MCP-Bastion runs on your own machine — the client starts it, so there is no endpoint to ping. 437 installs a week from pypi. Last commit 1 Nov 2026.
Security middleware for MCP. Blocks prompt injection, PII leakage, and resource exhaustion.
What the code does
We read the source, 21 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.
return subprocess.run(argv, env=env).returncode
__import__(mod)
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 mcp-bastion -- uvx mcp-bastion-python{
"mcpServers": {
"mcp-bastion": {
"command": "uvx",
"args": [
"mcp-bastion-python"
]
}
}
}[mcp_servers.mcp-bastion]
command = "uvx"
args = ["mcp-bastion-python"]{
"mcpServers": {
"mcp-bastion": {
"command": "uvx",
"args": [
"mcp-bastion-python"
]
}
}
}{
"servers": {
"mcp-bastion": {
"type": "stdio",
"command": "uvx",
"args": [
"mcp-bastion-python"
]
}
}
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MCP-Bastion — questions
Answers built from our own checks of this server.