# how.is Domain Trust Check

> how.is Domain Trust Check is a paid API for AI agents from how.is, paid per call via x402, $0.02/call, status unknown (last checked 2026-10-31).

Returns a risk score, verdict (likely_safe/caution/high_risk/inconclusive), and plain-English reasons for a domain based on age, spam/abuse blocklists, and HTTPS certificate validity.

## Facts

- Endpoint: POST https://how.is/v1/domain/trust?utm_source=zero.xyz
- Price: $0.02/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-31
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/how-is-domain-trust-check-13e11216
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_5Hp-qR2LtB1qG2C3-nqlo

Status and success rate cover calls made through Zero and Zero's own probes. Third-party monitors may report differently.

## How to call it through Zero

Zero handles the 402 payment challenge and records the run. With the Zero CLI installed (`npm i -g @zeroxyz/cli`):

```sh
zero fetch --capability how-is-domain-trust-check-13e11216 -d '<json body>'
```

Example prompt: Before I click that link, can you check whether crypto-rewards-bonus.io is safe — give me a risk score and tell me if it's on any abuse blocklists or has a dodgy certificate?

## When to prefer this

Use this endpoint when an agent needs a quick, structured safety verdict on a bare domain before fetching, authenticating, or paying — especially when you want a combined signal from domain age, abuse blocklists, and HTTPS validity in a single call rather than querying each source separately.

## Known failure modes

- Invalid or malformed domain name returns a validation error
- Blocklist services unresponsive results in inconclusive verdict with unanswered blocklists listed
- Very new domain with no data may return inconclusive or limited reasons
- Payment failure over x402 prevents the check from running
- Domain with no HTTPS certificate returns https_valid: false

## How this service works

Should an agent click, sign in to, or pay this domain? A risk score and verdict (likely_safe / caution / high_risk, or inconclusive when a check could not run) with plain-English reasons, from domain age, spam/abuse blocklists and the HTTPS certificate.

## Output

A JSON object containing: a verdict string (likely_safe, caution, high_risk, or inconclusive), a numeric risk_score from 0–100, an array of reasons each with a risk level and plain-English explanation, the domain's age in days, a list of blocklist listings found, any blocklists that did not respond, whether the HTTPS certificate is valid, and any checks that could not be run. Also includes a payment receipt with charge and settlement transaction hash.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "domain": {
   "type": "string",
   "maxLength": 253,
   "description": "A bare domain name, e.g. example.com"
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json",
 "example": {
  "data": {
   "_shape": "data: verdict, risk_score (0-100), reasons[{risk, why}], age_days, blocklist_listings, blocklists_unanswered[], https_valid, not_checked[]."
  },
  "result": "Trust check for the requested subject",
  "receipt": {
   "rail": "x402",
   "tool": "trust",
   "charge_usd": 0.02,
   "settlement_tx": "0x…"
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/how-is-domain-trust-check-13e11216/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from how.is](https://www.zero.xyz/host/how.is/llms.txt)