Zerosmtp runs on your own machine — the client starts it, so there is no endpoint to ping. 55 installs a week from npm. Last commit 18 Oct 2026.
A free SMTP relay that still takes a username and password, for devices that cannot do OAuth 2.0.
The author archived this repository on GitHub, meaning it is no longer maintained.
What the code does
We read the source, 23 h ago · rules 995398eba69f
What this server is able to do. For an MCP server this is often the job itself — a terminal server runs commands because that is what it is for. Listed so you know what you are plugging in, not as an accusation.
этот файл ставится пользователю, но в репозитории его нет
return JSON.parse(fs.readFileSync(path.join(KATALOG, nazwa), 'utf8'));
Is this your server and something here is wrong? Tell us — corrections are free and do not require a plan.
This code can reach further than it looks
We found places where it runs commands, builds paths or queries from values it is given. None of that is a flaw by itself — it becomes one when the code changes, and code changes quietly between releases. We re-read it on every one.
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 mcp add zerosmtp -- npx -y zerosmtp-mcp{
"mcpServers": {
"zerosmtp": {
"command": "npx",
"args": [
"-y",
"zerosmtp-mcp"
]
}
}
}[mcp_servers.zerosmtp]
command = "npx"
args = ["-y", "zerosmtp-mcp"]{
"mcpServers": {
"zerosmtp": {
"command": "npx",
"args": [
"-y",
"zerosmtp-mcp"
]
}
}
}{
"servers": {
"zerosmtp": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"zerosmtp-mcp"
]
}
}
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Zerosmtp — questions
Answers built from our own checks of this server.