Slack

Usage

slack is a CLI on $PATH. Call it directly, for example:

slack user list

Bash command rules

1. No # in commands. Use general not #general. No # comments; use the Bash tool description field instead.
2. No '' or "". Avoid patterns like d.get('key', '').
3. Only | jq for filtering. No python3 -c or other pipes. Use single-quoted jq expressions only.
4. No || or &&. Run separate commands in separate Bash tool calls.
5. No > or >>. Consume JSON output directly.

Messages and threads

Fetch a single message (with thread summary):

slack message get "https://workspace.slack.com/archives/C123/p1700000000000000"

Fetch the full thread:

slack message list "https://workspace.slack.com/archives/C123/p1700000000000000"

Browse recent channel messages:

slack message list "general" --limit 20
slack message list "C0123ABC" --limit 10
slack message list "general" --with-reaction eyes --oldest "1770165109.000000" --limit 20
slack message list "general" --without-reaction dart --oldest "1770165109.000000" --limit 20

message get/list and search auto-download attachments and include absolute file paths in JSON (for example message.files[].path, files[].path).

Draft and send messages

Open a browser-based rich-text editor:

slack message draft "general"
slack message draft "general" "initial text"
slack message draft "https://workspace.slack.com/archives/C123/p1700000000000000"

Send, edit, delete, react:

slack message send "https://workspace.slack.com/archives/C123/p1700000000000000" "I can take this."
slack message send "alerts-staging" "here's the report" --attach ./report.md
slack message edit "https://workspace.slack.com/archives/C123/p1700000000000000" "I can take this today."
slack message delete "https://workspace.slack.com/archives/C123/p1700000000000000"

slack message send "general" "Here's the plan:
- Step 1: do the thing
- Step 2: verify it worked
  - Sub-step: check logs"
slack message react add "https://workspace.slack.com/archives/C123/p1700000000000000" "eyes"
slack message react remove "https://workspace.slack.com/archives/C123/p1700000000000000" "eyes"

Channel mode edit/delete (requires --ts):

slack message edit "general" "Updated text" --workspace "myteam" --ts "1770165109.628379"
slack message delete "general" --workspace "myteam" --ts "1770165109.628379"

Attachments for message send:

• --attach <path> upload a local file (repeatable).

Channels and invites

The --limit flag controls the scan range. Use a high value to cover large workspaces:

slack channel list --all --limit 500

Use channel IDs when known:

slack message list "C0123ABC" --limit 10

Channel operations:

slack channel list
slack channel list --user "@alice" --limit 50
slack channel list --all --limit 500
slack channel new --name "incident-war-room"
slack channel new --name "incident-leads" --private
slack channel invite --channel "incident-war-room" --users "U01AAAA,@alice,bob@example.com"
slack channel invite --channel "incident-war-room" --users "partner@vendor.com" --external
slack channel invite --channel "incident-war-room" --users "partner@vendor.com" --external --allow-external-user-invites

For --external, invite targets must be emails. --allow-external-user-invites lets them invite others.

Search (messages and files)

Prefer channel-scoped search:

slack search all "smoke tests failed" --channel "alerts" --after 2026-01-01 --before 2026-02-01
slack search messages "stably test" --user "@alice" --channel general
slack search files "testing" --content-type snippet --limit 10

Multiple workspaces

When using channel names with multiple workspaces, pass --workspace or set SLACK_WORKSPACE_URL:

slack message get "general" --workspace "https://myteam.slack.com" --ts "1770165109.628379"
slack message get "general" --workspace "myteam" --ts "1770165109.628379"

DM and group DM

Open a DM or group DM and get its channel ID:

slack user dm-open @alice @bob
slack user dm-open U01AAAA U02BBBB U03CCCC

Mark as read

Mark read up to a message:

slack channel mark "https://workspace.slack.com/archives/C123/p1700000000000000"
slack channel mark "general" --workspace "myteam" --ts "1770165109.628379"
slack channel mark "D0A04PB2QBW" --workspace "myteam" --ts "1770165109.628379"

Make a specific message appear unread by setting --ts just before it:

slack channel mark "general" --workspace "myteam" --ts "1770165109.628378"

Canvas and users

slack canvas get "https://workspace.slack.com/docs/T123/F456"
slack user list --workspace "https://workspace.slack.com" --limit 100
slack user get "@alice" --workspace "https://workspace.slack.com"

References

• references/commands.md: command map and flags
• references/targets.md: URL vs channel targeting rules
• references/output.md: JSON shapes and download paths