SMS API: how it works and what to look for
What an SMS API does, what to check before you pick one, from delivery webhooks to STOP and number types, and a first text sent with curl and Node.
Transactional SMS: rules, examples and templates
What makes a text transactional rather than marketing, the consent each needs, templates with their character and message counts, and how to send one.
10DLC registration: brand, campaign and trust score
10DLC registration explained: the brand and the campaign carriers ask for, how trust scores set your limits, what it costs, and toll-free or short code instead.
Toll free verification: get an SMS number approved
Toll free verification is the check carriers make before a toll-free number may text: what it asks for, how long review takes, why it fails and how to fix it.
Order confirmation email and abandoned cart flows
What an order confirmation email must contain, how to send it exactly once, and how to run abandoned cart emails that only reach subscribers who did not buy.
SMTP relay explained (2026 Full Guide)
What an SMTP relay is, when you need one, and how to set one up: ports 465 and 587, the login, limits, reply codes, and settings for WordPress and Laravel.
Schedule email API: send at a time you choose
Schedule an email with one scheduled_at field, move it with PATCH or cancel it, and see the real responses, the 30-day window and the daylight-saving traps.
Email API rate limits: headers and backoff
Email API rate limits, measured: the ratelimit headers Rasket sends, what a 429 looks like, and Node and Python backoff that retries without sending twice.
Email template variables in an order confirmation
Email template variables worked through one order confirmation: declare them, refuse bad values, render line items and give an agent a send-only MCP tool.
Email API vs SMTP (2026 Full Guide)
Use an email API when you can change the sending code, and SMTP when you can't. A decision table, one email sent both ways, and which ports get blocked.
Idempotent email sends: retry without sending twice
How to make email sends idempotent and stop duplicate emails: choosing an Idempotency-Key, a tested retry loop, keys for agents, and what each repeat returns.
Transactional vs marketing email (2026 Full Guide)
How to tell transactional email from marketing email, the US and UK rules for mixed messages, separate sending subdomains, and how to send each kind.
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