Perf MCP runs on your own machine — the client starts it, so there is no endpoint to ping. 35 installs a week from npm. Last commit 19 Feb 2026.
Fact-check and fix AI outputs. Hallucination detection, schema validation, auto-repair.
Nothing serious here today
Today is the operative word: we check Perf MCP 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 mcp add perf-mcp -e 'PERF_API_KEY=<PERF_API_KEY>' -- npx -y perf-mcp{
"mcpServers": {
"perf-mcp": {
"command": "npx",
"args": [
"-y",
"perf-mcp"
],
"env": {
"PERF_API_KEY": "<PERF_API_KEY>"
}
}
}
}[mcp_servers.perf-mcp]
command = "npx"
args = ["-y", "perf-mcp"]
env = { PERF_API_KEY = "<PERF_API_KEY>" }{
"mcpServers": {
"perf-mcp": {
"command": "npx",
"args": [
"-y",
"perf-mcp"
],
"env": {
"PERF_API_KEY": "<PERF_API_KEY>"
}
}
}
}{
"servers": {
"perf-mcp": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"perf-mcp"
],
"env": {
"PERF_API_KEY": "<PERF_API_KEY>"
}
}
}
}Put your own value in place of
<PERF_API_KEY> (Your Perf API key (get one at dashboard.withperf.pro)).
The author’s registry entry marks it as required.
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Perf MCP — questions
Answers built from our own checks of this server.