Slack Ops

Slack Ops

Interact with Slack via the official Web API using curl. Requires a SLACK_TOKEN environment variable (Bot Token starting with xoxb-).

Prerequisites

No CLI install needed — uses curl (pre-installed on macOS/Linux).

Set up your bot token:

export SLACK_TOKEN="xoxb-your-token-here"
# Or add to ~/.zshrc / ~/.bashrc for persistence

To get a token: https://api.slack.com/apps → Create App → OAuth & Permissions → add scopes (chat:write, channels:read, reactions:write, pins:write) → Install to Workspace → copy Bot User OAuth Token.

Commands

Send a message:

curl -s -X POST https://slack.com/api/chat.postMessage \
  -H "Authorization: Bearer $SLACK_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"channel": "#general", "text": "Hello team!"}'

Send with blocks (rich text):

curl -s -X POST https://slack.com/api/chat.postMessage \
  -H "Authorization: Bearer $SLACK_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"channel": "#general", "blocks": [{"type":"section","text":{"type":"mrkdwn","text":"*Update*: Build passed."}}]}'

Add a reaction:

# Requires channel ID, message timestamp
curl -s -X POST https://slack.com/api/reactions.add \
  -H "Authorization: Bearer $SLACK_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"channel": "C12345678", "name": "white_check_mark", "timestamp": "1609459200.000100"}'

Pin a message:

curl -s -X POST https://slack.com/api/pins.add \
  -H "Authorization: Bearer $SLACK_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"channel": "C12345678", "timestamp": "1609459200.000100"}'

List channels:

curl -s "https://slack.com/api/conversations.list?limit=50" \
  -H "Authorization: Bearer $SLACK_TOKEN" | jq '.channels[] | {id, name}'

Get channel history:

curl -s "https://slack.com/api/conversations.history?channel=C12345678&limit=20" \
  -H "Authorization: Bearer $SLACK_TOKEN" | jq '.messages[] | {ts, text, user}'

Usage Examples

Post a quick status update:

curl -s -X POST https://slack.com/api/chat.postMessage \
  -H "Authorization: Bearer $SLACK_TOKEN" \
  -H "Content-Type: application/json" \
  -d '{"channel": "#deploys", "text": "v2.1.0 deployed to production."}'

Rules

• Always check that SLACK_TOKEN is set before running any command: [[ -z "$SLACK_TOKEN" ]] && echo "SLACK_TOKEN not set"
• If token is missing, instruct user to set it and stop
• Never print the token value in output
• Always parse API responses with jq and check "ok": true; if "ok": false, show the error field
• Channel names use #name format for posting; channel IDs (C...) are required for reactions/pins — run channels.list first if needed
• Confirm message sends with: "Posted to #"
• Keep messages concise; for long content, consider posting a summary with a workspace file link