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Twilio Verify API: CORS for browser clients, SMS OTP delivery, and why secrets stay on the server
Never call Twilio REST from browsers with account credentials; proxy verification through your API with proper CORS and rate limits.
1 min read
twiliosmscors
Regulatory compliance
SMS templates may need pre-approval per country—misconfigured messages fail before CORS even matters.
10DLC registration in the US affects throughput and error codes your SPA should map to UX copy.
Fallback channels
WhatsApp or voice fallbacks change user consent flows—update CORS and redirect URIs when adding channels.
Log channel-specific failures separately from HTTP-layer CORS denials.