Developer

API Reference

Everything you need to integrate with NexusKit. Authentication, endpoints, error handling, and rate limits — all in one place.

Base URL

All API requests use the following base URL:

$https://api.nexus-kit.com

All endpoints are versioned under /v1/. Public endpoints use /v1/public/.

Authentication

NexusKit uses Bearer token authentication. Include your API key in the Authorization header:

Authorization: Bearer nk_live_abc123def456...

API Key Formats

nk_live_Production keys — use in live environments

nk_test_Test keys — use during development and staging

API keys are scoped per module. You can create read-only or read-write keys in the dashboard under Developers → API Keys.

Common Headers

Include these headers with every API request:

Header	Required	Description
Authorization	Yes	Bearer token — your API key prefixed with Bearer
X-Tenant-Id	No	Override tenant context (advanced — defaults to the key's owning tenant)
Content-Type	For POST/PATCH	Set to application/json for JSON request bodies

Error Responses

All API responses follow a consistent envelope format. Errors include a machine-readable code and a human-readable message:

{
  "data": null,
  "meta": {},
  "error": {
    "code": "VALIDATION_ERROR",
    "message": "Email is required",
    "details": {
      "field": "email",
      "reason": "missing_required"
    }
  }
}

HTTP Status	Error Code	Description
400	VALIDATION_ERROR	Request body failed validation
401	UNAUTHORIZED	Missing or invalid API key
403	FORBIDDEN	API key lacks the required scope
404	NOT_FOUND	Resource does not exist
429	RATE_LIMITED	Too many requests — slow down
500	INTERNAL_ERROR	Something went wrong on our end

Rate Limiting

To keep NexusKit fast and fair for everyone, all API requests are rate limited:

120requests per minute per IP per tenant

When you hit the limit, you'll receive a 429 Too Many Requests response. Wait a moment and retry. The response includes Retry-After headers with the number of seconds to wait.

Contact

Capture leads from website forms via API. Submissions land in your dashboard with email notifications.

Method	Path	Auth	Scope	Description
GET	/v1/contact/forms	Bearer	contact:read	List all forms for your tenant
POST	/v1/contact/forms	Bearer	contact:write	Create a new contact form
GET	/v1/contact/forms/:id/submissions	Bearer	contact:read	List submissions for a form
PATCH	/v1/contact/submissions/:id	Bearer	contact:write	Update submission status or notes
GET	/v1/contact/export.csv	Bearer	contact:read	Export submissions as CSV
POST	/v1/public/contact/forms/:id/submissions	None	—	Public — submit a form from your site

Booking

Calendar booking with services, availability slots, and appointment management.

Method	Path	Auth	Scope	Description
GET	/v1/booking/services	Bearer	booking:read	List all booking services
POST	/v1/booking/services	Bearer	booking:write	Create a new booking service
POST	/v1/booking/availability	Bearer	booking:write	Query available time slots
GET	/v1/booking/bookings	Bearer	booking:read	List all bookings
GET	/v1/booking/export.csv	Bearer	booking:read	Export bookings as CSV
GET	/v1/public/booking/services	None	—	Public — list services for embedding
GET	/v1/public/booking/services/:id/slots	None	—	Public — get available slots for a service
POST	/v1/public/booking/bookings	None	—	Public — create a booking

Links & QR

Short links and printable QR codes with privacy-safe aggregate analytics.

Method	Path	Auth	Scope	Description
GET	/v1/qr/links	Bearer	qr:read	List all short links
POST	/v1/qr/links	Bearer	qr:write	Create a new short link or QR code
GET	/v1/qr/export.csv	Bearer	qr:read	Export links and analytics as CSV
GET	/v1/public/qr/r/:slug	None	—	Public — redirect short link and track scan
GET	/v1/public/qr/:id.svg	None	—	Public — serve QR code as SVG

Onboarding

Multi-step onboarding flows with progress tracking and completion webhooks.

Method	Path	Auth	Scope	Description
GET	/v1/onboarding/flows	Bearer	onboarding:read	List all onboarding flows
POST	/v1/onboarding/flows	Bearer	onboarding:write	Create a new onboarding flow
GET	/v1/onboarding/sessions	Bearer	onboarding:read	List onboarding sessions
GET	/v1/onboarding/export.csv	Bearer	onboarding:read	Export sessions as CSV
POST	/v1/public/onboarding/sessions	None	—	Public — start a new session
PATCH	/v1/public/onboarding/sessions/:id	None	—	Public — advance session to next step

Invoices

Digital and printable invoices and receipts with email delivery.

Method	Path	Auth	Scope	Description
GET	/v1/invoice/invoices	Bearer	invoice:read	List all invoices
POST	/v1/invoice/invoices	Bearer	invoice:write	Create a new invoice
GET	/v1/invoice/invoices/:id/print	Bearer	invoice:read	Render invoice as printable PDF
GET	/v1/invoice/export.csv	Bearer	invoice:read	Export invoices as CSV

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