mattermost-cli
A CLI for Mattermost that outputs JSON by default, designed for both human use and agent automation. Runs against any Mattermost server with personal access tokens or password+MFA auth.
Install
# Run directly (no install)
uvx --from mattermost-cli mm --help
# Or install globally
pip install mattermost-cli
What it does
mm overview # Mentions + unread + active channels
mm messages general # Read channel messages
mm messages general --threads # Thread index (root + reply count)
mm messages @alice # Read DMs with a user
mm thread abc123def456... # Read a thread
mm search "deployment issue" # Search across all teams
mm mentions # Posts that @mention you
mm channel general # Channel info, members, pinned count
mm user @alice # Profile, status, timezone
mm pinned general # Pinned posts
mm members general # Channel members with online status
mm channels --since 6h # Recently active channels
mm unread # Channels with unread messages
Every command outputs JSON by default. Add --human for markdown.
JSON-first
Default output is structured JSON with fields designed for programmatic consumption:
{
"id": "abc123...",
"thread_id": "def456...",
"is_reply": true,
"author": "@alice",
"message": "Can you check this?",
"created_at": "2026-03-05T06:52:30Z",
"channel": "engineering",
"reply_count": 12,
"file_count": 1,
"is_bot": true,
"bot_name": "alertmatter",
"reactions": {"+1": 3, "white_check_mark": 1}
}
ISO 8601 timestamps, human-readable type labels, thread IDs on every post, bot detection, reaction counts, and file metadata included.
Agent-tuned defaults
Commands are tuned for running without flags first, then refining with --help:
mm overviewreturns mentions, unreads, and active channels in a single callmm mentionsincludes root message context on replies (so you know what "this" refers to)mm threadreturns root + last 9 replies (not the entire thread)mm unreadincludes areffield you can pass directly tomm messagesmm messages --threadsgroups by thread instead of showing flat messages- Bot posts automatically extract alert text from webhook attachments
Agent skill
Install as a coding agent skill:
npx skills add rhnvrm/mattermost-cli
Learn more
- Quickstart - Install, authenticate, first commands
- Guide
- Commands - All commands with examples
- JSON Output - Output format reference
- Authentication - Login methods and token storage
- Tips - Filtering, searching, and workflow patterns