once
Run a side effect exactly once under retries, redelivery, and concurrent workers.
MCP server · by aurumflux20
About
once is an MCP server published by aurumflux20. Marketplaces we read that list it: 1 (Official MCP Registry). We first saw it on 2026-10-11 and have recorded no change since. As of our marketplace pass on 2026-10-13.
What it asks for
- Runs on your machine
None of the marketplaces we read publishes its tools or the settings it asks for.
What it declares, asks for and runs, in full
Only install plugins from developers you trust. We list what marketplaces publish and do not test plugins.
Package
PyPI once-kernel (once-kernel on PyPI)
- PyPI downloads/week: 44 (2026-10-13)
- PyPI downloads/month: 116 (2026-10-13)
- Latest version on PyPI: 0.2.1, published 2026-08-07
No known vulnerabilities in OSV for 0.2.1 (checked 2026-10-13)
PyPI facts come from pypi.org, PyPI downloads from pypistats.org. Each figure is the registry's own and is never added to another. A registry that publishes no figure shows none: no number is not zero. Vulnerability records come from OSV.dev (CC BY 4.0) and concern the declared version only; a listing that declares no version gets no answer. We do not scan code.
Works with
- Claude Code
- Codex
- Cursor
- VS Code
- Copilot CLI
A one-click link opens the client, which asks you to confirm before it adds the server.
From the marketplaces that list it and the MCP transport it declares, as each client documents them. We do not test plugins.
Connect
Commands and configs built only from what its marketplaces declare. We do not run them for you and do not test plugins.
As a local MCP server: PyPI package
Built from what Official MCP Registry declares.
claude mcp add --transport stdio once-kernel -- uvx once-kernel[mcp_servers.once-kernel]
command = "uvx"
args = ["once-kernel"]{
"mcpServers": {
"once-kernel": {
"command": "uvx",
"args": [
"once-kernel"
]
}
}
}Where it is published
| Marketplace | Status | Version | Figures | Verified | First seen |
|---|---|---|---|---|---|
| Official MCP Registry (Open the registry record) | Listed | 0.2.1 | Downloads/month (PyPI): 116 Downloads/week (PyPI): 44 Forks (GitHub): 0 Stars (GitHub): 0 |
Not marked |
Each figure is the marketplace's own and is never added up across marketplaces. A marketplace that publishes no figure shows none: no number is not zero.
What changed
Nothing has moved on this plugin since we started watching it.
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Found by meaning, not by shared code or a shared repository: similar plugins stay separate products, and this is not a review or a recommendation.
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Data comes from the Official MCP Registry (registry.modelcontextprotocol.io), CC0 1.0. Figures come from our own regular passes over the marketplaces, last read on . We publish no contact details for plugin publishers.