Slack Assistant (slackcli)

Use the slackcli CLI (from shaharia-lab/slackcli) for Slack workspace automation: reading messages, sending messages, reactions, and canvases.

Important: This is NOT the official Slack Developer CLI (slack/slack-dev). Use the slack-cli skill for Slack app development workflows.

Default Workspaces

Use --workspace=<name-or-id> to target a specific workspace. Without --workspace, the default workspace set via slackcli auth set-default is used.

When to Use

• User asks "what's in #channel-name" or "check the Slack channel"
• User wants to send a message or reply to a thread
• User asks about Slack canvases
• User wants to add a reaction to a message
• Workspace is .slack.com (or whichever workspace the user indicates)

Authentication

# List authenticated workspaces
slackcli auth list

# Login with a bot/user token (run once per workspace)
slackcli auth login --token=<your-bot-token> --workspace-name="My Team"

# Login with browser session tokens (no Slack app needed)
slackcli auth parse-curl --login    # paste cURL from browser DevTools

# Set default workspace
slackcli auth set-default T1234567  # use workspace ID from auth list

Configuration is stored in ~/.config/slackcli/workspaces.json.

Conversation Commands

# List all channels in the default workspace
slackcli conversations list

# List channels in a specific workspace
slackcli conversations list --workspace=

# Filter by type
slackcli conversations list --types=public_channel
slackcli conversations list --types=im

# Read recent messages from a channel
slackcli conversations read C1234567890

# Read a specific thread
slackcli conversations read C1234567890 --thread-ts=1234567890.123456

# Read with limit and JSON output (includes ts/thread_ts for replies)
slackcli conversations read C1234567890 --limit=50 --json

Message Commands

# Send a message to a channel
slackcli messages send --recipient-id=C1234567890 --message="Hello team!"

# Send a DM to a user
slackcli messages send --recipient-id=U9876543210 --message="Hey there!"

# Reply to a thread
slackcli messages send --recipient-id=C1234567890 \
  --thread-ts=1234567890.123456 --message="Great idea!"

# Add an emoji reaction to a message
slackcli messages react --channel-id=C1234567890 \
  --timestamp=1234567890.123456 --emoji=+1

Common emojis: +1, heart, fire, eyes, tada, rocket, white_check_mark

Canvas Commands

# List canvases in the workspace
slackcli canvas list
slackcli canvas list --channel=C1234567890

# Read canvas content as markdown
slackcli canvas read F1234567890

# Read canvas in JSON format
slackcli canvas read F1234567890 --json

Multi-Workspace Usage

# Use workspace explicitly
slackcli conversations list --workspace=

slackcli conversations list

# Use workspace by Slack team ID
slackcli conversations list --workspace=T1234567

Workflow for Reading a Channel

1. Find the channel ID: slackcli conversations list --workspace=| grep <name>
2. Read recent messages: slackcli conversations read <channel-id> --limit=20
3. For threaded replies: use --thread-ts=<ts> from the message timestamp

Notes

• Channel IDs start with C, user IDs start with U, team IDs start with T
• Timestamps in Slack are Unix epoch with microseconds (e.g., 1234567890.123456)
• Use --json for programmatic processing; plain output is human-readable
• Browser session tokens expire with the browser session — prefer bot tokens for automation
• Run slackcli update to update to the latest release