FEATURES
Built for the AI-Native Stack
Everything you need to add human oversight to your AI agents. MCP-native, multi-channel, enterprise-ready.
MCP Native
RelayRail speaks the Model Context Protocol fluently. No SDKs, no libraries, no complex setup. Your agent uses RelayRail tools just like any other MCP tool.
- Works with Claude Desktop, Cursor, Cline out of the box
- One-line installation:
npx @relayrail/server start - 5 tools: request_approval, send_notification, await_response, get_pending_commands, register_agent
Multi-Channel Routing
Intelligently route messages via SMS or Email based on priority, urgency, and user preferences. Critical alerts go to SMS; routine notifications go to email.
SMS
High-priority, time-sensitive. 98% open rate within 3 minutes.
Rich content, attachments, lower urgency. Full HTML support.
Flexible Approval Flows
Three approval types to match any workflow. From simple yes/no decisions to complex multi-choice options and free-form text responses.
Yes/No
Simple binary decisions. "Deploy to production?" → YES or NO
Multiple Choice
Offer options. "Which database?" → PostgreSQL, MySQL, MongoDB
Free-form Text
Open-ended questions. "What should this feature be called?"
Multi-Agent Support
Run multiple agents, each with their own dedicated phone number. When you receive an SMS, you instantly know which agent is asking. Reply to the right thread every time.
- Each agent gets a unique SMS line
- Reply to the same number to respond
- Separate API keys for security isolation
True Async Communication
Agents wait patiently for human responses. No polling, no timeouts by default. You respond when you're ready, and the agent picks up right where it left off.
// Agent requests approval
const result = await request_approval({
message: "Ready to deploy?",
type: "yes_no"
});
// Agent waits... you respond via SMS
// Minutes, hours, whenever
if (result.approved) {
// Continue the workflow
}Agent sends request
9:00 AM
Agent waits patiently...
No timeout
You respond: "YES"
2:30 PM (3.5 hours later)
Agent continues workflow
Immediately
Full Visibility Dashboard
Manage agents, view activity logs, track usage, and configure notifications—all from a single dashboard.
Agent Management
Create, rename, activate, and deactivate agents. Rotate API keys with one click.
Activity Logs
See every approval request, notification, and response. Full audit trail for compliance.
Usage Tracking
Monitor SMS and email usage. Stay within quotas and optimize costs.
Enterprise-Grade Security
Built for the demands of modern business. Every layer of the stack is designed with security first.
- API keys hashed with SHA-256
- All traffic encrypted with TLS 1.3
- Row-level security on all database queries
- Complete audit logs for every action
- A2P 10DLC compliance for reliable SMS delivery
Powered by Best-in-Class Services
RelayRail integrates with industry-leading providers for reliable delivery and payment processing.
Telnyx
SMS delivery with global coverage and carrier-grade reliability
Resend
Transactional email with high deliverability and beautiful templates
Stripe
Secure billing and subscription management
Ready to Get Started?
Add human-in-the-loop capabilities to your AI agents in under a minute.