https://otterblocx.com/blog Engineering deep dives, channel benchmarks, and production patterns from the team building the Blocx programmable messaging operator console. en-us Tue, 12 May 2026 00:00:00 GMT https://otterblocx.com/blog/webhooks-rest-vs-smtp-for-auth-email https://otterblocx.com/blog/webhooks-rest-vs-smtp-for-auth-email Tue, 12 May 2026 00:00:00 GMT Why REST + webhooks beats raw SMTP for auth and product email — retries, observability, templating, and replies — and the narrow cases where SMTP still wins. https://otterblocx.com/blog/ai-agent-that-texts https://otterblocx.com/blog/ai-agent-that-texts Mon, 11 May 2026 00:00:00 GMT An LLM-driven SMS agent end-to-end: tool definition, send through Blocx, webhook receiver for replies — in roughly 100 lines of Node. https://otterblocx.com/blog/cold-start-email-sender-reputation https://otterblocx.com/blog/cold-start-email-sender-reputation Fri, 08 May 2026 00:00:00 GMT A practical 30-day SPF/DKIM/DMARC plus volume-curve plan to warm a brand-new sending domain — provider-agnostic. https://otterblocx.com/blog/carrier-passthrough-fees-explained https://otterblocx.com/blog/carrier-passthrough-fees-explained Wed, 06 May 2026 00:00:00 GMT An A2P 10DLC primer: what US carrier passthrough fees actually pay for, and a worked all-in cost example.