# Substance Defining Attributes

The following defining attributes correspond to the *Substance Attribute Summary* table.

## Has disposition

This attribute enables the creation of an association between a substance concept and a disposition. A disposition is defined as a behavior that a substance will exhibit or participate in, given the appropriate context.

## Is modification of

This attribute indicates that the concept is a structural modification of another concept, and that the substance's intrinsic physicochemical properties remain unchanged.

<a href="https://docs.google.com/forms/d/e/1FAIpQLScTmbZIf0UEQwYDkY27EEWBkaiYkHSbR0_9DmFrMLXoQLyL7Q/viewform?usp=pp_url&#x26;entry.1767247133=SCT+Editorial+Guide&#x26;entry.670899847=Substance%20Defining%20Attributes" class="button primary">Provide Feedback</a>


---

# Agent Instructions: 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:

```
GET https://docs.snomed.org/snomed-ct-specifications/snomed-ct-editorial-guide/readme/authoring/domain-specific-modeling/substance/substance-defining-attributes.md?ask=<question>
```

The question should be specific, self-contained, and written in natural language.
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.