Slash Commands

Slash commands are Discord’s modern, native command system. They provide auto-complete, built-in argument validation, and a clean interface that’s discoverable by users. No more remembering prefixes or command syntax!

What Are Slash Commands?

Slash commands appear in Discord’s command picker when users type /. They offer:

• Auto-discovery - Users can see all available commands
• Type validation - Discord enforces argument types
• Better UX - Clean interface with descriptions and hints
• No prefix confusion - Always start with /

Command Structure

Slash commands can have three levels of organization:

1. Root Command - The base command (e.g., /level)
2. Command Group - Optional grouping (e.g., /admin settings)
3. Subcommand - Commands within a group (e.g., /admin settings view)

Simple Command Example

/level user:@John

• Root command: level
• Argument: user (type: User)

Grouped Command Example

/snippets search query:example

• Root command: snippets
• Subcommand: search
• Argument: query (type: String)

Creating a Basic Slash Command

Define slash commands in your bot’s on ready section:

Simple Command

define bot XXX:
    on ready:
        # Create command
        set {_cmd} to new slash command named "ping" with description "Check the bot's latency"

        # Register globally
        update {_cmd} globally in event-bot

Why on ready?

Register slash commands in on ready so they’re only created once when the bot starts, not every time the script reloads.

Handling the Command

on slash command:
    if event-string is "ping":
        reply with "Pong! 🏓"

The event-string contains the command name, so you can handle multiple commands in one event.

Adding Arguments (Options)

Arguments (called “options” in Discord) let users provide input to commands:

Command with Argument

on ready:
    # Create command
    set {_level} to new slash command named "level" with description "Check a user's level"

    # Add user option (optional)
    add new user option named "target" with description "The user to check" to options of {_level}

    # Register
    update {_level} globally in event-bot

on slash command:
    if event-string is "level":
        # Get the argument (might be null)
        set {_target} to argument "target" as user

        # Use fallback if not provided
        if {_target} is not set:
            set {_target} to event-user

        reply with "%mention tag of {_target}% is level 42"

Caution

Optional arguments can be null. Always provide a fallback value or check if they’re set.

Required Arguments

Make arguments mandatory:

on ready:
    set {_cmd} to new slash command named "ban" with description "Ban a user"

    # Add required user argument
    set {_option} to new user option named "user" with description "User to ban"
    set required state of {_option} to true
    add {_option} to options of {_cmd}

    update {_cmd} globally in event-bot

on slash command:
    if event-string is "ban":
        set {_user} to argument "user" as user
        # {_user} is guaranteed to be set (required)
        reply with "Banned %mention tag of {_user}%"

Option Types

Discord supports various argument types:

Type	Description	Supports Choices
STRING	Plain text	✅ Yes
INTEGER	Whole numbers	✅ Yes
NUMBER	Decimal numbers	✅ Yes
BOOLEAN	True/False	❌ No
USER	Discord user	❌ No
CHANNEL	Guild channel	❌ No
ROLE	Server role	❌ No
ATTACHMENT	File upload	❌ No

Creating Different Option Types

String

add new string option named "text" with description "Enter some text" to options of {_cmd}

# Get value
on slash command:
    set {_text} to argument "text" as string

Integer

add new integer option named "amount" with description "Enter a number" to options of {_cmd}

# Get value
on slash command:
    set {_amount} to argument "amount" as integer

Number

add new number option named "price" with description "Enter a price" to options of {_cmd}

# Get value
on slash command:
    set {_price} to argument "price" as number

Boolean

add new boolean option named "enabled" with description "Enable or disable" to options of {_cmd}

# Get value
on slash command:
    set {_enabled} to argument "enabled" as boolean
    if {_enabled} is true:
        reply with "Enabled!"

User

add new user option named "target" with description "Select a user" to options of {_cmd}

# Get value
on slash command:
    set {_user} to argument "target" as user

Channel

add new channel option named "destination" with description "Select a channel" to options of {_cmd}

# Get value
on slash command:
    set {_channel} to argument "destination" as channel

Role

add new role option named "role" with description "Select a role" to options of {_cmd}

# Get value
on slash command:
    set {_role} to argument "role" as role

Attachment

add new attachment option named "file" with description "Upload a file" to options of {_cmd}

# Get value and use it
on slash command:
    set {_file} to argument "file" as attachment

    # Check if it's an image
    if attachment {_file} is an image:
        download {_file} to path "uploads/%file name of {_file}%"
        reply with "Image saved: %file name of {_file}%"
    else:
        reply with "Please upload an image!"

Choices (Predefined Values)

For STRING, INTEGER, and NUMBER options, you can provide predefined choices:

on ready:
    set {_cmd} to new slash command named "gamemode" with description "Change your gamemode"

    # Create option with choices
    set {_option} to new string option named "mode" with description "Select gamemode"

    # Add choices
    add new choice named "Survival" with value "survival" to choices of {_option}
    add new choice named "Creative" with value "creative" to choices of {_option}
    add new choice named "Adventure" with value "adventure" to choices of {_option}
    add new choice named "Spectator" with value "spectator" to choices of {_option}

    set required state of {_option} to true
    add {_option} to options of {_cmd}

    update {_cmd} globally in event-bot

on slash command:
    if event-string is "gamemode":
        set {_mode} to argument "mode" as string

        # {_mode} is guaranteed to be one of the choice values
        reply with "Gamemode set to: %{_mode}%"

Tip

Choices create a dropdown menu in Discord. The user can only select from the provided options, ensuring valid input.

Localizations

Since DiSky v4.3.0, you can provide translations for different languages:

on ready:
    # Create command with default English name/description
    set {_cmd} to new slash command named "level" with description "Check your level"

    # Add French localization
    add new locale data for "FR" with value "niveau" to name localizations of {_cmd}
    add new locale data for "FR" with value "Voir votre niveau" to description localizations of {_cmd}

    # Add Spanish localization
    add new locale data for "ES" with value "nivel" to name localizations of {_cmd}
    add new locale data for "ES" with value "Ver tu nivel" to description localizations of {_cmd}

    update {_cmd} globally in event-bot

Users see the command in their Discord language if you’ve provided a localization.

Find locale codes in the Discord documentation.

Command Registration Scopes

You can register commands globally or per-guild:

Global Commands

# Register for all servers (takes up to 1 hour to update)
update {_cmd} globally in event-bot

Global commands:

• Available in all servers
• Take up to 1 hour to update
• Good for stable, production commands

Guild Commands

# Register for specific guild (instant update)
update {_cmd} in event-guild with event-bot

Guild commands:

• Only available in that server
• Update instantly
• Good for testing and server-specific commands

Development Tip

Use guild commands during development for instant updates, then switch to global commands for production.

Practical Examples

User Info Command

on ready:
    set {_cmd} to new slash command named "userinfo" with description "Get information about a user"

    add new user option named "target" with description "User to check (defaults to you)" to options of {_cmd}

    update {_cmd} globally in event-bot

on slash command:
    if event-string is "userinfo":
        set {_target} to argument "target" as user
        if {_target} is not set:
            set {_target} to event-user

        make embed:
            set title of embed to "User Information"
            set author of embed to discord name of {_target}
            set author icon of embed to avatar of {_target}
            set embed color of embed to blue

            add field named "ID" with value discord id of {_target} to fields of embed
            add field named "Created" with value "%creation date of {_target}%" to fields of embed

            set thumbnail of embed to avatar of {_target}

        reply with last embed

Math Command with Choices

on ready:
    set {_cmd} to new slash command named "math" with description "Perform math operations"

    # Operation choice
    set {_op} to new string option named "operation" with description "Select operation"
    add new choice named "Add" with value "add" to choices of {_op}
    add new choice named "Subtract" with value "sub" to choices of {_op}
    add new choice named "Multiply" with value "mul" to choices of {_op}
    add new choice named "Divide" with value "div" to choices of {_op}
    set required state of {_op} to true
    add {_op} to options of {_cmd}

    # Numbers
    set {_num1} to new number option named "first" with description "First number"
    set required state of {_num1} to true
    add {_num1} to options of {_cmd}

    set {_num2} to new number option named "second" with description "Second number"
    set required state of {_num2} to true
    add {_num2} to options of {_cmd}

    update {_cmd} globally in event-bot

on slash command:
    if event-string is "math":
        set {_op} to argument "operation" as string
        set {_a} to argument "first" as number
        set {_b} to argument "second" as number

        if {_op} is "add":
            set {_result} to {_a} + {_b}
        else if {_op} is "sub":
            set {_result} to {_a} - {_b}
        else if {_op} is "mul":
            set {_result} to {_a} * {_b}
        else if {_op} is "div":
            if {_b} is 0:
                reply with "❌ Cannot divide by zero!"
                stop
            set {_result} to {_a} / {_b}

        reply with "**Result:** %{_result}%"

Moderation Command with Permissions

on ready:
    set {_cmd} to new slash command named "kick" with description "Kick a user from the server"

    set {_user} to new user option named "user" with description "User to kick"
    set required state of {_user} to true
    add {_user} to options of {_cmd}

    add new string option named "reason" with description "Reason for kick" to options of {_cmd}

    update {_cmd} globally in event-bot

on slash command:
    if event-string is "kick":
        # Check permissions
        if event-user doesn't have permission "KICK_MEMBERS":
            reply with hidden "❌ You don't have permission to kick members!"
            stop

        set {_target} to argument "user" as user
        set {_reason} to argument "reason" as string
        if {_reason} is not set:
            set {_reason} to "No reason provided"

        # Perform kick
        kick {_target} from event-guild due to {_reason}

        reply with "✅ Kicked %mention tag of {_target}% - Reason: %{_reason}%"

File Upload Handler

on ready:
    set {_cmd} to new slash command named "upload" with description "Upload a file"

    set {_file} to new attachment option named "file" with description "File to upload"
    set required state of {_file} to true
    add {_file} to options of {_cmd}

    update {_cmd} globally in event-bot

on slash command:
    if event-string is "upload":
        set {_file} to argument "file" as attachment

        # Check size (8MB limit for most servers)
        if size of {_file} > 8388608:  # 8MB in bytes
            reply with hidden "❌ File too large! Maximum size is 8MB."
            stop

        # Check type
        if attachment {_file} is an image:
            download {_file} to path "uploads/images/%file name of {_file}%"
            reply with "✅ Image saved: %file name of {_file}%"
        else:
            reply with "❌ Please upload an image file!"

Admin Command Group

on ready:
    # Root command
    set {_admin} to new slash command named "admin" with description "Administration commands"

    # Create subcommand group
    set {_group} to new command group named "settings" with description "Server settings"

    # Subcommand within group
    set {_sub} to new subcommand named "view" with description "View current settings"
    add {_sub} to subcommands of {_group}

    # Add group to root command
    add {_group} to groups of {_admin}

    update {_admin} globally in event-bot

on slash command:
    if event-string is "admin":
        # Handle subcommand
        reply with "Admin settings viewed!"

Best Practices

1. Clear Descriptions

   Write helpful descriptions for commands and options. Users rely on these!

2. Use Appropriate Types

   Choose the right option type - don’t use STRING for numbers or users.

3. Provide Defaults

   For optional arguments, have sensible fallback values.

4. Validate Input

   Even with type checking, validate ranges, permissions, etc.

5. Use Choices When Appropriate

   If there are only a few valid values, use choices instead of free text.

6. Handle Edge Cases

   Check for null values, zero division, invalid permissions, etc.

7. Give Feedback

   Always reply to slash commands - users need confirmation.

Argument Naming Best Practices

Using Hyphens in Argument Names

Since DiSky v4.27, you can use hyphens (-) in argument names for improved readability:

on ready:
    set {_cmd} to new slash command named "settings" with description "Manage settings"

    # ✅ Good: Using hyphens for multi-word arguments (v4.27+)
    add new boolean option named "auto-delete" with description "Enable auto-delete" to options of {_cmd}
    add new integer option named "max-count" with description "Maximum count" to options of {_cmd}
    add new string option named "user-name" with description "User name" to options of {_cmd}

    # Also valid: Using underscores or camelCase
    add new boolean option named "auto_delete" with description "Enable auto-delete" to options of {_cmd}
    add new integer option named "maxCount" with description "Maximum count" to options of {_cmd}

    update {_cmd} globally in event-bot

on slash command:
    if event-string is "settings":
        # Access arguments using the same name
        set {_autoDelete} to argument "auto-delete" as boolean
        set {_maxCount} to argument "max-count" as integer
        set {_userName} to argument "user-name" as string

        reply with "Settings updated!"

Readability First

Hyphens often make argument names more readable than underscores or camelCase, especially for users who see them in Discord’s interface. Choose the style that works best for your bot’s consistency.

Example - Consistent Naming:

on ready:
    set {_cmd} to new slash command named "user-profile" with description "View user profile"

    set {_userOpt} to new user option named "target-user" with description "User to check"
    add {_userOpt} to options of {_cmd}

    set {_showOpt} to new boolean option named "show-badges" with description "Display badges"
    add {_showOpt} to options of {_cmd}

    set {_includeOpt} to new boolean option named "include-stats" with description "Include statistics"
    add {_includeOpt} to options of {_cmd}

    update {_cmd} globally in event-bot

Command Limits

• Command name: 1-32 characters, alphanumeric and hyphens only
• Description: 1-100 characters
• Options per command: 25 maximum
• Option names: 1-32 characters, alphanumeric, hyphens, and underscores (hyphens supported since v4.27)
• Choices per option: 25 maximum
• Subcommands per group: 25 maximum
• Groups per command: 25 maximum

Troubleshooting

Command Not Appearing

Problem: Slash command doesn’t show up in Discord.

Solutions:

• Wait up to 1 hour for global commands
• Use guild commands for instant testing
• Verify bot has applications.commands scope
• Check console for registration errors

Arguments Not Working

Problem: Can’t get argument values.

Solutions:

• Verify argument name matches exactly
• Check you’re using correct type (as user, as string, etc.)
• Ensure optional arguments are checked for null
• Make required arguments truly required

Permission Errors

Problem: Users can use commands they shouldn’t.

Solutions:

• Check permissions in your event handler
• Use Discord’s built-in permission system
• Provide clear error messages for denied access
• Log permission violations

”This interaction failed”

Problem: Discord shows error message.

Solutions:

• Reply within 3 seconds
• Use defer if processing takes time
• Check for errors in your handler
• Ensure event handler is running

Next Steps

• Add Cooldowns to prevent spam
• Learn about Modals for complex input
• Create Buttons and Dropdowns
• Understand Interactions Overview
• Explore Error Handling