TLS certificate

Inspect the TLS certificate of any public host: subject, issuer, validity window, days remaining, SANs, and SHA-256 fingerprint.

Input

Example output

{
  "host": "example.com",
  "issuer": "DigiCert",
  "validTo": "2027-01-01T00:00:00.000Z",
  "daysRemaining": 204,
  "altNames": [
    "example.com"
  ]
}

Try it - see the 402 challenge (free)

curl -i -X POST https://agent402.tools/api/tls-cert \
  -H "Content-Type: application/json" \
  -d '{"host":"example.com"}'

The response is HTTP 402 Payment Required with exact payment requirements. Any x402 v2 client pays automatically and retries:

Paid call (JavaScript agent)

import { wrapFetchWithPayment } from "@x402/fetch";
import { x402Client } from "@x402/core/client";
import { registerExactEvmScheme } from "@x402/evm/exact/client";
import { privateKeyToAccount } from "viem/accounts";

const client = new x402Client();
registerExactEvmScheme(client, { signer: privateKeyToAccount(KEY) });
const payFetch = wrapFetchWithPayment(fetch, client);

const res = await payFetch("https://agent402.tools/api/tls-cert", {
  method: "POST",
  headers: { "Content-Type": "application/json" },
  body: JSON.stringify({
    "host": "example.com"
  }),
});

Part of these workflows

This tool is one step in 8 curated multi-tool workflows - agents can fetch the whole sequence as an MCP prompt or call https://agent402.tools/api/skill-packs/{slug}/prompt.

• Security audit - Enumerate a domain's external attack surface in one workflow: certs, DNS posture, email auth, HTTP security headers, and tech stack.
• Fraud signals - Is this domain trustworthy, or is it a phishing site / typosquat / scam? Pull the reputation signals an analyst checks before clicking anything: domain age, cert issuance history, hosting reputation, DNS topology, tech-stack fingerprint, and page-content red flags. Different from a security audit - this is about whether the domain is what it claims to be.
• Site status snapshot - The 'is this site healthy, addressable, and crawlable - right now?' workflow. DNS resolution → HTTP reachability → security headers → TLS certificate expiry → robots policy. Five tools, one structured status payload an operator (or an uptime bot, or a pre-flight check before an extract/crawl) can act on.
• Technical SEO audit - Can search engines and AI crawlers actually index this page? One pass over reachability, TLS, robots policy, sitemap health, meta/OpenGraph tags, and the on-page link graph.
• Domain intel - Full domain security and SEO intelligence in one call: WHOIS, DNS, TLS cert, HTTP headers, tech stack, robots policy, and certificate transparency.
• SSL audit - TLS/SSL security posture check: live certificate inspection, HTTP security headers, and CAA DNS records.
• API health check - Is this API endpoint healthy? Liveness check, response headers, and TLS certificate status in one pass.
• Domain age and legitimacy - How old and legit is this domain? WHOIS registration, DNS resolution, and TLS certificate in one pass.

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