kortix-slack

For a one-liner, post directly:

slack send "Reverted api@a3f1. Errors are back to baseline — auth header is now preserved on retry."

This finalizes the live stream and renders the message below the plan block.

slack send --blocks-file <path> — Block Kit answer (preferred for structure)

When the response has real structure — sections, headers, lists, links, citations — ship it as Block Kit. Slack accepts a closing blocks chunk on chat.stopStream, so the rich layout renders inline below the plan block. Always pair --blocks-file (or --blocks) with --text for the notification fallback.

Write the JSON to a temp file, then send:

cat > /tmp/answer.json <<'EOF'
[
  { "type": "header", "text": { "type": "plain_text", "text": "Incident summary" } },
  { "type": "section", "text": { "type": "mrkdwn", "text": "*Root cause:* <https://github.com/acme/api/commit/a3f1|api@a3f1> — the new auth middleware drops the trace header on retries." } },
  { "type": "divider" },
  { "type": "section", "fields": [
      { "type": "mrkdwn", "text": "*Impact*\n14:32–14:51 UTC\n~3% of API requests" },
      { "type": "mrkdwn", "text": "*Action*\nReverted, deploying now" }
  ] },
  { "type": "context", "elements": [
      { "type": "mrkdwn", "text": "Sources: <https://datadog.example.com/dash/api-errors|Datadog>  ·  <https://github.com/acme/api/pull/8421|Revert PR>" }
  ] }
]
EOF

slack send --text "Reverted api@a3f1 — root cause was the auth middleware" --blocks-file /tmp/answer.json

Use Block Kit when ANY of these apply:

• The answer has 2+ distinct sections (root cause + impact + action, or summary + details + sources).
• You're presenting comparisons, tables, or lists of items.
• The answer should cite multiple sources prominently.
• The response benefits from a clear title (use a header block).

Use plain slack send "..." when the answer is short prose with no structure.

Block Kit cheat sheet

Common block types the agent uses most:

Carousel of cards — for presenting a list of choices/items

When the answer is a list of things the user might pick between or browse (deploy candidates, repo search hits, scheduled meetings, design variants), a carousel of cards reads way better than a markdown list. Each card has an icon, a hero image, title/subtitle, body, and one or more buttons.

Important constraints (Slack rules, not ours):

• Cards live ONLY inside a carousel block.
• Cards support body (mrkdwn) and actions (buttons / select menus) — they do NOT support input / radio_buttons / checkboxes. If you need form inputs, use the question tool instead.
• Each card's button click fires a block_actions interaction; the platform routes it back as a follow-up Slack message (Picked: <button label>) into the same thread, the agent's next turn starts from that.
• 2–10 cards per carousel.

Example — presenting 3 deploy candidates:

[
  { "type": "section", "text": { "type": "mrkdwn", "text": "*Three deploy candidates* — pick one to ship:" } },
  {
    "type": "carousel",
    "elements": [
      {
        "type": "card",
        "block_id": "deploy_a3f1",
        "icon": { "type": "image", "image_url": "https://github.com/acme.png?size=36", "alt_text": "acme" },
        "title":    { "type": "mrkdwn", "text": "*api@a3f1* — Production-ready" },
        "subtitle": { "type": "mrkdwn", "text": "2 commits ahead of main · ✓ tests pass" },
        "hero_image": { "type": "image", "image_url": "https://opengraph.githubassets.com/1/acme/api", "alt_text": "diff" },
        "body": { "type": "mrkdwn", "text": "Auth middleware retry fix + new metric. Safe to ship — small surface area, full coverage." },
        "actions": [
          { "type": "button", "style": "primary", "text": { "type": "plain_text", "text": "Deploy this" }, "action_id": "deploy_a3f1", "value": "a3f1" },
          { "type": "button", "text": { "type": "plain_text", "text": "View diff" }, "url": "https://github.com/acme/api/compare/main...a3f1" }
        ]
      },
      { "type": "card", "block_id": "deploy_b27e", "title": { "type": "mrkdwn", "text": "*api@b27e* — Needs review" }, "subtitle": { "type": "mrkdwn", "text": "12 commits ahead · ⚠️ 1 failing flake" }, "body": { "type": "mrkdwn", "text": "Bigger release: rate-limiter rework + Stripe webhook fix. Flake is in webhook tests." }, "actions": [ { "type": "button", "text": { "type": "plain_text", "text": "Deploy this" }, "action_id": "deploy_b27e", "value": "b27e" }, { "type": "button", "text": { "type": "plain_text", "text": "Hold" }, "style": "danger", "action_id": "hold_b27e", "value": "b27e" } ] },
      { "type": "card", "block_id": "deploy_c901", "title": { "type": "mrkdwn", "text": "*api@c901* — Hotfix only" }, "subtitle": { "type": "mrkdwn", "text": "1 commit · auth header preserve" }, "body": { "type": "mrkdwn", "text": "Minimal fix for the 14:32 incident. Lowest risk." }, "actions": [ { "type": "button", "style": "primary", "text": { "type": "plain_text", "text": "Deploy this" }, "action_id": "deploy_c901", "value": "c901" } ] }
    ]
  }
]

Ship it the same way as any Block Kit answer:

slack send --text "Pick a deploy candidate" --blocks-file /tmp/candidates.json

When to reach for carousel:

• 2–6 items the user is choosing between, each with non-trivial context (subtitle, body, hero image).
• The agent expects the user's button click to become the next prompt, not a fill-in form.

When NOT to:

• For mid-turn structured input (use question instead — carousel can't host inputs).
• For 1 item (just a section) or 7+ items (split, paginate, or summarize).
• For a quick yes/no (use question with single-select).

Full Block Kit reference: https://docs.slack.dev/reference/block-kit/blocks/

Tone (applies to either mode)

Reply like a colleague messaging on Slack:

• No preamble. Don't open with "Sure!" / "I've taken a look and…". Get to the answer.
• Slack mrkdwn. *bold* (single asterisks), _italic_, `code`, ```code blocks```. Markdown-style **bold** renders as literal asterisks — don't use it.
• Short. A few sentences > a wall of text. Use bullet lists for ≥3 items.
• Link with <url|text>. Slack's syntax, not Markdown [label](url).
• No XML / no "Here's a summary:" headers. This is a chat message, not a report.

One slack send per turn

Each turn finalizes exactly one stream. Don't call slack send twice — the second call drops silently because the stream is already closed. If you need to deliver multiple things, fold them into one Block Kit message or use slack send --channel ... for sibling posts.

{
  "questions": [
    {
      "question": "Which environment should I deploy to?",
      "header": "Environment",          // short label (max 30 chars)
      "options": [
        { "value": "prod",    "label": "Production" },
        { "value": "staging", "label": "Staging" },
        { "value": "dev",     "label": "Dev (sandbox)" }
      ],
      "multiple": false,                 // false = radio, true = checkboxes
      "custom":   true                   // true = also show a free-text box
    }
  ]
}

{
  "questions": [
    {
      "question": "Priority for next sprint",
      "header":   "Priority",
      "options": [
        { "value": "auth",    "label": "Finish the auth migration" },
        { "value": "billing", "label": "Ship metered billing v2" },
        { "value": "ingest",  "label": "Rebuild the ingest pipeline" }
      ],
      "multiple": false
    },
    {
      "question": "What risks should I flag?",
      "header":   "Risks",
      "options": [
        { "value": "rollback", "label": "Rollback complexity" },
        { "value": "perf",     "label": "Performance regressions" },
        { "value": "data",     "label": "Data migrations" }
      ],
      "multiple": true
    },
    {
      "question": "Any constraints I should know about?",
      "header":   "Constraints",
      "options":  [],
      "custom":   true
    }
  ]
}

// for the 3-question example above
[
  ["auth"],                              // single-select
  ["rollback", "data"],                  // multi-select
  ["Vendor X freeze ends Tuesday."]      // custom text only
]

slack send \
  --channel "$SLACK_CHANNEL_ID" \
  --thread  "$SLACK_THREAD_TS" \
  --file    /workspace/output/report.md \
  --text    "Full report ↓"

slack send --channel "$SLACK_CHANNEL_ID" --thread "$SLACK_THREAD_TS" \
  --file /workspace/output/report.md --text "Full report attached."
slack send "Pulled 12,847 sign-ups, grouped by source. CSV above."

slack history --channel "$SLACK_CHANNEL_ID" --thread "$SLACK_THREAD_TS"
slack thread   --channel "$SLACK_CHANNEL_ID" --ts     "$SLACK_THREAD_TS"

slack react --channel "$SLACK_CHANNEL_ID" --ts "$SLACK_TRIGGER_TS" --emoji "white_check_mark"

slack send --channel "C0123ABCD" --text "Heads up: rolled api@a3f1 forward."

slack edit   --channel "$SLACK_CHANNEL_ID" --ts "<msg_ts>" --text "Updated answer."
slack delete --channel "$SLACK_CHANNEL_ID" --ts "<msg_ts>"

slack search --query "deploy api@"

slack users
slack user        --user "U0123ABCD"
slack channels
slack channel-info --channel "C0123ABCD"
slack me

slack file-info --file "F0123ABCD"
slack download  --url "<file.url_private>" --out /workspace/incoming/x.png