message/sendAndWait

When to Use

• Slack-based approvals: A manager receives a budget approval request via DM, types "approved" or "rejected", and the workflow automatically routes the request to the next step based on the reply text.
• Data validation checkpoints: An analyst receives a pipeline data summary and must confirm the numbers look correct before the workflow continues to load production data.
• Incident acknowledgement: An on-call engineer receives an alert page and must reply "ack" to prevent automatic escalation to the next responder.
• Customer confirmation: A customer-facing bot sends an order summary and awaits the customer's "confirm" reply before processing payment and fulfilling the order.
• QA sign-off gate: A test pipeline posts test results to a QA engineer and waits for "LGTM" before proceeding to the deploy stage.

Configuration

Connection

Operation

Sample Configuration

{
  "resource": "message",
  "operation": "sendAndWait",
  "botToken": "{{ $credentials.slackBotToken }}",
  "channel": "{{ $input.managerSlackUserId }}",
  "text": "Approval required for purchase order *#{{ $input.poNumber }}* — Amount: *${{ $input.amount }}*\nRequested by: {{ $input.requesterName }}\n\nReply *approved* to proceed or *rejected* to decline.",
  "timeoutSeconds": 86400,
  "blocksJson": "[{\"type\":\"section\",\"text\":{\"type\":\"mrkdwn\",\"text\":\"*Purchase Order Approval Request*\\nPO: `{{ $input.poNumber }}`\\nAmount: *${{ $input.amount }}*\\nRequester: {{ $input.requesterName }}\"}},{\"type\":\"actions\",\"elements\":[{\"type\":\"button\",\"text\":{\"type\":\"plain_text\",\"text\":\"Approve\"},\"value\":\"approved\",\"style\":\"primary\"},{\"type\":\"button\",\"text\":{\"type\":\"plain_text\",\"text\":\"Reject\"},\"value\":\"rejected\",\"style\":\"danger\"}]}]"
}

Validation Errors

Output

Waiting Port

Fires immediately after the message is sent, before any reply is received. The workflow execution is suspended at this point. Connect this port to a monitoring or audit log node to track in-flight approvals.

Success Port

Fires when a reply is received before the timeout expires. Execution resumes here with the reply content.

Error Port

Fires when the initial message send fails, when a timeout expires (if timeoutSeconds is set), or when the runtime cannot process the reply event. Always handle this port.

Sample Output

{
  "messageTs": "1716702000.045100",
  "replyText": "approved",
  "replyUserId": "U04MANAGER1",
  "replyTs": "1716705600.088300",
  "status": "ok",
  "errorCode": "",
  "payload": {
    "ok": true,
    "channel": "D04MANAGER1",
    "original_ts": "1716702000.045100",
    "reply": {
      "user": "U04MANAGER1",
      "text": "approved",
      "ts": "1716705600.088300"
    }
  }
}

Expression Reference

Node Policies & GuardRails

Examples

Purchase Order Approval via DM

{
  "resource": "message",
  "operation": "sendAndWait",
  "botToken": "{{ $credentials.slackBotToken }}",
  "channel": "{{ $output.lookupManager.userId }}",
  "text": "Approval needed for PO #{{ $input.poNumber }} — ${{ $input.amount }}. Reply *approved* or *rejected*.",
  "timeoutSeconds": 28800
}

Sends a DM to the manager (resolved by the previous user/get node) and waits up to 8 business hours for a reply. The downstream IfCondition node checks {{ $output.waitPO.replyText }} to route to the "Approved" or "Rejected" path.

Incident Acknowledgement Gate

{
  "resource": "message",
  "operation": "sendAndWait",
  "botToken": "{{ $credentials.slackBotToken }}",
  "channel": "{{ $input.oncallUserId }}",
  "text": ":pager: *P2 Incident* — `{{ $input.serviceName }}` degraded in `{{ $input.region }}`.\nReply *ack* to acknowledge. No reply in 10 minutes escalates to secondary on-call.",
  "timeoutSeconds": 600
}

Pages the primary on-call engineer. If no reply arrives within 600 seconds (10 minutes), the error port fires with status == "timeout", which triggers an escalation to the secondary on-call via a separate message/sendAndWait node.

Block Kit Button Approval

{
  "resource": "message",
  "operation": "sendAndWait",
  "botToken": "{{ $credentials.slackBotToken }}",
  "channel": "{{ $input.reviewerUserId }}",
  "text": "Content review required for article: {{ $input.articleTitle }}",
  "timeoutSeconds": 172800,
  "blocksJson": "[{\"type\":\"section\",\"text\":{\"type\":\"mrkdwn\",\"text\":\"*Content Review Request*\\nArticle: *{{ $input.articleTitle }}*\\nAuthor: {{ $input.authorName }}\\n<{{ $input.previewUrl }}|Preview article>\"}},{\"type\":\"actions\",\"elements\":[{\"type\":\"button\",\"text\":{\"type\":\"plain_text\",\"text\":\"Approve & Publish\"},\"value\":\"approved\",\"style\":\"primary\"},{\"type\":\"button\",\"text\":{\"type\":\"plain_text\",\"text\":\"Request Revisions\"},\"value\":\"revisions\"},{\"type\":\"button\",\"text\":{\"type\":\"plain_text\",\"text\":\"Reject\"},\"value\":\"rejected\",\"style\":\"danger\"}]}]"
}

Presents a structured review card with three buttons. The button value (approved, revisions, or rejected) is captured as replyText in the success port, enabling a three-way branch in the downstream Switch node.