Composition Objects
Fluent builders for reusable composition objects nested inside blocks and elements. This includes text, selectable options, confirmation dialogs, files, workflow metadata, rich text, table cells, and chart data.
See: https://docs.slack.dev/reference/block-kit/composition-objects.
AreaChart()
function AreaChart(): FluentBuilder<AxisChartBuilderInput, SlackObject<"area">>;
Creates a layered area chart for a data visualization block. Supply one or more named series and an axis configuration whose categories match every point in those series.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
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 |
|---|---|---|---|
.series(...values) | | Yes | One or more named data series to plot. |
.axisConfig(value) | | Yes | Axis labels and category configuration. |
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<AxisChartBuilderInput, SlackObject<"area">>
AxisConfig()
function AxisConfig(): FluentBuilder<AxisConfigInput, JsonObject>;
Creates category labels and optional axis titles for a bar, area, or line chart. Categories must be unique and match the labels represented in every data series.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
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 |
|---|---|---|---|
.categories(...values) | string[] | Yes | Unique category labels, in display order. |
.xLabel(value) | string | No | Optional horizontal-axis label, up to 50 characters. |
.yLabel(value) | string | No | Optional vertical-axis label, up to 50 characters. |
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<AxisConfigInput, JsonObject>
AxisConfigInput
Ordered unique categories and optional axis titles shared by every series in an axis- based chart.
Properties
BarChart()
function BarChart(): FluentBuilder<AxisChartBuilderInput, SlackObject<"bar">>;
Creates a grouped bar chart for a data visualization block. Supply one or more named series and an axis configuration whose categories match every point in those series.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
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 |
|---|---|---|---|
.series(...values) | | Yes | One or more named data series to plot. |
.axisConfig(value) | | Yes | Axis labels and category configuration. |
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<AxisChartBuilderInput, SlackObject<"bar">>
ChartSegment()
function ChartSegment(): FluentBuilder<ChartSegmentInput, JsonObject>;
Creates one labelled, positive-valued segment in a pie chart. Segment labels are limited to 20 characters and each value must be a finite number greater than zero.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.label(value) | string | Yes | Segment label, up to 20 characters. |
.value(value) | number | Yes | Positive finite segment value. |
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<ChartSegmentInput, JsonObject>
ChartSegmentInput
Label and positive finite value for one segment in a Slack-rendered pie chart.
Properties
| Property | Type | Description |
|---|---|---|
label | string | Segment label, up to 20 characters. |
value | number | Positive finite segment value. |
ColumnSettings()
function ColumnSettings(): FluentBuilder<{
align?: "left" | "center" | "right";
isWrapped?: boolean;
}, JsonObject>;
Creates display settings for one column in a table block. Configure horizontal alignment and whether long cell content should wrap within the column.
See: https://docs.slack.dev/reference/block-kit/blocks/table-block.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.align(value) | "left" | "center" | "right" | No | Horizontal cell alignment. |
.isWrapped(value) | boolean | No | Whether long cell content wraps. |
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<{
align?: "left" | "center" | "right";
isWrapped?: boolean;
}, JsonObject>
Confirmation()
function Confirmation(): FluentBuilder<ConfirmationInput, JsonObject>;
Creates a confirmation dialog that asks a user to approve or cancel an interactive action. Configure its title, explanatory text, and the labels on both the confirm and deny buttons.
See: https://docs.slack.dev/reference/block-kit/composition-objects/confirmation-dialog-object.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.title(value) | | Yes | Plain-text dialog title, up to 100 characters. |
.text(value) | | Yes | Confirmation question, up to 300 characters. |
.confirm(value) | | Yes | Plain-text confirm-button label, up to 30 characters. |
.deny(value) | | Yes | Plain-text cancel-button label, up to 30 characters. |
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<ConfirmationInput, JsonObject>
ConfirmationInput
Text and button labels required to present a confirmation step before an interactive action is submitted.
Properties
| Property | Type | Description |
|---|---|---|
confirm | TextLike | Plain-text confirm-button label, up to 30 characters. |
deny | TextLike | Plain-text cancel-button label, up to 30 characters. |
text | TextLike | Confirmation question, up to 300 characters. |
title | TextLike | Plain-text dialog title, up to 100 characters. |
ConversationFilter()
function ConversationFilter(): FluentBuilder<{
excludeBotUsers?: boolean;
excludeExternalSharedChannels?: boolean;
include?: string[];
}, JsonObject>;
Creates a filter for conversation single-select and multi-select elements. Include selected conversation kinds and optionally exclude externally shared channels or direct messages with bots; at least one filter field is required.
See: https://docs.slack.dev/reference/block-kit/composition-objects/conversation-filter-object.
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 |
|---|---|---|---|
.include(...values) | string[] | No | One or more conversation kinds to include: im, mpim, private, or public. |
.excludeExternalSharedChannels(value) | boolean | No | Exclude externally shared conversations. |
.excludeBotUsers(value) | boolean | No | Exclude direct messages with bots. |
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<{
excludeBotUsers?: boolean;
excludeExternalSharedChannels?: boolean;
include?: string[];
}, JsonObject>
DataPoint()
function DataPoint(): FluentBuilder<DataPointInput, JsonObject>;
Creates one labelled numeric point in a bar, area, or line chart series. Its label must correspond to one of the chart's axis categories and its value must be finite.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.label(value) | string | Yes | Category label, up to 20 characters. |
.value(value) | number | Yes | Finite numeric value. |
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<DataPointInput, JsonObject>
DataPointInput
Category label and finite numeric value for one point in an axis-based chart series.
Properties
| Property | Type | Description |
|---|---|---|
label | string | Category label, up to 20 characters. |
value | number | Finite numeric value. |
DataSeries()
function DataSeries(): FluentBuilder<DataSeriesInput, JsonObject>;
Creates a named series containing between one and 20 data points for a bar,
area, or line chart. Add points in display order with repeated data() calls.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
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 |
|---|---|---|---|
.name(value) | string | Yes | Unique series name, up to 20 characters. |
.data(...values) | | Yes | Between one and 20 points created with DataPoint(). |
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<DataSeriesInput, JsonObject>
DataSeriesInput
Unique name and ordered data points for one series in a bar, area, or line chart.
Properties
| Property | Type | Description |
|---|---|---|
data | JsonObject[] | Between one and 20 points created with dataPoint. |
name | string | Unique series name, up to 20 characters. |
DispatchActionConfiguration()
function DispatchActionConfiguration(): FluentBuilder<{
triggerActionsOn: string[];
}, JsonObject>;
Creates a dispatch-action configuration for an input element. Select the input
events, such as Enter being pressed or a character being entered, that should
immediately send a block_actions payload to the application.
See: https://docs.slack.dev/reference/block-kit/composition-objects/dispatch-action-configuration-object.
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 |
|---|---|---|---|
.triggerActionsOn(...values) | string[] | Yes | One or two events such as on_enter_pressed or on_character_entered. |
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<{
triggerActionsOn: string[];
}, JsonObject>
InputParameter()
function InputParameter(): FluentBuilder<{
name: string;
value: string;
}, JsonObject>;
Creates one customizable input parameter passed to a Slack workflow trigger. The parameter name must match an input defined by the workflow, and its value is supplied when the workflow button is used.
See: https://docs.slack.dev/reference/block-kit/composition-objects/workflow-object.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.name(value) | string | Yes | Workflow parameter name. |
.value(value) | string | Yes | Value passed to the workflow. |
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<{
name: string;
value: string;
}, JsonObject>
LineChart()
function LineChart(): FluentBuilder<AxisChartBuilderInput, SlackObject<"line">>;
Creates a line chart for a data visualization block. Supply one or more named series and an axis configuration whose categories match every point in those series.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
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 |
|---|---|---|---|
.series(...values) | | Yes | One or more named data series to plot. |
.axisConfig(value) | | Yes | Axis labels and category configuration. |
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<AxisChartBuilderInput, SlackObject<"line">>
Markdown()
function Markdown(): FluentBuilder<MarkdownBuilderInput, TextObject>;
Creates a text composition object rendered with Slack's mrkdwn syntax. Use
verbatim() when links, mentions, and other tokens should remain literal
rather than being parsed automatically.
See: https://docs.slack.dev/reference/block-kit/composition-objects/text-object.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.text(value) | string | Yes | Slack mrkdwn text to display. |
.verbatim(value) | boolean | No | Whether Slack should treat the text literally instead of auto-parsing links and mentions. |
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<MarkdownBuilderInput, TextObject>
MarkdownOptions
Optional parsing behavior for a mrkdwn text object, controlling automatic links and
mentions.
Properties
| Property | Type | Description |
|---|---|---|
verbatim? | boolean | Whether Slack should treat the text literally instead of auto-parsing links and mentions. |
Option()
function Option(): FluentBuilder<OptionInput, JsonObject>;
Creates one selectable item for a select menu, multi-select menu, checkbox
group, radio-button group, or overflow menu. The application-defined value
is returned when the user chooses the option.
See: https://docs.slack.dev/reference/block-kit/composition-objects/option-object.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.text(value) | | Yes | Plain-text option label, up to 75 characters. |
.value(value) | string | Yes | Application-defined value, up to 150 characters. |
.description(value) | | No | Optional plain-text supporting copy, up to 75 characters. |
.url(value) | string | No | Optional destination URL for overflow menus. |
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<OptionInput, JsonObject>
OptionGroup()
function OptionGroup(): FluentBuilder<OptionGroupInput, JsonObject>;
Creates a labelled group containing between one and 100 selectable options. Option groups can organize choices in static single-select and multi-select menus.
See: https://docs.slack.dev/reference/block-kit/composition-objects/option-group-object.
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 |
|---|---|---|---|
.label(value) | | Yes | Plain-text group label, up to 75 characters. |
.options(...values) | | Yes | Between one and 100 option objects. |
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<OptionGroupInput, JsonObject>
OptionGroupInput
Label and choices for a group of between one and 100 options in a static select menu.
Properties
| Property | Type | Description |
|---|---|---|
label | TextLike | Plain-text group label, up to 75 characters. |
options | JsonObject[] | Between one and 100 option objects. |
OptionInput
Label, returned value, and optional supporting content for one selectable option.
Properties
| Property | Type | Description |
|---|---|---|
description? | TextLike | Optional plain-text supporting copy, up to 75 characters. |
text | TextLike | Plain-text option label, up to 75 characters. |
url? | string | Optional destination URL for overflow menus. |
value | string | Application-defined value, up to 150 characters. |
PieChart()
function PieChart(): FluentBuilder<{
segments: JsonObject[];
}, SlackObject<"pie">>;
Creates a pie chart containing between one and 12 labelled segments for a data
visualization block. Add built segments or ChartSegment builders with
repeated segments() calls.
See: https://docs.slack.dev/reference/block-kit/blocks/data-visualization-block.
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 |
|---|---|---|---|
.segments(...values) | | Yes | — |
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<{
segments: JsonObject[];
}, SlackObject<"pie">>
PlainText()
function PlainText(): FluentBuilder<PlainTextBuilderInput, TextObject>;
Creates a plain-text composition object with no Slack formatting. Use it for
labels and other fields that require plain_text; emoji shortcodes can be
converted by enabling the optional emoji setting.
See: https://docs.slack.dev/reference/block-kit/composition-objects/text-object.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.text(value) | string | Yes | Text to display. |
.emoji(value) | boolean | No | Whether Slack should render emoji shortcodes. |
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<PlainTextBuilderInput, TextObject>
PlainTextOptions
Optional rendering behavior for a plain-text object, controlling whether Slack expands emoji shortcodes.
Properties
| Property | Type | Description |
|---|---|---|
emoji? | boolean | Whether Slack should render emoji shortcodes. |
RawNumber()
function RawNumber(): FluentBuilder<{
text: string;
value: number;
}, SlackObject<"raw_number">>;
Creates a numeric data-table cell with separate machine-sortable and
human-readable values. The numeric value must be finite, while text() controls
what Slack displays to the reader.
See: https://docs.slack.dev/reference/block-kit/blocks/data-table-block.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.value(value) | number | Yes | — |
.text(value) | string | Yes | — |
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<{
text: string;
value: number;
}, SlackObject<"raw_number">>
RawText()
function RawText(): FluentBuilder<{
text: string;
}, SlackObject<"raw_text">>;
Creates an unformatted raw_text cell for a table or data table. Slack displays
the supplied text literally, without applying mrkdwn or rich-text formatting.
See: https://docs.slack.dev/reference/block-kit/blocks/table-block.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.text(value) | string | Yes | — |
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<{
text: string;
}, SlackObject<"raw_text">>
RichText()
function RichText(): FluentBuilder<RichTextBuilderInput, JsonObject>;
Creates the core text run used by Slack's structured rich-text API. Apply bold, italic, strikethrough, or code styling and place the result inside a rich-text section, list, code block, or quote.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#text-element-type.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.text(value) | string | Yes | Text content for this run. |
.style(value) | | No | Optional Slack rich-text styling. |
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<RichTextBuilderInput, JsonObject>
RichTextChannel()
function RichTextChannel(): FluentBuilder<RichTextMentionBuilderInput, JsonObject>;
Creates a structured rich-text mention for a Slack channel, such as #general.
Slack resolves the supplied channel ID when rendering the containing rich-text
block.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#channel-element-type.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.id(value) | string | Yes | Slack channel, user, or user-group identifier. |
.style(value) | | No | Optional Slack rich-text styling. |
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<RichTextMentionBuilderInput, JsonObject>
RichTextCodeBlock()
function RichTextCodeBlock(): FluentBuilder<RichTextLayoutBuilderInput, JsonObject>;
Creates a preformatted rich-text code block, roughly equivalent to a fenced code block in Markdown. Add structured rich-text elements as its content and optionally configure the surrounding border.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#rich_text_preformatted.
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 |
|---|---|---|---|
.elements(...values) | | Yes | Rich-text elements displayed inside the layout. |
.border(value) | number | No | Optional border width. |
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<RichTextLayoutBuilderInput, JsonObject>
RichTextEmoji()
function RichTextEmoji(): FluentBuilder<{
name: string;
}, JsonObject>;
Creates a structured rich-text emoji using a built-in Slack name or a custom workspace emoji name. Supply the name without surrounding colon characters.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#emoji-element-type.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.name(value) | string | Yes | — |
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<{
name: string;
}, JsonObject>
RichTextLink()
function RichTextLink(): FluentBuilder<{
style?: RichTextStyle;
text?: string;
unsafe?: boolean;
url: string;
}, JsonObject>;
Creates a structured rich-text link with a destination URL and optional display text or style. When text is omitted, Slack displays the URL itself.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#link-element-type.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.url(value) | string | Yes | Destination URL. |
.text(value) | string | No | Optional visible label. Slack displays the URL when omitted. |
.unsafe(value) | boolean | No | Mark a URL as unsafe when mirroring a Slack-provided payload. |
.style(value) | | No | Optional inline formatting. |
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<{
style?: RichTextStyle;
text?: string;
unsafe?: boolean;
url: string;
}, JsonObject>
RichTextList()
function RichTextList(): FluentBuilder<{
border?: number;
elements: JsonObject[];
indent?: number;
offset?: number;
style: "bullet" | "ordered";
}, JsonObject>;
Creates an ordered or bulleted list of rich-text sections. Configure indentation
and list style, then add each section with elements() in display order.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#rich_text_list.
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 |
|---|---|---|---|
.elements(...values) | | Yes | Rich-text section objects used as list items. |
.style(value) | "bullet" | "ordered" | Yes | List marker style. |
.indent(value) | number | No | Nesting depth. |
.offset(value) | number | No | Starting number for an ordered list. |
.border(value) | number | No | Optional border thickness. |
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<{
border?: number;
elements: JsonObject[];
indent?: number;
offset?: number;
style: "bullet" | "ordered";
}, JsonObject>
RichTextQuote()
function RichTextQuote(): FluentBuilder<RichTextLayoutBuilderInput, JsonObject>;
Creates a rich-text quotation rendered with a vertical bar beside its content. Add structured rich-text elements in display order and optionally configure the surrounding border.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#rich_text_quote.
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 |
|---|---|---|---|
.elements(...values) | | Yes | Rich-text elements displayed inside the layout. |
.border(value) | number | No | Optional border width. |
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<RichTextLayoutBuilderInput, JsonObject>
RichTextSection()
function RichTextSection(): FluentBuilder<{
elements: JsonObject[];
}, JsonObject>;
Creates the basic paragraph-like container for structured rich-text elements.
Add text runs, links, emoji, and mentions with elements() before placing the
section in a rich-text block or higher-level rich-text layout.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#rich_text_section.
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 |
|---|---|---|---|
.elements(...values) | | Yes | — |
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<{
elements: JsonObject[];
}, JsonObject>
RichTextStyle
Inline formatting supported by rich-text text, links, users, and channels.
Properties
RichTextUser()
function RichTextUser(): FluentBuilder<RichTextMentionBuilderInput, JsonObject>;
Creates a structured rich-text mention for one Slack user. Slack resolves the supplied user ID to the appropriate display name when rendering the containing rich-text block.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#user-element-type.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.id(value) | string | Yes | Slack channel, user, or user-group identifier. |
.style(value) | | No | Optional Slack rich-text styling. |
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<RichTextMentionBuilderInput, JsonObject>
RichTextUserGroup()
function RichTextUserGroup(): FluentBuilder<RichTextMentionBuilderInput, JsonObject>;
Creates a structured rich-text mention for a Slack user group. Slack resolves the supplied user-group ID when rendering the containing rich-text block.
See: https://docs.slack.dev/reference/block-kit/blocks/rich-text-block#usergroup-element-type.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.id(value) | string | Yes | Slack channel, user, or user-group identifier. |
.style(value) | | No | Optional Slack rich-text styling. |
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<RichTextMentionBuilderInput, JsonObject>
SlackFile()
function SlackFile(): FluentBuilder<{
id?: string;
url?: string;
}, JsonObject>;
Creates a Slack-hosted image reference for an image block or image element. Supply exactly one Slack file ID or Slack-hosted file URL; the two source forms are mutually exclusive.
See: https://docs.slack.dev/reference/block-kit/composition-objects/slack-file-object.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.id(value) | string | No | Slack file identifier matching ^F[A-Z0-9]{8,}$, such as F0123ABC456. |
.url(value) | string | No | Slack-hosted file URL. |
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<{
id?: string;
url?: string;
}, JsonObject>
SlackIcon()
function SlackIcon(): FluentBuilder<{
name: SlackIconName;
}, SlackObject<"icon">>;
Creates a named icon supplied and rendered by Slack for use in a card block. Choose one of the supported SlackIconName values instead of supplying an image URL.
See: https://docs.slack.dev/reference/block-kit/blocks/card-block.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.name(value) | | Yes | — |
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<{
name: SlackIconName;
}, SlackObject<"icon">>
SlackIconName
type SlackIconName =
| "archive"
| "book"
| "bookmark"
| "bot"
| "bug"
| "calendar"
| "call"
| "caret-left"
| "caret-right"
| "check"
| "clipboard"
| "code"
| "comment"
| "compass"
| "copy"
| "cube"
| "download"
| "edit"
| "email"
| "eye-closed"
| "eye-open"
| "file"
| "flag"
| "folder"
| "gear"
| "globe"
| "heart"
| "help"
| "image"
| "info"
| "key"
| "lightbulb"
| "link"
| "map"
| "mobile"
| "new-window"
| "pin"
| "plus"
| "refine"
| "refresh"
| "rocket"
| "save"
| "screen"
| "share"
| "sparkle"
| "star"
| "star-filled"
| "tag"
| "thumbs-down"
| "thumbs-up"
| "trash"
| "upload"
| "user"
| "warning";
Slack-provided icon name accepted by slackIcon.
TextLike
type TextLike = string | TextObject;
Text accepted by factories: a string or an existing Slack text object.
TextObject
type TextObject = SlackObject<"plain_text" | "mrkdwn">;
A Slack plain-text or mrkdwn composition object.
Trigger()
function Trigger(): FluentBuilder<{
customizableInputParameters?: JsonObject[];
url: string;
}, JsonObject>;
Creates the link-trigger definition nested inside a workflow object. Supply the trigger URL generated by Slack and optionally add customizable input parameters.
See: https://docs.slack.dev/reference/block-kit/composition-objects/workflow-object.
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 |
|---|---|---|---|
.url(value) | string | Yes | Slack workflow trigger URL. |
.customizableInputParameters(...values) | | No | Optional parameters created with InputParameter(). |
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<{
customizableInputParameters?: JsonObject[];
url: string;
}, JsonObject>
Workflow()
function Workflow(): FluentBuilder<{
trigger: JsonObject;
}, JsonObject>;
Creates a workflow composition object for a workflow button. It wraps a trigger built with Trigger, including any customizable values the application wants to pass when the user launches the workflow.
See: https://docs.slack.dev/reference/block-kit/composition-objects/workflow-object.
Chainable setters
Call these setters in any order before .build(). Repeating a singular setter replaces its previous value.
| Setter | Value type | Required | Description |
|---|---|---|---|
.trigger(value) | | Yes | Trigger created with Trigger(). |
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<{
trigger: JsonObject;
}, JsonObject>