Every guardrail on every plan. Including the free one.

Questions people actually ask

Is the free plan really free, or is it a trial?

It is free and it does not expire. You get 6,000 emails a month, every month, and the counter resets on the same day each month — a side project or AI agent can sit on it indefinitely. Every guardrail, all 12 hosted MCP tools, and 100 email verifications are included; nothing is held back for paid plans. The one limit that is not monthly is the shared onboarding domain, which allows 100 messages per account for testing so that one signup cannot spend a sending reputation everybody shares. Verifying your own domain lifts it immediately.

Why can’t I just use a generic email API like SendGrid or Resend with AI agents?

Traditional email APIs assume deterministic human-written code. When an autonomous AI agent loops, hallucinates addresses, or falls for prompt injection, generic APIs blindly dispatch every message, exhausting your credits and permanently damaging your domain reputation. SadaSend enforces hardware-level server guardrails: per-key recipient allowlists, velocity throttles, human-in-the-loop approval holds, and pre-send bounce shields that prompt injections cannot bypass.

Do I still need a separate email verification service like NeverBounce or ZeroBounce?

No. Legacy email APIs force developers to maintain separate subscriptions to services like NeverBounce (often $80 for 10,000 checks) and write complex glue code to verify emails before dispatching. SadaSend integrates an enterprise-grade deliverability engine directly into your sending pipeline: enable verifyBeforeSend: true to intercept disposable burners and invalid mailboxes before dispatch with zero credit penalties, clean batch lists via our in-app Verification Studio (/app/verify), or call verify_email via our hosted MCP server. Extra verification credits cost just $15 per 10,000—more than 80% below standalone cleaners.

What is the Model Context Protocol (MCP) server?

Model Context Protocol (MCP) is the open standard for connecting AI models to external tools and APIs. SadaSend hosts a native, remote MCP server (mcp.sadasend.com) with 12 strictly scoped, non-destructive tools so agents in Claude Desktop, Cursor, and Windsurf can draft, verify, render, and send transactional emails. Destructive operations (such as domain deletion, DNS modification, or minting root API keys) are restricted to authenticated humans in the console.

Why is the free plan a monthly allowance with a daily cap?

Because a shared sending reputation is the one asset an email provider cannot buy back once it is spent. 6,000 emails a month is enough to run real side projects and early-stage production workloads, while the 200-a-day burst limit and warmup ramp ensure new senders build flawless deliverability rather than burning their domain.

What happens when I hit my limit?

On paid plans, sending continues smoothly using your monthly plan allowance and any prepaid top-up credits in your account. You can purchase non-expiring credit packs at any time ($0.79 to $1.20 per thousand emails) to avoid surprise post-paid bills. On the free plan, sending hard-stops at 6,000 emails: nothing is charged, and your logs and domains stay intact.

Do the agent guardrails cost extra?

No, and they never will. Scoped keys, per-key rate limits, recipient allowlists, approval mode, dry run, and the hosted MCP server are on every plan including the free one. Selling safety guardrails only to people who can already afford them would mean nobody ever finds out why they matter.

Can I pay yearly?

Yes. Starter and Pro are 15% cheaper paid yearly, and Scale is 20% cheaper. Resend, Postmark, and Mailgun do not offer annual billing discounts on self-serve plans.

Will you help me move from another provider?

Yes, at no cost on any paid plan. We move templates, sending domains, suppression lists, and webhook endpoints, and verify them against your live traffic before you cut over. This is subject to engineering capacity because we handle each migration directly and would rather pace onboarding than provide slow support.