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Interact with Slack workspaces using browser automation. Use when the user needs to check unread channels, navigate Slack, send messages, extract data, find information, search conversations, or automate any Slack task. Triggers include "check my Slack", "what channels have unreads", "send a message to", "search Slack for", "extract from Slack", "find who said", or any task requiring programmatic Slack interaction.

Install with Tessl CLI

npx tessl i github:vercel-labs/agent-browser --skill slack
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Slack Automation

Interact with Slack workspaces to check messages, extract data, and automate common tasks.

Quick Start

Connect to an existing Slack browser session or open Slack:

# Connect to existing session on port 9222 (typical for already-open Slack)
agent-browser connect 9222

# Or open Slack if not already running
agent-browser open https://app.slack.com

Then take a snapshot to see what's available:

agent-browser snapshot -i

Core Workflow

  1. Connect/Navigate: Open or connect to Slack
  2. Snapshot: Get interactive elements with refs (@e1, @e2, etc.)
  3. Navigate: Click tabs, expand sections, or navigate to specific channels
  4. Extract/Interact: Read data or perform actions
  5. Screenshot: Capture evidence of findings
# Example: Check unread channels
agent-browser connect 9222
agent-browser snapshot -i
# Look for "More unreads" button
agent-browser click @e21  # Ref for "More unreads" button
agent-browser screenshot slack-unreads.png

Common Tasks

Checking Unread Messages

# Connect to Slack
agent-browser connect 9222

# Take snapshot to locate unreads button
agent-browser snapshot -i

# Look for:
# - "More unreads" button (usually near top of sidebar)
# - "Unreads" toggle in Activity tab (shows unread count)
# - Channel names with badges/bold text indicating unreads

# Navigate to Activity tab to see all unreads in one view
agent-browser click @e14  # Activity tab (ref may vary)
agent-browser wait 1000
agent-browser screenshot activity-unreads.png

# Or check DMs tab
agent-browser click @e13  # DMs tab
agent-browser screenshot dms.png

# Or expand "More unreads" in sidebar
agent-browser click @e21  # More unreads button
agent-browser wait 500
agent-browser screenshot expanded-unreads.png

Navigating to a Channel

# Search for channel in sidebar or by name
agent-browser snapshot -i

# Look for channel name in the list (e.g., "engineering", "product-design")
# Click on the channel treeitem ref
agent-browser click @e94  # Example: engineering channel ref
agent-browser wait --load networkidle
agent-browser screenshot channel.png

Finding Messages/Threads

# Use Slack search
agent-browser snapshot -i
agent-browser click @e5  # Search button (typical ref)
agent-browser fill @e_search "keyword"
agent-browser press Enter
agent-browser wait --load networkidle
agent-browser screenshot search-results.png

Extracting Channel Information

# Get list of all visible channels
agent-browser snapshot --json > slack-snapshot.json

# Parse for channel names and metadata
# Look for treeitem elements with level=2 (sub-channels under sections)

Checking Channel Details

# Open a channel
agent-browser click @e_channel_ref
agent-browser wait 1000

# Get channel info (members, description, etc.)
agent-browser snapshot -i
agent-browser screenshot channel-details.png

# Scroll through messages
agent-browser scroll down 500
agent-browser screenshot channel-messages.png

Taking Notes/Capturing State

When you need to document findings from Slack:

# Take annotated screenshot (shows element numbers)
agent-browser screenshot --annotate slack-state.png

# Take full-page screenshot
agent-browser screenshot --full slack-full.png

# Get current URL for reference
agent-browser get url

# Get page title
agent-browser get title

Sidebar Structure

Understanding Slack's sidebar helps you navigate efficiently:

- Threads
- Huddles
- Drafts & sent
- Directories
- [Section Headers - External connections, Starred, Channels, etc.]
  - [Channels listed as treeitems]
- Direct Messages
  - [DMs listed]
- Apps
  - [App shortcuts]
- [More unreads] button (toggles unread channels list)

Key refs to look for:

  • @e12 - Home tab (usually)
  • @e13 - DMs tab
  • @e14 - Activity tab
  • @e5 - Search button
  • @e21 - More unreads button (varies by session)

Tabs in Slack

After clicking on a channel, you'll see tabs:

  • Messages - Channel conversation
  • Files - Shared files
  • Pins - Pinned messages
  • Add canvas - Collaborative canvas
  • Other tabs depending on workspace setup

Click tab refs to switch views and get different information.

Extracting Data from Slack

Get Text Content

# Get a message or element's text
agent-browser get text @e_message_ref

Parse Accessibility Tree

# Full snapshot as JSON for programmatic parsing
agent-browser snapshot --json > output.json

# Look for:
# - Channel names (name field in treeitem)
# - Message content (in listitem/document elements)
# - User names (button elements with user info)
# - Timestamps (link elements with time info)

Count Unreads

# After expanding unreads section:
agent-browser snapshot -i | grep -c "treeitem"
# Each treeitem with a channel name in the unreads section is one unread

Best Practices

  • Connect to existing sessions: Use agent-browser connect 9222 if Slack is already open. This is faster than opening a new browser.
  • Take snapshots before clicking: Always snapshot -i to identify refs before clicking buttons.
  • Re-snapshot after navigation: After navigating to a new channel or section, take a fresh snapshot to find new refs.
  • Use JSON snapshots for parsing: When you need to extract structured data, use snapshot --json for machine-readable output.
  • Pace interactions: Add sleep 1 between rapid interactions to let the UI update.
  • Check accessibility tree: The accessibility tree shows what screen readers (and your automation) can see. If an element isn't in the snapshot, it may be hidden or require scrolling.
  • Scroll in sidebar: Use agent-browser scroll down 300 --selector ".p-sidebar" to scroll within the Slack sidebar if channel list is long.

Limitations

  • Cannot access Slack API: This uses browser automation, not the Slack API. No OAuth, webhooks, or bot tokens needed.
  • Session-specific: Screenshots and snapshots are tied to the current browser session.
  • Rate limiting: Slack may rate-limit rapid interactions. Add delays between commands if needed.
  • Workspace-specific: You interact with your own workspace -- no cross-workspace automation.

Debugging

Check console for errors

agent-browser console
agent-browser errors

View raw HTML of an element

# Snapshot shows the accessibility tree. If an element isn't there,
# it may not be interactive (e.g., div instead of button)
# Use snapshot -i -C to include cursor-interactive divs
agent-browser snapshot -i -C

Get current page state

agent-browser get url
agent-browser get title
agent-browser screenshot page-state.png

Example: Full Unread Check

#!/bin/bash

# Connect to Slack
agent-browser connect 9222

# Take initial snapshot
echo "=== Checking Slack unreads ==="
agent-browser snapshot -i > snapshot.txt

# Check Activity tab for unreads
agent-browser click @e14  # Activity tab
agent-browser wait 1000
agent-browser screenshot activity.png
ACTIVITY_RESULT=$(agent-browser get text @e_main_area)
echo "Activity: $ACTIVITY_RESULT"

# Check DMs
agent-browser click @e13  # DMs tab
agent-browser wait 1000
agent-browser screenshot dms.png

# Check unread channels in sidebar
agent-browser click @e21  # More unreads button
agent-browser wait 500
agent-browser snapshot -i > unreads-expanded.txt
agent-browser screenshot unreads.png

# Summary
echo "=== Summary ==="
echo "See activity.png, dms.png, and unreads.png for full details"

References

  • Slack docs: https://slack.com/help
  • Web experience: https://app.slack.com
  • Keyboard shortcuts: Type ? in Slack for shortcut list
Repository
github.com/vercel-labs/agent-browser
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