Lucairn MCP Server runs on your own machine — the client starts it, so there is no endpoint to ping. 84 installs a week from npm. Last commit 11 Oct 2026.
Pseudonymizes PII before your LLM and returns a cryptographically signed receipt per response.
What the code does
We read the source, 2 d 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.
if err := os.MkdirAll(filepath.Join(out, d), 0o755); err != nil {
…RATED","data_seen":["customer_id"],"data_not_seen":["context","prompt_template","inference_result"],"canonical_payload":"eyJjbGFpbV9pZCI6ImNsbV8wMTllYWVkNS1lZmY1LTc5NzUtOGNiMS0xMjc1YTNhODA5ZDkiLCJjbGFpbV90eXBlIjoiVE9LRU5fR0VORVJBVEVEIiwiZGF0YV9ub3Rfc2VlbiI6WyJjb250ZXh0IiwicHJvbXB…
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 lucairn-mcp-server -e 'LUCAIRN_API_KEY=<LUCAIRN_API_KEY>' -- npx -y @lucairn/mcp-server{
"mcpServers": {
"lucairn-mcp-server": {
"command": "npx",
"args": [
"-y",
"@lucairn/mcp-server"
],
"env": {
"LUCAIRN_API_KEY": "<LUCAIRN_API_KEY>"
}
}
}
}[mcp_servers.lucairn-mcp-server]
command = "npx"
args = ["-y", "@lucairn/mcp-server"]
env = { LUCAIRN_API_KEY = "<LUCAIRN_API_KEY>" }{
"mcpServers": {
"lucairn-mcp-server": {
"command": "npx",
"args": [
"-y",
"@lucairn/mcp-server"
],
"env": {
"LUCAIRN_API_KEY": "<LUCAIRN_API_KEY>"
}
}
}
}{
"servers": {
"lucairn-mcp-server": {
"type": "stdio",
"command": "npx",
"args": [
"-y",
"@lucairn/mcp-server"
],
"env": {
"LUCAIRN_API_KEY": "<LUCAIRN_API_KEY>"
}
}
}
}Put your own value in place of
<LUCAIRN_API_KEY> (Lucairn gateway API key (lcr_live_*). Issued at https://lucairn.eu/account/keys. Free tier requires BYOK upstream LLM keys (ANTHROPIC_API_KEY or OPENAI_API_KEY)).
The author’s registry entry marks it as required.
Optional settings from the registry entry, left out of the block above:
ANTHROPIC_API_KEY (Upstream Anthropic API key. Used when the requested model is claude-* / anthropic-*. Required if you call Claude models on the free tier (BYOK)), OPENAI_API_KEY (Upstream OpenAI API key. Used when the requested model routes to OpenAI. Required if you call OpenAI models on the free tier (BYOK)), LUCAIRN_BASE_URL (Override the gateway URL. Defaults to https://gateway.lucairn.eu (production). Set this to point at a self-hosted Lucairn deployment), LUCAIRN_TRANSPORT (Transport mode for the MCP server. One of 'direct-http' (default; v1.1+ behavior) or 'stdio-bridge' (v1.2+ opt-in)).
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Lucairn MCP Server — questions
Answers built from our own checks of this server.