twilio-sms-send-message

SMS and MMS deep-dive reference. Covers SMS-specific error codes, message filtering troubleshooting ("Messages Being Filtered or Blocked?" diagnostic checklist), MMS media support (US/CA/AU only), and SMS pumping indicators. For sending SMS, use twilio-send-message instead. Use this skill only when debugging SMS delivery issues or needing SMS-specific details not in the consolidated send skill.