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Header block

Fields

FieldTypeDescriptionRequired?
typeStringThe type of block. For this block, type will always be header.Required
textObjectThe text for the block, in the form of a plain_text text object. Maximum length for the text in this field is 150 characters.Required
block_idStringA unique identifier for a block. If not specified, one will be generated. Maximum length for this field is 255 characters. block_id should be unique for each message and each iteration of a message. If a message is updated, use a new block_id.Optional

Usage info

A header is a plain-text block that displays in a larger, bold font. Use it to delineate between different groups of content in your app's surfaces.

Example

An example of a header block

{
"type": "header",
"text": {
"type": "plain_text",
"text": "A Heartfelt Header"
}
}