This style skill is not clearly malicious, but its installer persistently changes local agent configurations and hook/plugin behavior beyond what a terse-answer skill summary suggests.
Install only if you want a persistent multi-agent integration, not just shorter answers. Prefer using the plain SKILL.md manually if that is enough. If you run the CLI, review selected agents and expect writes under Claude/Codex/Cursor/Windsurf configuration paths, possible GitHub fetches, copied hook scripts, and plugin/settings changes. Know how to run fasterizy stop, uninstall hooks/plugins, and inspect backups before relying on it.