# REST API placeholders

> The placeholders that stand in for values in Cascade CMS REST API endpoint documentation — {auth} for credentials, {identifier} for the asset being addressed, and {wsdl} for the operation's message body.

URL: https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/rest-api/placeholders/index.html
category: Developing in Cascade
article-type: concept
content-kind: article
release-availability: all
tags: api
updated: 2026-10-06

Endpoints throughout the REST API documentation are written with placeholders in braces rather than real values — `/api/v1/read/{identifier}?{auth}`, for example. Each placeholder stands for a value you supply, and each one has its own rules.

## The placeholders

- [`{auth}`](https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/rest-api/placeholders/auth.html) — how you authenticate the request, either as URL parameters or in the message body.
- [`{identifier}`](https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/rest-api/placeholders/identifier.html) — which asset the operation acts on, given either as a path or as an id.
- [`{wsdl}`](https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/rest-api/placeholders/wsdl.html) — the structure the operation's message body has to conform to.

See [Operations](https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/rest-api/operations.html) for the full endpoint list, and [REST API](https://www.hannonhill.com/cascadecms/latest/articles/developing-in-cascade/rest-api/index.html) for how the API compares to SOAP Web Services.