SSL Checker API

Check SSL/TLS certificate validity, expiry, issuer, chain details, and security grade for any domain. 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.):

config.json

{
  "mcpServers": {
    "ssl-checker": {
      "url": "https://ssl-checker.api.klymax402.com/mcp"
    }
  }
}

Quickstart -- HTTP (x402)

Terminal

curl -X POST "https://ssl-checker.api.klymax402.com/api/check" \
  -H "Content-Type: application/json" \
  -d '{"domain":"..."}'
# -> 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
`security_check_ssl`	POST	`/api/check`	$0.005	Check SSL certificate for a domain

`security_check_ssl`

Use this when you need to check if a domain's SSL/TLS certificate is valid, when it expires, and who issued it. Returns structured certificate data in JSON.

Parameters

Name	Type	Required	Description
`domain`	string	yes	Domain name to check SSL certificate (e.g. example.com)

Example response:

config.json

{"domain":"example.com","valid":true,"expiryDate":"2026-12-15","daysRemaining":245,"issuer":{"name":"DigiCert","organization":"DigiCert Inc"},"protocol":"TLSv1.3","securityGrade":"A+"}

When to use: deploying a website, FOR monitoring certificate expiration, auditing security posture, and validating HTTPS setup.

Not for: DNS lookup (use network_lookup_dns), HTTP headers analysis (use network_analyze_headers), port scanning (use network_scan_ports).

Example agent prompts

"Check if a domain's SSL/TLS certificate is valid, when it expires, and who issued it"

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