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Mocking & Dry-Run Development EnvironmentZero-Risk Test Environment

Test autonomous email agents in a realistic dry-run sandbox with zero delivery risk

Develop and benchmark AI agent tool calling, prompt templates, and autonomous loops without spamming real inboxes or burning production quota. Inspect rendered HTML, headers, and logs in real time.

3,000 emails/month freeZero credit card requiredSub-20ms edge latency
Nothing sent
Sandbox Dispatch Latency
Dry-run; no provider is called
Unlimited
Test Sends Quota
Zero quota deduction
100%
Iframe Sandbox Isolation
Strict security boundaries
Developer Ergonomics

Drop into your application in under 60 seconds

Native typed interfaces with zero unnecessary dependencies. Built for standard fetch and modern edge runtimes.

$npm install sadasend
sandbox-test.ts
typescript
TYPESCRIPT
import { SadaSend } from 'sadasend';

// Initialize with sandbox mode test key (prefixed with "sada_test_")
const sandbox = new SadaSend(process.env.SADASEND_TEST_KEY!);

export async function runAgentBenchmarkSuite() {
  const result = await sandbox.emails.send({
    from: 'test-agent@sandbox.sadasend.com',
    to: 'customer-simulation@example.com',
    subject: 'Test Agent Tool Invocation',
    html: '<p>Evaluating agent response formatting & token usage.</p>',
    tags: ['benchmark', 'eval-suite']
  });

  // Returns mock delivery status with inspection URL
  console.log('Sandbox simulation verified:', result.id);
  console.log('Inspect rendered email:', `https://app.sadasend.com/logs/${result.id}`);
}
Core Infrastructure

Engineered for high deliverability and zero incident risk

Every layer from edge connection pooling to per-key rate limits is designed to keep critical transactional dispatches fast, reliable, and contained.

Zero Real-World Delivery

Emails sent with test keys (sada_test_*) are captured safely in the dashboard without ever transmitting over SMTP to external mail servers.

HTML & CSS Sandboxed Inspector

Inspect full rendered email templates inside an isolated sandbox iframe, previewing responsiveness across mobile and desktop clients.

Simulate Bounces & Delivery Failures

Pass test email addresses (e.g. bounce@simulator.sadasend.com) to test your application webhook handling and dead-letter queue retries.

CI/CD & Eval Suite Integration

Integrate sandbox dispatches into GitHub Actions and pytest suites to validate agentic tool calling on every pull request.

Architectural Comparison

SadaSend vs Testing on Production Inboxes

Testing autonomous agents with live email credentials risks accidental email blasts, spam complaints, and domain reputation damage. SadaSend sandbox is 100% safe.

Feature & CapabilitySadaSendTesting on Production Inboxes
Dedicated Test Mode API Keys
Web Dashboard HTML Previewer
Simulated Bounce & Complaint Triggers
Zero Production Quota Consumption
Forever Free Tier
Transparent Economics

Start with 3,000 emails every month at zero cost

No artificial paywalls on security. Unlike legacy providers that reserve recipient allowlists or dedicated IP pools for high enterprise tiers, every SadaSend account receives full safety controls from day one.

3,000 dispatches monthly forever with zero credit card
All safety gates, allowlists, and velocity limits included
Scale seamlessly: Starter ($12/mo for 10k), Pro ($19/mo for 50k), Scale ($79/mo for 250k)
Free Developer Plan
$0 / mo

No credit card required

Create Free AccountCompare all paid plan tiers
Frequently Asked Questions

Everything you need to know about AI agent email sandbox

Clear, transparent answers on deliverability, API authentication, and rate limits.

No. Dispatches executed with test keys (prefixed with sada_test_) are completely free and do not deduct from your monthly quota.
Technical Deep Dives

Related developer guides and architectural tutorials

Explore step-by-step production implementation blueprints, benchmarks, and protocols.

Documentation

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Connect AI agents directly to SadaSend via Model Context Protocol (MCP). Inspect tools, configure execution scopes, and enable human approval holds.

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Documentation

AI coding agent rules (AGENTS.md, Cursor, Claude)

Setup instructions and rule files for AI coding agents: AGENTS.md, .cursorrules, CLAUDE.md, and hosted MCP configuration.

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Documentation

Official Client SDKs (TypeScript & Python)

Official zero-dependency client SDKs for SadaSend. TypeScript and Python packages are live on npm and PyPI with typed results and auto-idempotency.

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