> For the complete documentation index, see [llms.txt](https://docs.apinity.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.apinity.io/step-by-step/subscribe-and-consume-a-service.md).

# Subscribe and Consume a Service

## Quick Start

For a brief overview check out [Consume a Service - quick overview](/quick-start/consume-a-service-quick.md)

## Overview

**Definition**: Subscriptions are the contractual and technical relationship between a Consumer and a Provider. By subscribing to a service the consumer enters a relationship with the providers which is defined by the details of the plan and the service.

<figure><img src="/files/KN08hANbbPNaGuBvhpsY" alt=""><figcaption><p>click image to enlarge</p></figcaption></figure>

Subscriptions are the central entity for consuming services on the marketplace. The subscription (and its unique ID) represent one relationship between a provider and a consumer.

**Technical integration:** For each subscription, there is a unique technical ID and Base URL on the marketplace. This means, the technical integration will always remain the same, even if commercial aspects of the contract change.

**Consumer clients:** Consumers can manage access to their subscriptions via consumer clients. These are separately defined authentication keys that can be freely assigned/unassigned to subscriptions. One or more consumer clients can be assigned to one subscription, e.g. for granting access to the same service for individual teams or different applications. One consumer client can also be assigned to multiple subscriptions.

**Plans:** Plans determine the technical and commercial aspects of a service. Different plans can have different prices, limits or transactions. When subscribing, the consuming partner can chose the best fitting plan. The plan can be changed later without breaking the integration if both, provider and consumer agree.


---

# 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 dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.apinity.io/step-by-step/subscribe-and-consume-a-service.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

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.