> ## Documentation Index
> Fetch the complete documentation index at: https://partner.headout.com/docs/llms.txt
> Use this file to discover all available pages before exploring further.

# Key Concepts

The concepts behind the API, grouped by the part of the integration they belong to. Read them in order for a full picture, or jump to the one you need.

Headout inventory follows a strict hierarchy, and most of what follows hangs off it:

`City → Product → Variant → Time Slot → Booking → Ticket`

> **[Integration flow](https://partner.headout.com/docs/guide/concepts/integration-flow.md)**
>
> How the hierarchy fits together, and the order a booking is built in.

> **[Products and variants](https://partner.headout.com/docs/guide/concepts/products-and-variants.md)**
>
> How products, variants and their metadata are structured, and what drives the booking form.

> **[Inventory and pricing](https://partner.headout.com/docs/guide/concepts/inventory-and-pricing.md)**
>
> Date-level availability against slot-level inventory, remaining counts, and how prices are composed.

> **[Guest details](https://partner.headout.com/docs/guide/concepts/guest-details.md)**
>
> The dynamic input fields a variant requires, and how to collect them.

> **[Booking lifecycle](https://partner.headout.com/docs/guide/concepts/booking-lifecycle.md)**
>
> The statuses a booking moves through, the transitions between them, and when tickets appear.

> **[Vouchers and tickets](https://partner.headout.com/docs/guide/concepts/vouchers-and-tickets.md)**
>
> How the voucher reaches the guest and what ticket formats to expect.

> **[Voucher API deep dive](https://partner.headout.com/docs/api-partner/v2/vouchers/understanding-the-response.md)**
>
> A section-by-section walkthrough of the voucher response — what each part holds and when it is null.

> **[Cancellation and reschedule](https://partner.headout.com/docs/guide/concepts/cancellation-and-reschedule.md)**
>
> What makes a booking amendable, how to request one, and how to observe the outcome.

> **[Webhooks](https://partner.headout.com/docs/guide/concepts/webhooks.md)**
>
> How booking updates reach you, and how to verify they came from Headout.

> **[Sandbox and production](https://partner.headout.com/docs/guide/concepts/sandbox-and-production.md)**
>
> How the two environments differ in behaviour and data.


This documentation is built and hosted on [Mintlify](https://mintlify.com), a developer documentation platform.