Use when a user needs advice or implementation help for sending one or many emails through Sendmux: choose the HTTP Sending API versus SMTP, design single or batch sends, attach files, apply idempotency, or inspect send results through MCP, CLI, SDK, or direct HTTP.
Install
npx skills add Sendmux/skills --skill sendmux-send-emailnpx skills add Sendmux/skills --skill sendmux-send-email -a claude-code -gnpx skills add Sendmux/skills --skill sendmux-send-email -a codex -ggemini skills install https://github.com/Sendmux/skills.git --path skills/sendmux-send-emailgh skill install Sendmux/skills sendmux-send-emailgit clone --depth 1 https://github.com/Sendmux/skills /tmp/Sendmux__skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/Sendmux__skills/skills/sendmux-send-email ~/.claude/skills/sendmux-send-email # Claude Code
cp -R /tmp/Sendmux__skills/skills/sendmux-send-email ~/.agents/skills/sendmux-send-email # Codex, Cursor, Gemini CLI, Copilot, OpenCode