Custom Elasticsearch MCP Server

Custom Elasticsearch MCP Server

A simple MCP (Model Context Protocol) server for Elasticsearch designed for cloud environments where your public key is already authorized on the server.

Why This Custom Version?

No API Key Required - Unlike the official Elasticsearch MCP server that requires both ES_URL and ES_API_KEY, this version only needs the URL since your public key is already trusted on the cloud server.

Enhanced Tools - Better usability with optional parameters and improved defaults compared to the official version.

What This Does

This MCP server connects Cursor to your Elasticsearch cluster with 4 powerful tools:

• list_indices - List all indices (optional pattern filter)
• search - Full Elasticsearch Query DSL support
• get_mappings - Get field mappings for any index
• get_shards - View cluster shard information

Quick Start

Build from Source

git clone https://github.com/M0-AR/Custom-Elasticsearch-MCP-Server.git
cd Custom-Elasticsearch-MCP-Server
docker build -t elasticsearch-mcp:latest .

2. Add to Cursor MCP Configuration

Add this to your .cursor/mcp.json file:

Configuration:

{
    "mcpServers": {
        "elasticsearch-custom": {
            "command": "docker",
            "args": [
                "run",
                "-i",
                "--rm",
                "--add-host=host.docker.internal:host-gateway",
                "-e",
                "ES_URL=http://host.docker.internal:9400",
                "elasticsearch-mcp:latest"
            ]
        }
    }
}

3. Restart Cursor

Close and reopen Cursor. You should see the elasticsearch-custom server with 4 tools enabled.

Configuration

Environment Variables:

• ES_URL - Your Elasticsearch URL (default: http://localhost:9400)
• MAX_CONNECTIONS - Maximum concurrent connections (default: 100)
• MAX_KEEPALIVE_CONNECTIONS - Maximum keepalive connections (default: 20)
• CONNECTION_TIMEOUT - Connection timeout in seconds (default: 30)
• REQUEST_TIMEOUT - Request timeout in seconds (default: 30)

For different Elasticsearch ports:

"ES_URL=http://host.docker.internal:9200"

For high-traffic environments:

"MAX_CONNECTIONS=200",
"MAX_KEEPALIVE_CONNECTIONS=50",
"CONNECTION_TIMEOUT=60",
"REQUEST_TIMEOUT=60"

Example Usage

Once connected in Cursor, you can:

• List all indices: "Show me all elasticsearch indices"
• Search data: "Search for sales data in hq.sales index"
• Get mappings: "What fields are in the hq.menuitems index?"
• Check cluster: "Show me the elasticsearch cluster status"

Comparison with Official Server

Concurrent Request Handling

This MCP server is designed to handle multiple parallel requests from multiple applications simultaneously using industry best practices:

**Key Features:**

✅ Async/Await Architecture - Non-blocking I/O for parallel request processing ✅ Connection Pooling - Reuses HTTP connections (up to 100 concurrent) ✅ HTTP/2 Support - Multiplexes multiple requests over single connection ✅ Configurable Limits - Adjust connection limits for your workload ✅ Thread-Safe - FastMCP handles concurrent tool execution safely

**Performance Characteristics:**

• Default: 100 concurrent connections, 20 keepalive connections
• Scalable: Configure up to 1000+ concurrent connections
• Efficient: Connection reuse reduces latency by ~50%
• Reliable: Proper timeout handling prevents connection exhaustion

**Configuration for High Traffic:**

{
    "mcpServers": {
        "elasticsearch-custom": {
            "command": "docker",
            "args": [
                "run", "-i", "--rm",
                "--add-host=host.docker.internal:host-gateway",
                "-e", "ES_URL=http://host.docker.internal:9400",
                "-e", "MAX_CONNECTIONS=200",
                "-e", "MAX_KEEPALIVE_CONNECTIONS=50",
                "-e", "CONNECTION_TIMEOUT=60",
                "-e", "REQUEST_TIMEOUT=60",
                "elasticsearch-mcp:latest"
            ]
        }
    }
}

**Testing Concurrent Requests:**

# Test 10 parallel requests
for i in {1..10}; do