Components

Higher-level fluent components assembled from ordinary Block Kit blocks. Components keep their output transparent: .build() returns standard Slack wire objects that can be inspected, rearranged, or mixed with other builders.

Accordion()

function Accordion(): FluentGroupBuilder<AccordionInput, JsonObject>;

Starts an accordion made from Slack-native collapsible containers.

Each section expands independently in Slack and requires no application-side interaction handler.

Chainable setters

Call these setters in any order before .build(). Repeating a singular setter replaces its previous value. Collection setters accept individual values, nested builders, or arrays and append each call.

Setter	Value type	Required	Description
.sections(...values)	JsonObject[]	Yes	Sections created with {@link AccordionSection}, in display order.

Validation and errors

.build() materializes nested builders and validates the finished Slack object. It throws a typed slackblocks validation error when a required value is missing, a value has the wrong type or range, mutually exclusive setters are combined, or Slack rejects the resulting shape. Pass { validate: false } to .build() only when intentionally creating an intermediate partial object.

Returns

FluentGroupBuilder<AccordionInput, JsonObject>

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AccordionInput

Configuration accepted by Accordion.

Properties

Property	Type	Description
sections	JsonObject[]	Sections created with AccordionSection, in display order.

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AccordionSection()

function AccordionSection(): FluentBuilder<AccordionSectionInput, JsonObject>;

Creates one Slack-native collapsible container for an Accordion. Set a heading and child blocks, then optionally add supporting copy, an icon, width, divider behavior, or an initially expanded state.

Chainable setters

Call these setters in any order before .build(). Repeating a singular setter replaces its previous value. Collection setters accept individual values, nested builders, or arrays and append each call.

Setter	Value type	Required	Description
.title(value)	TextLike	Yes	Plain-text heading shown above the collapsible content.
.blocks(...values)	JsonObject[]	Yes	Blocks revealed when the section is expanded.
.subtitle(value)	TextLike	No	Optional supporting copy below the heading.
.icon(value)	JsonObject	No	Optional image displayed in the header.
.expanded(value)	boolean	No	Whether this section starts expanded. Defaults to false.
.width(value)	ContainerWidth	No	Horizontal width of this section. Defaults to standard.
.hasHeaderDivider(value)	boolean	No	Whether Slack draws a divider below the header.
.blockId(value)	string	No	Optional deterministic identifier for this section.

Validation and errors

.build() materializes nested builders and validates the finished Slack object. It throws a typed slackblocks validation error when a required value is missing, a value has the wrong type or range, mutually exclusive setters are combined, or Slack rejects the resulting shape. Pass { validate: false } to .build() only when intentionally creating an intermediate partial object.

Returns

FluentBuilder<AccordionSectionInput, JsonObject>

---

AccordionSectionInput

Configuration accepted by AccordionSection.

Properties

Property	Type	Description
blockId?	string	Optional deterministic identifier for this section.
blocks	JsonObject[]	Blocks revealed when the section is expanded.
expanded?	boolean	Whether this section starts expanded. Defaults to false.
hasHeaderDivider?	boolean	Whether Slack draws a divider below the header.
icon?	JsonObject	Optional image displayed in the header.
subtitle?	TextLike	Optional supporting copy below the heading.
title	TextLike	Plain-text heading shown above the collapsible content.
width?	ContainerWidth	Horizontal width of this section. Defaults to standard.

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Paginator()

function Paginator(): FluentGroupBuilder<PaginatorInput, JsonObject>;

Starts a pure paginator component.

The component renders the selected page plus ordinary context and action blocks. Generated button values contain the one-based page to render next; interaction handling remains in the application.

Chainable setters

Call these setters in any order before .build(). Repeating a singular setter replaces its previous value. Collection setters accept individual values, nested builders, or arrays and append each call.

Setter	Value type	Required	Description
.blocks(...values)	JsonObject[]	Yes	Blocks to paginate, in display order.
.actionIdPrefix(value)	string	Yes	Prefix used for the generated previous and next action identifiers.
.page(value)	number	No	One-based page to render. Defaults to 1.
.pageSize(value)	number	No	Blocks displayed per page. Defaults to 5.
.previousText(value)	string	No	Label for the previous-page button. Defaults to Previous.
.nextText(value)	string	No	Label for the next-page button. Defaults to Next.
.showPageIndicator(value)	boolean	No	Whether to render Page n of m above the controls. Defaults to true.
.blockId(value)	string	No	Optional identifier for the generated actions block.

Validation and errors

.build() materializes nested builders and validates the finished Slack object. It throws a typed slackblocks validation error when a required value is missing, a value has the wrong type or range, mutually exclusive setters are combined, or Slack rejects the resulting shape. Pass { validate: false } to .build() only when intentionally creating an intermediate partial object.

Returns

FluentGroupBuilder<PaginatorInput, JsonObject>

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PaginatorInput

Configuration accepted by Paginator.

Properties

Property	Type	Description
actionIdPrefix	string	Prefix used for the generated previous and next action identifiers.
blockId?	string	Optional identifier for the generated actions block.
blocks	JsonObject[]	Blocks to paginate, in display order.
nextText?	string	Label for the next-page button. Defaults to Next.
page?	number	One-based page to render. Defaults to 1.
pageSize?	number	Blocks displayed per page. Defaults to 5.
previousText?	string	Label for the previous-page button. Defaults to Previous.
showPageIndicator?	boolean	Whether to render Page n of m above the controls. Defaults to true.