Help setting up MCP server for OpenSearch Serverless for Claude Desktop

[tyleryy]

Hi, I tried to run the OpenSearch MCP server on my existing OpenSearch Serverless search collection, but ran into a few issues.

Following the instructions, I ran uvx opensearch-mcp-server-py (with the correct environment variables in the terminal session) and got this output, which I believe is correct:

Keeping this standalone MCP server open, I open Claude Desktop as the MCP client with this config:

{
    "mcpServers": {     
    "opensearch-mcp-server": {
      "command": "uvx",
      "args": ["opensearch-mcp-server-py"],
      "env": {
          "OPENSEARCH_URL": "https://***.us-west-2.aoss.amazonaws.com",
          "AWS_REGION": "us-west-2",
          "AWS_ACCESS_KEY_ID": "***",
          "AWS_SECRET_ACCESS_KEY": "***",
          "AWS_SESSION_TOKEN": "***",
          "AWS_OPENSEARCH_SERVERLESS": "true"
      }
  }
}}

And I open Claude and received these error messages:

Here are the logs as well:

2025-07-23T06:56:49.657Z [opensearch-mcp-server] [info] Using MCP server command: uvx with args and path: {
  metadata: {
    args: [ 'opensearch-mcp-server-py', [length]: 1 ],
    paths: [
      '/usr/local/bin',
      '/usr/bin',
      '/usr/bin',
      '/bin',
      '/usr/sbin',
      '/sbin',
      [length]: 6
    ]
  }
} %o
2025-07-23T06:56:49.676Z [opensearch-mcp-server] [error] spawn uvx ENOENT {
  metadata: {
    context: 'connection',
    stack: 'Error: spawn uvx ENOENT\n' +
      '    at ChildProcess._handle.onexit (node:internal/child_process:285:19)\n' +
      '    at onErrorNT (node:internal/child_process:483:16)\n' +
      '    at process.processTicksAndRejections (node:internal/process/task_queues:90:21)'
  }
}

I'm thinking that perhaps the OpenSearch Serverless endpoint is perhaps blocked in some way or is not the correct url? Not too sure. If anyone could help me troubleshoot my issues, that would be great! 😊

EDIT: I just tried using MCP Inspector, and it was able to connect to OpenSearch and run tool calls. So, the issue just seems to be with Claude Desktop (and Cursor, which I also tried).

---

python==3.13
opensearch==2.11.0
Intel i7 Sequoia Mac

[rithin-pullela-aws]

From the logs, it looks like the issue is because the system is unable to find UVX.
Can you make sure you have UV installed in the right path?
I recommend running which uvx to ensure it is installed in the right path.
Try asking LLMs for help ;)

[tyleryy]

I actually was able to get it to run on Claude Desktop and Cursor with this command python -m mcp_server_opensearch instead.

As for the uv issue, I believe I have it installed in the correct path, but Claude is still not able to find it?