> ## Documentation Index
> Fetch the complete documentation index at: https://docs.momentco.io/llms.txt
> Use this file to discover all available pages before exploring further.

# Metadata

> Learn how to pass additional information using Metadata

### Metadata

The `metadata` field is a flexible attribute available on select objects, allowing merchants to attach custom key-value pairs for internal use. This is particularly useful for associating additional contextual information—such as an order number or customer reference ID—to streamline backend operations and integrations.

> **Note:** Moment does not use metadata for any business logic. This field is solely intended for merchants to pass supplementary information.

#### Usage Restrictions

Each `metadata` object is subject to the following constraints:

* **Maximum number of key-value pairs:** 20
* **Key**: Minimum 1 character, maximum 50 characters
* **Value**: Minimum 1 character, maximum 500 characters
* **Data type**: Both `key` and `value` must be strings

<Note>
  Do not include any sensitive information in metadata, such as credit card
  numbers, bank account details, or personally identifiable information (PII).
</Note>

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