Execute a phased DMARC rollout by inventorying sending sources, configuring SPF/DKIM alignment, and progressing DNS policy from p=none monitoring through p=quarantine to p=reject enforcement, ensuring all legitimate email sources authenticate before unauthorized senders are blocked.
Install
npx skills add mukul975/Anthropic-Cybersecurity-Skills --skill performing-dmarc-policy-enforcement-rolloutnpx skills add mukul975/Anthropic-Cybersecurity-Skills --skill performing-dmarc-policy-enforcement-rollout -a claude-code -gnpx skills add mukul975/Anthropic-Cybersecurity-Skills --skill performing-dmarc-policy-enforcement-rollout -a codex -ggemini skills install https://github.com/mukul975/Anthropic-Cybersecurity-Skills.git --path skills/performing-dmarc-policy-enforcement-rolloutgh skill install mukul975/Anthropic-Cybersecurity-Skills performing-dmarc-policy-enforcement-rolloutgit clone --depth 1 https://github.com/mukul975/Anthropic-Cybersecurity-Skills /tmp/mukul975__Anthropic-Cybersecurity-Skills
mkdir -p ~/.claude/skills ~/.agents/skills
cp -R /tmp/mukul975__Anthropic-Cybersecurity-Skills/skills/performing-dmarc-policy-enforcement-rollout ~/.claude/skills/performing-dmarc-policy-enforcement-rollout # Claude Code
cp -R /tmp/mukul975__Anthropic-Cybersecurity-Skills/skills/performing-dmarc-policy-enforcement-rollout ~/.agents/skills/performing-dmarc-policy-enforcement-rollout # Codex, Cursor, Gemini CLI, Copilot, OpenCode