# InboxPolicy Send-Decision Email Verification API

> InboxPolicy Send-Decision Email Verification API is a paid API for AI agents from api.inboxpolicy.com, paid per call via x402, $0.01/call, status unknown (last checked 2026-10-12).

Verifies an email address and returns an actionable send decision (send, review, or avoid) with confidence score and deliverability signals

## Facts

- Endpoint: POST https://api.inboxpolicy.com/v1/decide?utm_source=zero.xyz
- Price: $0.01/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-12
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/inboxpolicy-send-decision-email-verification-api-96be538c
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_ZQ0mmmVBpi12DJZJ0NUbo

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 inboxpolicy-send-decision-email-verification-api-96be538c -d '<json body>'
```

Example prompt: Can you check whether john.doe@example.com is safe to email — I need a send or avoid decision with confidence score before we add them to our list?

## When to prefer this

Choose this endpoint when you need an actionable send/avoid decision rather than just a syntactic validity check — it performs live SMTP and domain checks with disposable, catch-all, and role-account signals. Ideal for pre-send list hygiene, signup screening, or CRM enrichment where a binary valid/invalid result is insufficient. The $0.01/call micropayment via x402 requires no account signup, making it suitable for agent workflows that need on-demand verification without API key management. The 72-hour cache keeps repeated checks free.

## Known failure modes

- Invalid or malformed email syntax returns status 'syntax_error' with action 'avoid'
- Temporary DNS or SMTP lookup failures return status 'temporary_unavailable' with action 'retry_later'
- Payment failure via x402 results in a 402 response before verification is attempted
- Rate limiting or network errors return HTTP 4xx/5xx without a verification result
- Unknown domains with catch-all servers may return low-confidence results with action 'review'

## How this service works

Email verification API that returns a decision — send, review, or avoid — with evidence. $0.01/call via x402, no account. Free 72h re-verification.

## Output

Returns a JSON object with an 'action' enum (send, send_with_caution, review, retry_later, or avoid), a confidence score (0–100), a validity status (valid, invalid, unknown, temporary_unavailable, syntax_error), a human-readable reason, boolean signals (disposable, catch_all, free, role_account), a cache flag, and a unique request ID. Billing metadata indicates whether the call was charged.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "email"
 ],
 "properties": {
  "email": {
   "type": "string",
   "description": "Address to evaluate."
  },
  "strictness": {
   "enum": [
    "aggressive",
    "default",
    "strict"
   ],
   "type": "string"
  },
  "force_refresh": {
   "type": "boolean",
   "description": "Bypass the 72h verification cache."
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "object",
 "required": [
  "action",
  "confidence",
  "status"
 ],
 "properties": {
  "cost": {
   "type": "object",
   "properties": {
    "credits": {
     "type": "integer"
    },
    "billable": {
     "type": "boolean"
    }
   }
  },
  "action": {
   "enum": [
    "send",
    "send_with_caution",
    "review",
    "retry_later",
    "avoid"
   ],
   "type": "string"
  },
  "reason": {
   "type": "string"
  },
  "status": {
   "enum": [
    "valid",
    "invalid",
    "unknown",
    "temporary_unavailable",
    "syntax_error"
   ],
   "type": "string"
  },
  "signals": {
   "type": "object",
   "properties": {
    "free": {
     "type": "boolean"
    },
    "catch_all": {
     "type": "boolean"
    },
    "disposable": {
     "type": "boolean"
    },
    "role_account": {
     "type": "boolean"
    }
   }
  },
  "confidence": {
   "type": "integer",
   "maximum": 100,
   "minimum": 0
  },
  "from_cache": {
   "type": "boolean"
  },
  "request_id": {
   "type": "string",
   "example": "vrf_..."
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/inboxpolicy-send-decision-email-verification-api-96be538c/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from api.inboxpolicy.com](https://www.zero.xyz/host/api.inboxpolicy.com/llms.txt)