> For the complete documentation index, see [llms.txt](https://docs.loadmill.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.loadmill.com/reporting/api-catalog-and-coverage/api-catalog/unique-entity-ids-mapping.md).

# Unique Entity ID's Mapping

Custom id patterns, such as prefixed/suffixed IDs may be not recognized automatically during the mapping stage. Use entity IDs mapping settings to prevent duplicate APIs, to streamline catalog organization and when you recognize static IDs in the api-catalog.

<figure><img src="/files/0H2ZlXJCxqUWPDYINUYu" alt=""><figcaption><p>Policy id wasn't automatically mapped as it is custom prefixed</p></figcaption></figure>

Here are the steps to map the ID:

1. Head to settings, in the dotted menu at the top-right corner of the screen\
   ![](/files/zGVv08PuLurlzA4mOLDp)
2. Select 'PER-SERVICE' tab and insert a unique regular-expression into 'Ids Path Regexes'.

<figure><img src="/files/HgAabV5f70B34z1yq7oL" alt=""><figcaption><p>In our case, the id prefixed with 'cust' followed with four digits (<code>cust\d{4}</code>)</p></figcaption></figure>

3. Select 'Apply changes to existing APIs' in order to re-map existing api's and click on save.\\

   <figure><img src="/files/Iz0INNDct9EH1dck2OLL" alt=""><figcaption><p>The result will show one unified endpoint with a placeholder for the id.</p></figcaption></figure>

Notes:

* Loadmill tracks changes in the API-catalog, a previous state can be achieved by selecting "Undo Settings Changes" in the top right corner dotted menu.\
  ![](/files/fuNeKEKI36yvbN38L0aO)
* The id is evaluated on individual part of the path in the url, the specified regex should match just the id part between/after the slash/es.


---

# 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.loadmill.com/reporting/api-catalog-and-coverage/api-catalog/unique-entity-ids-mapping.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.