most_recent_not_vulnerableLABSCO SUMMARY
The agent checks before it pins, without being asked.
The three tools are shaped for the moment a dependency gets added rather than for an audit run afterwards: ask for the latest safe version and you get one, ask about a pinned version and you get a definitive answer with CVSS attached. Nothing to install and no key, so the cost of leaving it switched on is close to nothing.
What it is
A remote MCP server over PyPI and OSV data. It answers three questions about Python dependencies — is this version vulnerable, what is the newest clean release, and which versions of this specifier are affected — with vulnerability ids, CVSS scores and severity attached.
What you get
- The most recent release of a package with no known vulnerabilities, from a package name alone —
most_recent_not_vulnerable - A verdict on an exact pinned version with vulnerability ids, summaries, CVSS scores, severity ratings and reference URLs —
is_vulnerable - Versions available for a package or specifier with their vulnerabilities, filtered by
cvss_threshold, limited bycount, reduced tomax_observed_scoreper version, and optionally keeping clean versions withretain_passing—lookup
Requirements
No local install and no key: this is a hosted HTTP endpoint. Register https://mcp.fetter.io/mcp with your client — claude mcp add --transport http fetter https://mcp.fetter.io/mcp for Claude Code, codex mcp add fetter --url https://mcp.fetter.io/mcp for Codex, or the same URL over HTTP transport anywhere else.
Setup effort
One command — claude mcp add --transport http fetter https://mcp.fetter.io/mcp
USE CASES
01
Adding a package safely
Ask for the newest release with no known vulnerabilities and pin that, instead of taking whatever is latest.
02
Validating a pin already in the file
Check an exact version and read the ids, summaries and CVSS scores behind the verdict.
03
Auditing a version range
Look up a specifier and see which versions inside it are affected and which are clean.
3 tools
Listed in project docs. Your client may show a different list.
is_vulnerablelookupBEFORE YOU INSTALL
What to know first
Tools you get
3 tools named in the project's documentation.
INSTALLATION
Connect your client
Server setup
Setup
Claude Code:
TERMINAL
claude mcp add --transport http fetter https://mcp.fetter.io/mcpCodex:
TERMINAL
codex mcp add fetter --url https://mcp.fetter.io/mcpAny other client: register the remote URL https://mcp.fetter.io/mcp using the HTTP transport
Hosted endpoint
ENDPOINT URL
https://mcp.fetter.io/mcpAdd this hosted endpoint to your MCP client.
