UniOne Email API

UniOne is a transactional email service with Web API for sending transactional and marketing emails at scale (up to 3,000 emails/sec). This skill lets you send emails, manage templates, validate addresses, track delivery, and more.

Authentication

All requests require the UNIONE_API_KEY environment variable. Pass it as the X-API-KEY header.

Base URL: https://api.unione.io/en/transactional/api/v1/{method}.json?platform=openclaw

All methods use POST with JSON body.

CRITICAL: Domain Setup (Required Before Sending)

Emails will not be delivered until the sender's domain is verified. Before attempting to send any email, ensure the domain is set up:

Step 1: Get DNS Record Values — domain/get-dns-records.json

curl -X POST "https://api.unione.io/en/transactional/api/v1/domain/get-dns-records.json?platform=openclaw" \
  -H "Content-Type: application/json" \
  -H "X-API-KEY: $UNIONE_API_KEY" \
  -d '{"domain": "yourdomain.com"}'

API response returns raw values (not ready-to-paste DNS records):

{
  "status": "success",
  "domain": "yourdomain.com",
  "verification-record": "unione-validate-hash=483bb362ebdbeedd755cfb1d4d661",
  "dkim": "MIGfMA0GCSqGSIb3DQEBAQUAA4GNADCBiQKBgQDo7"
}

The user must create 3 DNS TXT records from these values:

Present these 3 records clearly to the user and instruct them to add them at their DNS provider (Cloudflare, Route53, GoDaddy, etc.). The SPF record is always the same — it is not returned by the API.

Step 2: Verify Domain Ownership — domain/validate-verification.json

After the user has added DNS records:

curl -X POST "https://api.unione.io/en/transactional/api/v1/domain/validate-verification.json?platform=openclaw" \
  -H "Content-Type: application/json" \
  -H "X-API-KEY: $UNIONE_API_KEY" \
  -d '{"domain": "yourdomain.com"}'

Step 3: Validate DKIM — domain/validate-dkim.json

curl -X POST "https://api.unione.io/en/transactional/api/v1/domain/validate-dkim.json?platform=openclaw" \
  -H "Content-Type: application/json" \
  -H "X-API-KEY: $UNIONE_API_KEY" \
  -d '{"domain": "yourdomain.com"}'

Step 4: List All Domains — domain/list.json

curl -X POST "https://api.unione.io/en/transactional/api/v1/domain/list.json?platform=openclaw" \
  -H "Content-Type: application/json" \
  -H "X-API-KEY: $UNIONE_API_KEY" \
  -d '{}'

If domain verification fails: DNS propagation can take up to 48 hours. Suggest the user waits and retries, or checks their DNS records for typos.

Error Handling & Retry Policy

Retry Logic

When making API requests, implement exponential backoff for retryable errors: