# HALOWERK buerowerk – Per-Domain Email Import Quota Filter

> HALOWERK buerowerk – Per-Domain Email Import Quota Filter is a paid API for AI agents from buero.halowerk.com, paid per call via x402, $0.004/call, status unknown (last checked 2026-10-22).

Filters a list of email addresses so that no single domain exceeds a specified maximum count, enforcing per-domain import quotas.

## Facts

- Endpoint: POST https://buero.halowerk.com/v1/baumarkt/mail/per-domain-import-quota?utm_source=zero.xyz
- Price: $0.004/call
- Payment: x402
- Status: unknown
- Last checked: 2026-10-22
- Activations on Zero: 0
- Tags: x402
- Canonical page: https://www.zero.xyz/c/halowerk-buerowerk-per-domain-email-import-quota-filter-7320fee6
- Structured record (JSON): https://api.zero.xyz/v1/capabilities/cap_t1HbvapyQzKJTwyPIEKOI

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 halowerk-buerowerk-per-domain-email-import-quota-filter-7320fee6 -d '<json body>'
```

Example prompt: I have a list of 300 email addresses I want to import into our system — can you filter it so that no single domain contributes more than 10 addresses?

## When to prefer this

Choose this endpoint when you need a lightweight, paid-per-call microservice to enforce per-domain caps on email lists before import or mailing — particularly useful in automated pipelines where fairness or anti-spam constraints must be applied server-side without building custom filtering logic.

## Known failure modes

- Empty emails array returns validation error
- max_per_domain below 1 or above 500 returns schema violation
- emails array exceeds 500 items returns rejection
- Malformed email strings may be rejected or silently skipped
- Payment failure over x402 protocol returns 402 with payment details
- Network timeout on large lists

## How this service works

HALOWERK buerowerk — bezahlte Endpunkte nach x402. Preise in USDC auf Base Mainnet.

## Output

A processed JSON response indicating which email addresses passed the per-domain quota filter, effectively returning a trimmed list where each domain is represented by at most the specified maximum number of addresses.

## Request schema (JSON Schema)

```json
{
 "type": "object",
 "properties": {
  "emails": {
   "type": "array",
   "items": {
    "type": "string",
    "maxLength": 320,
    "minLength": 1
   },
   "maxItems": 500,
   "minItems": 1
  },
  "max_per_domain": {
   "type": "integer",
   "maximum": 500,
   "minimum": 1
  }
 }
}
```

## Response schema (JSON Schema)

```json
{
 "type": "json"
}
```

## More

- Live health (JSON, refreshed every minute): https://www.zero.xyz/c/halowerk-buerowerk-per-domain-email-import-quota-filter-7320fee6/health.json
- [Zero catalog index](https://www.zero.xyz/llms.txt)
- [Other services from buero.halowerk.com](https://www.zero.xyz/host/buero.halowerk.com/llms.txt)