Slack Skill

Slack Skill

Comprehensive Slack workspace integration with 30+ tools for messaging, channel management, user operations, reactions, pins, and more. Built with the Skill Engine SDK showcasing OAuth2 token-based authentication and the Slack Web API.

Overview

This skill provides full access to Slack's Web API, enabling automation of workspace communication and management tasks. It demonstrates type-safe parameter validation, structured error handling, and production-ready API integration patterns.

When to Use This Skill

Use this skill when you need to:

• Send messages to channels or direct messages to users
• Create, manage, and archive channels
• List and search workspace users and channels
• Add reactions and pin important messages
• Schedule messages for later delivery
• Manage threads and conversations
• Upload files and snippets
• Set user status and presence
• Search message history
• Automate Slack workflows

Prerequisites

1. Slack Workspace: Admin or appropriate permissions
2. Slack App: Create an app at api.slack.com/apps
3. Bot Token: OAuth token with required scopes

Setting Up Your Slack App

1. Go to https://api.slack.com/apps
2. Click "Create New App" → "From scratch"
3. Name your app (e.g., "Skill Engine Bot") and select your workspace
4. Navigate to "OAuth & Permissions"
5. Add Bot Token Scopes:

   Required Scopes:
   - chat:write           (Send messages)
   - channels:read        (List public channels)
   - users:read           (List users)
   - reactions:write      (Add/remove reactions)
   - pins:write           (Pin messages)
   - channels:manage      (Create/archive channels)
   - groups:write         (Manage private channels)
   - im:write             (Send DMs)
   - mpim:write           (Manage group DMs)
   - search:read          (Search messages - optional)
   - users:write          (Set status - optional)
   - files:write          (Upload files - optional)
   

6. Click "Install to Workspace" and authorize
7. Copy the "Bot User OAuth Token" (starts with xoxb-)

Configuration

Set the Slack token as an environment variable:

export SKILL_SLACK_TOKEN=xoxb-your-token-here

Or add to .skill-engine.toml:

[skills.slack-skill.instances.default]
config.slack_token = "${SLACK_TOKEN}"

Tools

Messaging Tools (4 tools)

send-message

Send a message to a Slack channel.

Examples:

# Send to channel
skill run slack-skill send-message channel=general text="Hello team!"

# Send with markdown
skill run slack-skill send-message channel=dev text="*Important:* New release deployed :rocket:"

# Reply in thread
skill run slack-skill send-message channel=general text="Follow-up message" thread_ts=1234567890.123456

send-dm

Send a direct message to a user.

Examples:

# Send DM by username
skill run slack-skill send-dm user=@john text="Hey, can you review PR #42?"

# Send DM by user ID
skill run slack-skill send-dm user=U12345ABC text="Meeting in 10 minutes"

update-message

Update an existing message.

Example:

skill run slack-skill update-message channel=C123ABC ts=1234567890.123456 text="Updated: Meeting at 3pm"

delete-message

Delete a message.

Example:

skill run slack-skill delete-message channel=C123ABC ts=1234567890.123456

schedule-message

Schedule a message for later delivery.

Example:

# Schedule message for tomorrow at 9am (Unix timestamp)
skill run slack-skill schedule-message channel=general text="Daily standup reminder" post_at=1704283200

get-thread-replies

Get all replies in a thread.

Example:

skill run slack-skill get-thread-replies channel=C123ABC ts=1234567890.123456 limit=100

Channel Tools (6 tools)

list-channels

List channels in the workspace.

Examples:

# List public channels
skill run slack-skill list-channels

# List all channels (public + private)
skill run slack-skill list-channels type=all limit=100

# List only private channels
skill run slack-skill list-channels type=private

get-channel-info

Get detailed information about a channel.

Example:

skill run slack-skill get-channel-info channel=general
skill run slack-skill get-channel-info channel=C123ABC

create-channel

Create a new channel.

Examples:

# Create public channel
skill run slack-skill create-channel name=project-alpha

# Create private channel
skill run slack-skill create-channel name=leadership is_private=true

archive-channel

Archive a channel (make it read-only).

Example:

skill run slack-skill archive-channel channel=C123ABC

invite-to-channel

Invite users to a channel.

Example:

skill run slack-skill invite-to-channel channel=C123ABC users=U111,U222,U333

kick-from-channel

Remove a user from a channel.

Example:

skill run slack-skill kick-from-channel channel=C123ABC user=U12345

set-topic

Set the topic for a channel.

Example:

skill run slack-skill set-topic channel=C123ABC topic="Q1 2024 Planning"

set-purpose

Set the purpose/description for a channel.

Example:

skill run slack-skill set-purpose channel=C123ABC purpose="Discuss project alpha milestones"

User Tools (4 tools)

list-users

List users in the workspace.

Examples:

# List human users
skill run slack-skill list-users

# Include bots
skill run slack-skill list-users include_bots=true limit=100

get-user-info

Get information about a specific user.

Examples:

skill run slack-skill get-user-info user=@john
skill run slack-skill get-user-info user=U12345ABC

get-presence

Get a user's presence status (active/away).

Example:

skill run slack-skill get-presence user=U12345ABC

set-status

Set your own status (emoji and text).

Examples:

# Simple status
skill run slack-skill set-status status_text="In a meeting"

# Status with emoji
skill run slack-skill set-status status_text="On vacation" status_emoji=":palm_tree:"

# Status that expires in 1 hour
skill run slack-skill set-status status_text="Do not disturb" status_emoji=":no_entry_sign:" expiration=1704290400

Reaction Tools (2 tools)

react

Add a reaction emoji to a message.

Examples:

skill run slack-skill react channel=C123ABC ts=1234567890.123456 emoji=thumbsup
skill run slack-skill react channel=C123ABC ts=1234567890.123456 emoji=rocket
skill run slack-skill react channel=C123ABC ts=1234567890.123456 emoji=heart

unreact

Remove a reaction from a message.

Example:

skill run slack-skill unreact channel=C123ABC ts=1234567890.123456 emoji=thumbsup

Pin Tools (2 tools)

pin-message

Pin a message to a channel.

Example:

skill run slack-skill pin-message channel=C123ABC ts=1234567890.123456

unpin-message

Unpin a message from a channel.

Example:

skill run slack-skill unpin-message channel=C123ABC ts=1234567890.123456

Search & Files (2 tools)

search-messages

Search for messages across the workspace (requires search:read scope).

Examples:

# Search for messages
skill run slack-skill search-messages query="deployment failed"

# Search with more results
skill run slack-skill search-messages query="bug" count=50 sort=timestamp

upload-file

Upload content as a file (text snippets, code).

Examples:

# Upload code snippet
skill run slack-skill upload-file \
  channels=C123ABC \
  content="console.log('Hello');" \
  filename=test.js \
  filetype=javascript \
  title="Test Script"

# Upload with comment
skill run slack-skill upload-file \
  channels=C123ABC,C456DEF \
  content="API logs from server..." \
  filename=logs.txt \
  filetype=text \
  initial_comment="Here are today's logs"

Utility Tools (1 tool)

test-connection

Test the Slack API connection and verify token.

Parameters: None

Example:

skill run slack-skill test-connection
# Output: Connected to Slack!
#         Team: My Workspace
#         Bot User: skill-engine-bot

Workflows

Daily Standup Automation

# Send standup reminder
skill run slack-skill send-message \
  channel=engineering \
  text=":wave: Good morning! Time for standup. Please share:\n1. What you did yesterday\n2. What you'll do today\n3. Any blockers?"

# React to responses
skill run slack-skill react channel=C123ABC ts=1234567890.123456 emoji=white_check_mark

Channel Management Workflow

# Create project channel
skill run slack-skill create-channel name=project-phoenix

# Set topic and purpose
skill run slack-skill set-topic channel=C123ABC topic="Project Phoenix - Q1 2024"
skill run slack-skill set-purpose channel=C123ABC purpose="Coordinate Project Phoenix development"

# Invite team members
skill run slack-skill invite-to-channel channel=C123ABC users=U111,U222,U333

# Send welcome message
skill run slack-skill send-message channel=project-phoenix text="Welcome to Project Phoenix! :rocket:"

Notification & Alert Workflow

# Send alert to channel
skill run slack-skill send-message \
  channel=alerts \
  text=":rotating_light: *ALERT:* Database CPU usage >90%\nServer: prod-db-01\nTime: $(date)"

# Send DM to on-call engineer
skill run slack-skill send-dm \
  user=@oncall \
  text="FYI: Alert triggered for database. Check #alerts channel."

# Pin critical message
skill run slack-skill pin-message channel=C123ABC ts=1234567890.123456

Status Update Workflow

# Set away status
skill run slack-skill set-status \
  status_text="Lunch break" \
  status_emoji=":fork_and_knife:" \
  expiration=$(date -d '+1 hour' +%s)

# Update channel topic with current sprint
skill run slack-skill set-topic \
  channel=C123ABC \
  topic="Sprint 42 (Jan 2-15) | Goal: Launch beta | Daily standup @9am"

Error Handling

The skill provides clear error messages for common issues:

Rate Limits

Slack API has tiered rate limits:

• Tier 1 (most endpoints): 1 request per second
• Tier 2 (chat.postMessage): 1 request per second per channel
• Tier 3 (search, files): Lower limits
• Tier 4 (special methods): Higher limits

The skill handles rate limit errors and includes retry information.

Security Notes

• Token Security: Store tokens in environment variables, never in code
• Scope Minimization: Only request scopes your bot needs
• Channel Access: Bot can only access public channels and private channels it's invited to
• User Privacy: Cannot read DMs between users (only bot's own DMs)
• Audit Logs: Slack maintains audit logs of all bot actions

Best Practices

1. Use Channel Names When Possible: More readable than IDs in scripts
2. Check Responses: Slack returns ok: false for API errors even with 200 status
3. Thread Conversations: Use thread_ts to keep related messages together
4. Format Messages: Use Slack's markdown for better readability
5. Test in Private Channels: Test bots in private channels before public use
6. Monitor Rate Limits: Check X-Rate-Limit-* headers in responses
7. Handle Errors Gracefully: Retry on rate limits, fail clearly on auth errors

Slack Markdown Reference

*bold text*
_italic text_
~strikethrough~
`code`
```code block```
> quote
• bulleted list
1. numbered list
<URL|link text>
<@U12345> (mention user)
<#C12345> (link to channel)
:emoji: (emoji by name)

Troubleshooting

Bot Not Receiving Permissions

# Verify scopes in Slack app settings
# Reinstall app to workspace
# Test connection
skill run slack-skill test-connection

Cannot Find Channel

# List all channels bot can see
skill run slack-skill list-channels type=all

# Check if bot is invited to private channel
# Invite bot via Slack UI: /invite @your-bot-name

Messages Not Sending

# Verify token is set
echo $SKILL_SLACK_TOKEN

# Test connection
skill run slack-skill test-connection

# Check channel name (without #)
skill run slack-skill send-message channel=general text="Test"  # Correct
skill run slack-skill send-message channel=#general text="Test" # May fail

SDK Features Demonstrated

This skill showcases advanced SDK patterns:

1. Authenticated HTTP Client

const client = createAuthenticatedClient({
  baseUrl: 'https://slack.com/api',
  authType: 'bearer',
  tokenKey: 'SLACK_TOKEN',
});

2. Error Handling with Context

if (response.status === 429) {
  return err('Rate limit exceeded', errors.rateLimit());
}

3. Parameter Validation

{
  name: 'channel',
  paramType: 'string',
  validation: {
    minLength: 1,
    maxLength: 80,
  },
}

4. Enum Validation

{
  name: 'type',
  paramType: 'string',
  validation: {
    enum: ['public', 'private', 'all'],
  },
}

Resources

• Slack API Documentation
• Slack Bot Users
• Slack App Management
• OAuth Scopes Reference
• Slack Markdown Formatting
• Rate Limits

Contributing

Contributions welcome! Possible enhancements:

• Slash command support
• Interactive message components
• Event subscriptions
• File download support
• Workflow builder integration
• Enterprise Grid features