FailTrace runs on your own machine — the client starts it, so there is no endpoint to ping. 1 658 installs a week from npm. Last commit 7 Sep 2026.
Debugging experiments for coding agents: reproduce failures and verify fixes with test evidence.
What the code does
We read the source, 17 h ago · rules 3dff92dd89df
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.
killer = spawn(executable, ['/pid', String(pid), '/T', '/F'], {
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 failtrace -- npx -y failtrace{
"mcpServers": {
"failtrace": {
"args": [
"-y",
"failtrace"
],
"command": "npx"
}
}
}[mcp_servers.failtrace]
command = "npx"
args = ["-y", "failtrace"]{
"mcpServers": {
"failtrace": {
"args": [
"-y",
"failtrace"
],
"command": "npx"
}
}
}{
"mcpServers": {
"failtrace": {
"args": [
"-y",
"failtrace"
],
"command": "npx"
}
}
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FailTrace — questions
Answers built from our own checks of this server.