Phone Number Validation API

Validate phone numbers worldwide -- carrier, line type, country, E.164 format. Single and batch (50) modes. Pay-per-call via x402 (USDC on Base L2) -- no API key, no signup, no rate-limit wall.

Part of the klymax402 marketplace -- 100 x402 micropayment APIs for AI agents, one wallet, USDC on Base.

Quickstart -- MCP

Add to your MCP client config (Claude Desktop, Cursor, ElizaOS, etc.):

{
  "mcpServers": {
    "phone-validation": {
      "url": "https://phone-validation.api.klymax402.com/mcp"
    }
  }
}

Quickstart -- HTTP (x402)

curl "https://phone-validation.api.klymax402.com/api/validate?phone=..."
# -> 402 Payment Required, with an x402 payment challenge in the response body

Any x402-aware client (@x402/fetch, x402-agent-tools, ATXP) handles the 402 -> sign -> retry cycle automatically.

Tools

Tool	Method	Path	Price	Description
phone_validate_number	GET	/api/validate	$0.008	Validate a phone number and get carrier/type/country info
phone_validate_batch	POST	/api/validate/batch	$0.035	Validate up to 50 phone numbers in a single batch request

phone_validate_number

Use this when you need to validate a phone number and get carrier info. Returns structured validation data in JSON.

Parameters

Name	Type	Required	Description
phone	string	yes	Phone number to validate (e.g. +33612345678, +14155552671, 0033612345678)

Example response:

{"valid":true,"e164":"+33612345678","countryCode":"FR","countryName":"France","carrier":"Orange","lineType":"mobile","localFormat":"06 12 34 56 78","internationalFormat":"+33 6 12 34 56 78"}

When to use: sending SMS or calling a number, FOR CRM data cleaning, lead validation, fraud detection, and KYC phone verification.

Not for: SMS capability check (use sms_validate_number), email validation (use email_verify_address), person data (use person_enrich_from_email).

phone_validate_batch

Use this when you need to validate multiple phone numbers at once (up to 50). Returns an array of validation results in JSON.

Parameters

Name	Type	Required	Description
phones	array	yes	Array of phone numbers to validate (max 50)

Example response:

{"results":[{"phone":"+14155551234","valid":true,"e164":"+14155551234","countryCode":"US","carrier":"T-Mobile","lineType":"mobile"},{"phone":"invalid","valid":false}],"total":2,"validCount":1}

When to use: bulk CRM cleaning, importing contact lists, deduplication pipelines, and batch lead validation.

Not for: single numbers (use phone_validate_number), SMS capability (use sms_validate_number).

Example agent prompts

• "Validate a phone number and get carrier info"
• "Validate multiple phone numbers at once (up to 50)"

Payment

• Protocol: x402 -- HTTP-native pay-per-call, no signup, no API key
• Network: Base L2 (eip155:8453)
• Asset: USDC
• Facilitator: Coinbase CDP (primary), PayAI (fallback)
• Also reachable via ATXP (OAuth-wrapped x402, RFC 9728 protected-resource metadata)

Part of klymax402

100 x402 micropayment APIs for AI agents -- one wallet, USDC on Base, zero signup.

• Catalog: https://klymax402.com/llms.txt
• Full API reference: https://klymax402.com/llms-full.txt
• Live stats: https://klymax402.com/stats

License

MIT