# is-email-hosted-by-postmark-bulk

> is-email-hosted-by-postmark-bulk is a paid API for AI agents from email.intel.rallylive.ca, paid per call via x402, $0.1/call, status unknown (last checked 2026-10-22).

Checks up to 20 domains at once to determine if each domain's email is hosted by Postmark, returning concurrent results with per-item error fields and a failure count.

## Facts

- Endpoint: GET https://email.intel.rallylive.ca/bulk/email/hosted-by/postmark?utm_source=zero.xyz
- Price: $0.1/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/is-email-hosted-by-postmark-bulk-730843ce
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_PNKu3qdUk-4WR80eXVTKK

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 is-email-hosted-by-postmark-bulk-730843ce
```

Example prompt: Check whether these domains are hosted by Postmark for email: stripe.com, twilio.com, sendgrid.com, mailchimp.com, and github.com — I need results for all of them at once.

## When to prefer this

Use this endpoint when you have a list of 2–20 domains and need to check Postmark hosting status for all of them in a single call, rather than making individual requests per domain. It's ideal for lead enrichment pipelines, competitive analysis, or any workflow where you need batch domain intelligence about Postmark usage without the overhead of sequential single-domain calls.

## Known failure modes

- DNS lookup failure for one or more domains (per-item error field populated)
- Invalid or malformed domain names in the input list
- Input list exceeds 20 domains limit
- Network timeout during concurrent MX resolution
- Domain has no MX records configured

## How this service works

Bulk is email hosted by postmark: up to 20 domains in one call, processed concurrently, results in input order with a per-item error field and a failure count. Same answer per item as the single endpoint. Batch enrichment for agents that hold a list. $0.10 per batch.

## Output

An ordered array of results corresponding to each input domain, where each item indicates whether the domain's email is hosted by Postmark (based on MX record matching via Cloudflare DoH), plus a per-item error field for any lookup failures and an overall failure count for the batch.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "$schema": "https://json-schema.org/draft/2020-12/schema",
 "required": [
  "input"
 ],
 "properties": {
  "input": {
   "type": "object",
   "required": [
    "type",
    "method"
   ],
   "properties": {
    "type": {
     "type": "string",
     "const": "http"
    },
    "method": {
     "enum": [
      "GET"
     ],
     "type": "string"
    },
    "queryParams": {
     "type": "object",
     "properties": {}
    }
   },
   "additionalProperties": false
  },
  "output": {
   "type": "object",
   "required": [
    "type"
   ],
   "properties": {
    "type": {
     "type": "string"
    },
    "example": {
     "type": "object"
    }
   }
  }
 }
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/is-email-hosted-by-postmark-bulk-730843ce/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from email.intel.rallylive.ca](https://www.zero.xyz/host/email.intel.rallylive.ca/llms.txt)