Inbox
Developers
API keys
Authenticate against the public API with a bearer key. Keys are shown once at creation.
Webhooks
Receive signed POST events at your endpoint. Signature: HMAC SHA-256 of the raw body with your webhook secret, sent as X-NLS-Signature.
Quick start
Base URL is this portal's domain. Replace the key with your own.
# List inbox messages
curl -H "Authorization: Bearer nlk_your_key" \
https://inbox.nextlevelsites.com/v1/messages?folder=inbox
# Send an email
curl -X POST https://inbox.nextlevelsites.com/v1/send \
-H "Authorization: Bearer nlk_your_key" \
-H "Content-Type: application/json" \
-d '{"to": "someone@example.com", "subject": "Hello", "html": "<p>Sent via the API</p>"}'
# Webhook events: message.sent, message.received, test.ping
# Verify: X-NLS-Signature = sha256=HMAC_SHA256(raw_body, webhook_secret)
Settings
These details power your invoices, email signatures, and the assistant. It uses them so you do not have to repeat yourself.
List your packages so the assistant can invoice by name. Say "invoice them for the onboarding package" and it knows the price.
Connect outside services so the assistant can act on them. Setup requires an OAuth app per provider.
Media
Tools
Tracked link
Fill the form to build a link
Use tracked links in the emails you send from here so your analytics tool attributes visits and sales to the right campaign. Works with any analytics platform that reads UTM parameters.