You can now create invoices independently of contracts:

• POST /invoices now supports creating standalone invoices with full item details
• Added send_to_customer parameter to automatically email invoices upon creation

Breaking Change: The API now uses snake_case consistently for all field names and SNAKE_CASE for enum values.

Examples of changed fields:

• priceType → price_type
• externalId → external_id
• customerId → customer_id

Update your integration to use the new field names.

Full accounts payable management is now available:

Vendors

• GET /vendors - List all vendors
• POST /vendors - Create a vendor
• GET /vendors/{id} - Retrieve a vendor
• PUT /vendors/{id} - Update a vendor
• DELETE /vendors/{id} - Delete a vendor

Bills

• GET /bills - List all bills
• POST /bills - Create a bill
• GET /bills/{id} - Retrieve a bill
• PUT /bills/{id} - Update a bill
• DELETE /bills/{id} - Delete a bill

All list endpoints now support cursor-based pagination:

• Use limit parameter to control page size (default varies by endpoint)
• Use cursor parameter to retrieve subsequent pages
• Responses include a pagination object with a cursor field for the next page

This applies to: /products, /customers, /contracts, /invoices, /vendors, /bills

Breaking Change: All list endpoints now return an object wrapper instead of a raw array.

Before:

[{ "id": "..." }, { "id": "..." }]

After:

{
  "data": [{ "id": "..." }, { "id": "..." }],
  "pagination": { "cursor": "..." }
}

Update your integration to access the data property for the list of items.

Added support for usage-based pricing models:

• Products can now have usage-based price types
• Contracts support usage commitments for metered billing

All major entities now support external references, allowing you to link Rillet records to your external systems:

• Customers, Contracts, Invoices, and Products include an external_references array
• Each reference has a type, id, and optional url
• Use external references to maintain mappings between Rillet and your CRM, ERP, or other systems

You can now amend existing contracts through the API:

• POST /contracts/{id}/amendments - Amend a contract

The amendment request allows you to add new items, modify existing items, and update contract terms including dates and invoicing schedules.

Track usage-based billing with the new usage records endpoints:

• POST /contract-items/{id}/usage - Create a usage record
• GET /contract-items/{id}/usage - List all usage records for a contract item
• DELETE /contract-items/{id}/usage - Delete a usage record

Full invoice lifecycle management is now available:

• GET /invoices - List all invoices
• POST /invoices - Create an invoice
• GET /invoices/{id} - Retrieve an invoice
• PUT /invoices/{id} - Update an invoice
• DELETE /invoices/{id} - Delete an invoice