> For the complete documentation index, see [llms.txt](https://developer.esw.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.esw.com/inventory/inventory-api/faqs.md).

# FAQs

Answers to common questions about the Inventory API, Available-to-Sell quantities, delivery-country behavior, and error handling.

<details>

<summary>What does the Inventory API return?</summary>

The current Available-to-Sell (ATS) quantity at SKU level. ATS is inventory available for new demand, not simply physical On Hand inventory.

</details>

<details>

<summary>When should I use GET and when should I use POST?</summary>

Use GET for the complete inventory availability set for all applicable SKUs. Use POST when availability is needed for specific SKUs, or when you want to supply a delivery country. See [Decision Tables](/inventory/inventory-api/concepts/decision-tables.md).

</details>

<details>

<summary>Can I pass a delivery country to the GET endpoint?</summary>

A delivery country is not part of the documented GET contract. Use POST with `deliveryCountryIso` to get availability for a delivery market.

</details>

<details>

<summary>Do I need to know which fulfillment centres serve a country?</summary>

No. When you supply a delivery country, ESW determines the applicable inventory and manages the relevant configuration. The returned quantity is aggregated across the fulfillment centres applicable to that country.

</details>

<details>

<summary>Why can ATS differ from the stock in the warehouse?</summary>

ATS is calculated after applicable inventory controls and existing commitments. Depending on retailer configuration, it can be affected by inventory reservations, inventory already allocated to orders, Safety Stock, No Stock Overrides and other controls.

</details>

<details>

<summary>Can the quantity be negative?</summary>

No. `quantity` is an integer that is always zero or greater.

</details>

<details>

<summary>What should I do if a request fails?</summary>

Do not treat a failed request as zero inventory. A `0` is a valid zero-ATS position only when returned in a successful response. For `404` or `409`, contact ESW. For temporary failures, apply the agreed retry approach and avoid uncontrolled retries. See [Response Codes](/inventory/inventory-api/response-codes.md).

</details>


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation by asking a question.

Perform an HTTP GET request on the following URL with the `ask` and `goal` query parameters:

```
GET https://developer.esw.com/inventory/inventory-api/faqs.md?ask=<question>&goal=<user_goal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is what the user is ultimately trying to achieve, the reason they need the answer. Sharing it helps GitBook give you a better, more relevant answer. A goal is most helpful when it describes the outcome the user wants rather than restating the question. For example, with `ask=how do I create an API token`, a goal like `automate deployments from our CI pipeline` lets GitBook tailor the answer to that use case.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.