search_nodes · Elasticsearch Knowledge Graph for MCP

WHAT IT DOES

What search_nodes does on Elasticsearch Knowledge Graph for MCP

AI agents call search_nodes to retrieve information from Elasticsearch Knowledge Graph for MCP without modifying anything — typically the context-gathering step in research, monitoring, and reporting workflows, before the agent takes action elsewhere.

THE RISK

Low Risk

Why search_nodes needs a policy

This tool retrieves or queries data from the knowledge graph without creating, modifying, or deleting any information. It is a read-only operation that returns results based on search criteria. No destructive, financial, or code execution capabilities are implied. The low severity reflects minimal risk if misused by an AI agent, as the worst outcome would be information disclosure of already-stored data.

From the tool's definition Tool name is 'search_nodes' and description states 'Search for nodes in the knowledge graph based on a query'. The verb 'search' indicates a retrieval operation with no modification or side effects.

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

POLICY

How to control search_nodes

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

policy.json

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

search_nodes 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 Elasticsearch Knowledge Graph for MCP — 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 Elasticsearch Knowledge Graph for MCP tools

Destructive delete_entities Delete multiple entities and their associated relations from the knowledge graph Destructive delete_observations Delete specific observations from entities in the knowledge graph Destructive delete_relations Delete multiple relations from the knowledge graph Destructive delete_zone Delete a memory zone and all its entities/relations. Destructive move_entities Move entities between zones (copy + delete from source). Write add_observations Add new observations to existing entities in the knowledge graph Write copy_entities Copy entities between zones with optional relation handling. Write create_entities Create multiple new entities in the knowledge graph

All 23 Elasticsearch Knowledge Graph for MCP 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_nodes

What does the search_nodes tool do? +

Search for nodes in the knowledge graph based on a query. It is categorised as a Read tool in the Elasticsearch Knowledge Graph for MCP MCP Server, which means it retrieves data without modifying state.

How do I enforce a policy on search_nodes? +

Register the Elasticsearch Knowledge Graph for MCP server in PolicyLayer and add a rule for search_nodes: 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 Elasticsearch Knowledge Graph for MCP. Nothing to install.

What risk level is search_nodes? +

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

Can I rate-limit search_nodes? +

Yes. Add a rate_limit block to the search_nodes 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_nodes completely? +

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

search_nodes is provided by the Elasticsearch Knowledge Graph for MCP server (j3k0/mcp-brain-tools). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.

Enforce policy on every Elasticsearch Knowledge Graph for MCP tool call.

Start from Elasticsearch Knowledge Graph for MCP, add the rest of your stack, and see everything your agents can call. Then put policy on all of it.

CHECK YOUR STACK →

Free to start. No card required.

23 Elasticsearch Knowledge Graph for MCP tools catalogued and risk-classified — across an index of 43,000+ MCP servers.