list_index_patterns

THE RISK

Low Risk

Why list_index_patterns needs a policy

This tool retrieves and lists existing index pattern configurations from OpenSearch Dashboards. It is a read-only operation with no data modification, deletion, or code execution capabilities. The blast radius of misuse is minimal—an attacker gains visibility into index structure but cannot alter data, delete indices, or trigger external operations. Severity is low because the exposure is informational metadata only.

From the tool's definition Tool name 'list_index_patterns' and description 'List OpenSearch Dashboards index patterns' indicate a query/retrieval operation that reads metadata about index patterns without modification or side effects.

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

POLICY

How to control list_index_patterns

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

policy.json

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

list_index_patterns 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 OpenSearch MCP Server — 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 OpenSearch MCP Server tools

Execute search_documents Search documents in an opensearch index with a custom query Read get_cluster_health Get cluster health status Read get_cluster_stats Get cluster statistics Read get_hot_threads Check hot threads on nodes Read get_index_templates Get index template configurations Read get_ism_policies Get ISM policies and their configurations Read get_mapping Get index mapping Read get_recovery_status Get recovery status and estimated completion time

All 14 OpenSearch MCP Server 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 list_index_patterns

What does the list_index_patterns tool do? +

List OpenSearch Dashboards index patterns2. It is categorised as a Read tool in the OpenSearch MCP Server MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on list_index_patterns? +

Register the OpenSearch MCP Server MCP server in PolicyLayer and add a rule for list_index_patterns: 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 OpenSearch MCP Server. Nothing to install.

What risk level is list_index_patterns? +

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

Can I rate-limit list_index_patterns? +

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

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

list_index_patterns is provided by the OpenSearch MCP Server MCP server (seohyunjun/opensearch-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 OpenSearch MCP Server tool call.

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

CHECK YOUR STACK →