-server-sse). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Filesystem MCP Server SSE tool call.

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

CHECK YOUR STACK →