Is mcp-builder safe to install?

No critical findings, some security notes. The scan covers prompt injection, hidden Unicode, remote code execution and credential access in every text file of the skill. It cannot judge intent, so read any flagged line in context before installing.

How was this score calculated?

Four checks of 25 points each: spec, efficiency, clarity and security. Findings take points off the check they belong to, and any critical finding caps the grade at F. The same scanner runs in your browser at proskills.dev/scan.

Is this report current?

It was made from commit dbd4588 on 2026-10-16. If the skill has changed since, paste the new version into the scanner for a fresh score.

I wrote this skill. Can I fix the score or have the page removed?

Fix the findings and push. The reports are rebuilt from GitHub on a schedule, so the next run picks the change up. To have the page removed, open an issue on the ProSkills GitHub repo.

Scan reports · anthropics/skills

mcp-builder: scan report

Guide for creating high-quality MCP (Model Context Protocol) servers that enable LLMs to interact with external services through well-designed tools. Use when building MCP servers to integrate external APIs or… An automated scan of this public skill from anthropics/skills: security, token cost, spec and clarity, with every finding and its fix.

Result

Verdict

mcp-builder

88/100 · grade B

anthropics/skills/skills/mcp-builder at dbd4588

Spec 25 · Efficiency 25 · Clarity 20 · Security 18 (each out of 25)

Always loaded 73 tokens · on trigger 2,178 · on demand 28,144

sec/undocumented-script warn · SKILL.mdBundles scripts that SKILL.md never explains. Say what each script does and when it runs.
clarity/vague info · SKILL.md8 vague phrases (high-quality, best practices, as needed). Replace with concrete thresholds.
sec/plain-http info · SKILL.mdLinks over plain http.

Where it comes from

Source

Fact	Value
Repository	anthropics/skills
Skill folder	skills/mcp-builder
Stars	181,568
License	None stated
Commit scanned	dbd4588
Scanned	2026-10-16
Files	10

ProSkills doesn't host or redistribute this skill. Get it from its repository, and check the license before reusing it. Something wrong here? Open an issue for a rescan or removal.

For maintainers

Badge for the README

If you maintain this skill, this badge shows its score and links to this report. Fix findings and the score moves with the next scan.

[![ProSkills scan 88/100](https://proskills.dev/badge?score=88)](https://proskills.dev/reports/anthropics-mcp-builder)

Alternatives

Scanned alternatives on ProSkills

Skills in the ProSkills catalog that cover similar ground. Every one passes the same scanner before it ships.

MCP BuilderA small, safe MCP server for your internal API.Loads when the user builds or fixes an MCP server.5 rules · Agent OpsScan 100$12

Same repository

More from anthropics/skills

FAQ

Questions

Is mcp-builder safe to install?: No critical findings, some security notes. The scan covers prompt injection, hidden Unicode, remote code execution and credential access in every text file of the skill. It cannot judge intent, so read any flagged line in context before installing.
How was this score calculated?: Four checks of 25 points each: spec, efficiency, clarity and security. Findings take points off the check they belong to, and any critical finding caps the grade at F. The same scanner runs in your browser at proskills.dev/scan.
Is this report current?: It was made from commit dbd4588 on 2026-10-16. If the skill has changed since, paste the new version into the scanner for a fresh score.
I wrote this skill. Can I fix the score or have the page removed?: Fix the findings and push. The reports are rebuilt from GitHub on a schedule, so the next run picks the change up. To have the page removed, open an issue on the ProSkills GitHub repo.

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