once MCP Server

by aurumflux20 Your server? Claim it

local only

once runs on your own machine — the client starts it, so there is no endpoint to ping. 92 installs a week from pypi. Last commit 12 Aug 2026.

Run a side effect exactly once under retries, redelivery, and concurrent workers.

Installs per day peak 28 · avg 12 · -4% w/w

a month agotoday

Installs / week

pypi · once-kernel

Stars

0 open issues

12 Aug 2026

Last commit

from GitHub

Apache-2.0

License

Python

Nothing serious here today

Today is the operative word: we check once every 15 minutes and re-read its code on every release. Watch it and you find out the day that stops being true.

Connect this server

This server runs on your own machine — install it with the package manager and the client starts it for you. Package name taken from the official registry entry.

Claude Code Claude Desktop Codex Cursor VS Code

run in your terminal

claude mcp add once-kernel -- uvx once-kernel

~/Library/Application Support/Claude/claude_desktop_config.json

{
  "mcpServers": {
    "once-kernel": {
      "args": [
        "once-kernel"
      ],
      "command": "uvx"
    }
  }
}

~/.codex/config.toml

[mcp_servers.once-kernel]
command = "uvx"
args = ["once-kernel"]

.cursor/mcp.json

{
  "mcpServers": {
    "once-kernel": {
      "args": [
        "once-kernel"
      ],
      "command": "uvx"
    }
  }
}

.vscode/mcp.json

{
  "mcpServers": {
    "once-kernel": {
      "args": [
        "once-kernel"
      ],
      "command": "uvx"
    }
  }
}

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once — questions

Answers built from our own checks of this server.

Why is there no uptime for once?

once runs on your own machine over stdio — there is no network address to reach, so uptime cannot be measured for it by anyone. What can be measured is adoption: the pypi package once-kernel was installed 92 times last week.

How do I connect once?

Copy the ready config from this page — we generate it for Claude Code, Claude Desktop, Codex, Cursor and VS Code, each with the file path that client actually reads. It runs locally, so the command pulls once-kernel straight from pypi; nothing to host, nothing to sign up for.

How many people use once?

The pypi package once-kernel was installed 92 times in the last week. Week over week that is -4%. We show installs rather than GitHub stars on purpose: a star is a bookmark, an install is someone actually running it.

Is once open source?

Yes — it is published under the Apache-2.0 licence, written in Python and 0 stars on GitHub. The source link is on this page, so you can read exactly what it does with your data before you connect it.