> ## Documentation Index
> Fetch the complete documentation index at: https://docs.xano.com/llms.txt
> Use this file to discover all available pages before exploring further.
# XanoScript for Addons
> Define addons in XanoScript to create reusable database query components
export const xanoscriptApiInputsDiagram = `
\`\`\`mermaid
flowchart TB
A[Declaration] --> B[Input]
B --> C[Stack]
C --> D[Response]
D --> E[Settings]
style A fill:#cdeaff,stroke:#0077cc,stroke-width:2px
style B fill:#f5f5f5,stroke:#ccc,stroke-width:1px
style C fill:#f5f5f5,stroke:#ccc,stroke-width:1px
style D fill:#f5f5f5,stroke:#ccc,stroke-width:1px
style E fill:#f5f5f5,stroke:#ccc,stroke-width:1px
\`\`\`
`;
export function SideBySide({diagram, children}) {
return
;
};
Please note that while in the visual builder, you can create addons directly from a database query statement. However, when working in XanoScript, you must manually define the addon before adding it to another database query.
## Introduction
The `addon` primitive lets you define reusable database query components using XanoScript. Addons are specifically used alongside existing database queries to enrich the data with related data from other tables.
Each addon corresponds to a **database query** that you can reuse across multiple APIs, functions, or other components — but expressed in code.
Addons will typically:
* Declare their **name** and **description**
* Accept **inputs** for query parameters
* Run a **database query** in the stack
* Return the **query results** directly
***
## Anatomy
Every XanoScript addon follows a predictable structure.
Unlike other primitives, addons have a simplified structure focused on database queries. They contain input parameters, a database query stack, and optional settings.
Here's an example of a fully defined addon in XanoScript:
```javascript XanoScript lines icon="code" theme={null}
// Gets all comments from a specific user.
addon comment {
input {
int user_id?
}
stack {
db.query comment {
search = $db.comment.user_id == $input.user_id
return = {type: "list"}
}
}
tags = ["database", "user data"]
}
```
***
## Key Characteristics
**Database Query Only**: Addons can only contain database queries (`db.query` or `db.get`) in their stack. No other function types are allowed.
**No Response Block**: Addons automatically return whatever the database query returns. The return value is determined by the `return` parameter:
* `{type: "list"}` — Returns an array of records
* `{type: "single"}` — Returns a single record
* `{type: "count"}` — Returns the count of matching records
* `{type: "aggregate"}` — Returns an aggregation of the records
**Reusable Components**: Perfect for creating reusable query logic that can be called from other functions or APIs.
***
## Parameter Definition
| Parameter | Required | Description |
| ------------- | -------- | -------------------------------------------------------------------------------------------------------------------- |
| `description` | no | A short summary of the addon. May also appear as a “//” comment above the block. |
| | | **Example:** `description = "Gets all comments from a specific user"` |
| `input` | no | Input parameters for the database query. |
| | | **Example:** `input { int user_id? }` |
| `stack` | ✅ | Database query that will be executed. Must contain only `db.query` or `db.get` functions. |
| | | **Example:** `stack { db.query comment { search = $db.comment.user_id == $input.user_id return = {type: "list"} } }` |
| `tags` | no | A list of tags used to categorize and organize the addon in your workspace. |
| | | **Example:** `tags = ["database", "user data"]` |
***
## What's Next
Now that you understand how to define addons in XanoScript, here are a few great next steps:
Learn about the database functions available in the stack to create more complex queries.
Use the XanoScript VS Code extension with Copilot to write XanoScript in your favorite IDE.
Use addons in your API endpoints to create reusable database query components.