SMS Validator API
Check whether a phone number can receive SMS and normalize to E.164 while your agent drafts signup or notification flows.
Overview
SMS Validator is a MCP server for the Build phase that checks SMS-capable numbers, mobile vs landline, and E.164 formatting through a remote x402-paid API.
What is this MCP server?
- Remote SSE MCP at sms-validator.api.klymax402.com
- Distinguishes mobile vs landline SMS capability
- E.164 format normalization for international numbers
- x402 micropayment per validation call
- Version 1.1.0; repo sms-validator-x402 on GitHub
- MCP server version 1.1.0
- One documented SSE remote URL in server schema
- x402 micropayment on validation API
What problem does it solve?
Signup and SMS OTP flows break when agents or users paste local formats, landlines, or invalid numbers that only fail after you integrate a provider.
Who is it for?
Builders adding phone login, transactional SMS, or CRM imports who want quick validation inside Claude Code or Cursor.
Skip if: Products that require bulk offline cleansing, strict on-prem data residency without third-party calls, or full fraud scoring beyond SMS reachability.
What do I get? / Deliverables
Your agent can flag non-SMS numbers and propose E.164-normalized values before you wire Twilio, SNS, or similar backends.
- SMS capability assessment (mobile vs landline)
- E.164-normalized phone number candidates for your schemas
Recommended MCP Servers
Journey fit
How it compares
Telephony validation MCP integration, not a full CPaaS SDK or agent skill for copywriting SMS templates.
Common Questions / FAQ
Who is sms-validator for?
Solo developers and small teams implementing SMS-based auth, alerts, or lead capture who want the agent to sanity-check numbers early.
When should I use sms-validator?
Use it while designing signup APIs, OTP flows, or import scripts in Build so numbers are E.164-clean and SMS-eligible before provider integration.
How do I add sms-validator to my agent?
Add the remote MCP server https://sms-validator.api.klymax402.com/mcp (SSE) in your MCP client and configure x402 micropayments for the hosted validator.