mcp-langfuse@0.2.0
VERIFIEDPublisher claims: "Model Context Protocol server for Langfuse, built for v4 events-only deployments" Observed in sandbox: no network, touches nothing outside the project, writes no memory.
Coverage
Server started and answered tools/list.- Tested
- MCP initialize and tools/list · every tool description, for hidden instructions · every file read, file written and host contacted by what ran
- Not tested
- what the tools do when called with real credentials
Before you give it your token
- It will ask for
LANGFUSE_SECRET_KEYConfiguration, not credentials: LANGFUSE_ALLOW_WRITES, LANGFUSE_BASE_URL, LANGFUSE_DEBUG, LANGFUSE_HOST, LANGFUSE_KEYS_FILE, LANGFUSE_MAX_RETRIES, LANGFUSE_PROJECT, LANGFUSE_PROJECTS, LANGFUSE_PUBLIC_KEY- Where it talks to
- no vendor host named in the codeAlso langfuse.com — not the publisher's domain; check what for before connecting.
- What the honeypot saw
- no credential files read · no network
- What we could not test
- what the tools do when called with real credentials
Connect it with a scoped credential, under the guard, and read the third-party hosts first. The code names langfuse.com as well as its own vendor. The guard injects LANGFUSE_SECRET_KEY only into requests to the host you bind (and its subdomains) and refuses the rest.
Never paste a credential into a chat, a ticket or a report, including ours. How the guard holds it.
Is [email protected] safe to install?
KillerSkills ran it in the KillerSkills honeypot sandbox (2 scenarios) on 2026-11-12 and scored it 85/100 (Verified). It did what it claims and nothing else we could detect: no undeclared network egress, no credential reads, no persistent instruction writes. Summary: no network, touches nothing outside the project, writes no memory.
Behavior trace
Honeypot run · 32 s · 2 scenariosStatic findings
if (process.platform !== "win32" && statSync(path).mode & 63) problems.push(`${path} holds secret keys and is readable by other users. Run: chmod 600 ${path}`);Fix: Request the narrowest permission that works; replace wildcards with the exact paths or hosts.No other findings across 2,149 lines in 9 files.
Cost to the agent
Tokens estimated at four characters each. The tool list is re-read by the agent on every turn, so it is the number to compare between servers that do the same job: ranked across the index.
Known vulnerabilities
No advisories in OSV for @mgcrea/mcp-langfuse@0.2.0 as of 2d ago. This is the package itself, not its dependencies.