SadaSend is a transactional email API with a Model Context Protocol (MCP) server and per-key agent guardrails, built for developers who let AI agents send email on their behalf.
Give your agent email.
Not your whole account.
Scoped API keys, recipient allowlists, and approval mode. The transactional email platform built for autonomous AI agents and modern engineering teams.
3,000 emails free · no card · every guardrail on every plan
// The ceiling, set once when the key is minted.
// The agent gets the key. It cannot widen any of this.
{
scopes: ['send', 'read'], // what it may do
allowlist: ['@yourteam.com'], // who it may reach
rateLimitMax: 50, // how fast
rateLimitWindow: '1h',
mode: 'approval', // who signs off
}Built on the rails Gmail actually checks
Since November 2025 Google, Yahoo, Microsoft and Apple reject non-compliant bulk mail outright rather than filtering it. SadaSend enforces the requirements in the product, not in a help article.
- SPF · DKIM · DMARC
- Verified before your first send is accepted
- RFC 8058
- One-click unsubscribe headers injected automatically
- Complaint rate
- Watched per account, throttled before 0.10%
- Suppression
- Automatic and account-wide on every hard bounce
Every other email MCP hands your agent the whole account
Read the competition carefully and they all promise the same thing: native access to the full platform. That is a capability claim with no control story — and it is the reason your engineering lead says no. SadaSend puts a ceiling on every key.
keys.createEnforced at the API before the send reaches the queue — not in a doc, not in a lint rule, and not dependent on the agent behaving.
Under ten lines to a delivered email
Install, set a key, send. The TypeScript SDK is hand-written — typed template variables, a real error class per failure mode, and automatic retry with idempotency so a retried send is never a duplicate.
bun add sadasendimport { SadaSend } from 'sadasend';
const sada = new SadaSend(process.env.SADASEND_API_KEY!);
await sada.emails.send({
from: 'you@yourdomain.com',
to: 'user@example.com',
subject: 'Welcome aboard',
html: '<strong>It works.</strong>',
});Connects with the tools your team already builds with
Whether you dispatch from visual automation platforms, full-stack BaaS databases, internal ops dashboards, or autonomous AI agents, SadaSend connects seamlessly via standard SMTP (port 587), a sub-20ms REST API, or a native Model Context Protocol (MCP) server.
Automate transactional notifications and customer alerts in n8n workflows with zero SMTP socket timeouts or Gmail rate limits.
Bypass the default 2/hour email limit. Connect SadaSend custom SMTP to deliver unthrottled magic links and verification emails.
Fix broken sendmail in production. Configure SadaSend in the PocketBase Admin UI or trigger custom alerts with Go and JS hooks.
Trigger transactional emails and password resets directly from internal admin panels with your own verified, white-label domain.
Plug SadaSend into visual scenarios using the HTTP request module. High throughput, zero account freeze risks, and webhook sync.
Equip visual AI agents with email sending tools while enforcing scoped keys, recipient allowlists, and human approval mode.
Render beautiful, responsive React Email components server-side and dispatch via Server Actions with zero external SMTP dependencies.
First-party hosted Model Context Protocol server. Agents can compose, preview, and send emails with hardware-grade safety ceilings.
A hosted MCP server with a ceiling
Point your agent at SadaSend and it gets the tools it needs — and none of the ones it should never have. No install required.
claude mcp add --transport http sadasend https://mcp.sadasend.com| Tool | Scope | Does |
|---|---|---|
| send_email | send | Send one, honouring key mode and allowlist |
| preview_email | send | Dry run — render and validate, never send |
| get_email_status | read | Delivery state and full event trail |
| search_emails | read | Filtered log search — the debugging workhorse |
| check_domain_setup | domains | Per-record DNS diagnosis, with the fix |
| check_suppression | read | Is this address suppressed, and why |
| render_template | read | Preview a template without sending |
| get_stats | read | Bounce and complaint rates for a window |
| inspect_allowlist | read | Active key recipient allowlist and approval mode |
| get_key_quota | read | Rate limit usage, remaining sends, and reset time |
There is no create_api_key, no delete_domain, and no remove_suppression tool. An agent that can mint its own credentials or un-suppress a complainer has no ceiling. Those operations live in the dashboard, where a human is present.
- “Send the welcome email to the three users who signed up this morning.”
- “Why did our password reset to dana@example.com bounce yesterday?”
- “Check whether our DNS is set up correctly for sending.”
- “Show me every email that bounced this week, grouped by reason.”
Deliverability tools that tell you the fix
We are building these on the same verification engine that onboards sending domains. Free, no account, no rate limit, no email capture — launching soon.
- SPF checkerSoonResolves every include and counts your lookups against the limit of ten.
- DKIM validatorSoonFetches the selector, checks the key length, verifies a signature.
- DMARC checkerSoonParses your policy and tells you what it actually does to failing mail.
- MX lookupSoonResolves the chain and flags misconfigurations.
- Blocklist checkSoonQueries the major blocklists for an IP or domain.
- Inbox placement testSoonSend one message and see where it lands across major providers.
Where we win, and where we do not
We are new. Resend and Postmark have years of sending reputation we cannot buy. Here is the real picture — if deliverability track record is your only criterion, choose Postmark and we will not argue.
| Capability | SadaSend | Resend | Postmark | Loops |
|---|---|---|---|---|
| Transactional email API | Yes | Yes | Yes | Yes |
| MCP server | Yes | Yes | Partial | Yes |
| Per-key recipient allowlist | Yes | No | No | No |
| Agent approval mode | Yes | No | No | No |
| Dry run / preview send | Yes | Partial | No | No |
| Scoped API keys | Yes | Partial | Partial | Partial |
| SMTP relay | Yes | Yes | Yes | No |
| Free deliverability tools | Yes | No | Partial | No |
| Years of sending reputation | No | Yes | Yes | Partial |
| Marketing campaign suite | No | Yes | No | Yes |
| Visual email designer | No | Yes | No | Yes |
The ceiling is not a paid feature
Every guardrail and all ten MCP tools are on every plan, including the free one. Selling the safety only to people who can already afford it would mean nobody ever finds out why it matters.
- 3,000 emails — one time, not monthly
- 100 emails a day
- 1 sending domain
- 30-day log retention
- All ten MCP tools
- Every guardrail
- 10,000 emails / month
- No daily limit
- 5 sending domains
- 30-day log retention
- SMTP relay
- Free migration
- 50,000 emails / month
- 25 sending domains
- 30-day log retention
- 10 webhook endpoints
- Webhook replay
- Per-attempt delivery logs
- 250,000 emails / month
- Unlimited sending domains
- 90-day log retention
- 25 webhook endpoints
- Priority sending queue
- Response time commitment
Plans are not open for sign-up yet — these tiers are the pricing we will launch with, published early so you can plan against them. Yearly billing saves 15% on Starter and Pro, 20% on Scale. Overage is $0.60, $0.50 or $0.40 per thousand by plan, charged only on what you send above it. No per-seat pricing, ever — that is a model for sales tools, not developer infrastructure.
Get early access to SadaSend
The API, the MCP server and every guardrail are built and tested. What is not open yet is sign-up. Leave your email and you will hear from us once when it is — not a newsletter, and not before there is something to use.
Straight answers
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