put_alias · Elasticsearch/OpenSearch MCP Server MCP

WHAT IT DOES

What put_alias does on Elasticsearch/OpenSearch MCP Server

AI agents use put_alias to create or update resources in Elasticsearch/OpenSearch MCP Server — usually the action step of a workflow, after the agent has gathered context. Every call changes real data in your Elasticsearch/OpenSearch MCP Server environment.

WHY IT NEEDS A POLICY

Why put_alias needs a policy

The put_alias tool creates or updates index aliases, which are reversible metadata operations. This is a Write-category action because it modifies cluster configuration (alias mappings) but does not delete data or execute arbitrary code. Severity is medium because misconfiguration could redirect queries or cause service disruption, but changes can be undone via subsequent alias updates or deletions.

From the tool's definition Tool name 'put_alias' and description 'Create or update an alias' indicate create/modify operations on index aliases without data deletion.

Attacks that exploit this kind of access

Recommended rule Ready

Verdict

put_alias Rate-limited

put_alias stays usable, but capped — an agent stuck in a loop can't make hundreds of changes a minute. Everything else on the server is denied unless you say otherwise.

View as policy code

policy.json

{
  "version": "1",
  "default": "deny",
  "tools": {
    "put_alias": {
      "limits": [
        {
          "counter": "put_alias_rate",
          "window": "minute",
          "max": 30,
          "scope": "grant"
        }
      ]
    }
  }
}

LIMIT THIS TOOL →

Instant setup, no code required.

PolicyLayer is an MCP gateway: every tool call is checked against your rule before it reaches Elasticsearch/OpenSearch MCP Server, so you can run agents against it safely.

FAQ

Questions about put_alias

What does the put_alias tool do? +

Create or update an alias for a specific index. It is categorised as a Write tool in the Elasticsearch/OpenSearch MCP Server MCP Server, which means it can create or modify data. Consider rate limits to prevent runaway writes.

How do I enforce a policy on put_alias? +

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

What risk level is put_alias? +

put_alias is a Write tool with medium risk. Write tools should be rate-limited to prevent accidental bulk modifications.

Can I rate-limit put_alias? +

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

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

put_alias is provided by the Elasticsearch/OpenSearch MCP Server MCP server (rbedoyag/elasticsearch-mcp-server). PolicyLayer sits as a proxy in front of this server to enforce policies before tool calls reach the server.