block/appendChildren

When to Use

• Deployment log entries: Append a paragraph block to an incident or deployment page each time a CI/CD pipeline step completes, building a running log of deployment events on the page.
• Weekly metrics append: Each week, append a new section with the latest metrics to a running report page rather than creating a new page per week.
• Action items after meeting summarization: After a FlowAiAgent node extracts action items from meeting notes, append them as to-do blocks back to the meeting notes page.
• Bug tracking annotation: When a bug report is triaged, append a structured summary block to the bug page with severity assessment and assigned team.
• Test results recording: After a test suite runs, append a code block or table block containing test output to a QA tracking page.

Configuration

Authentication

Operation Fields

Sample Configuration

{
  "resource": "block",
  "operation": "appendChildren",
  "AuthenticationMethod": "ApiToken",
  "ApiToken": "{{ $credentials.notionApiToken }}",
  "BlockId": "{{ $json.pageId }}",
  "Blocks": [
    {
      "object": "block",
      "type": "heading_2",
      "heading_2": {
        "rich_text": [{ "type": "text", "text": { "content": "Deployment — {{ $now | date: 'YYYY-MM-DD HH:mm' }} UTC" } }]
      }
    },
    {
      "object": "block",
      "type": "paragraph",
      "paragraph": {
        "rich_text": [{ "type": "text", "text": { "content": "Environment: {{ $json.environment }}\nBuild: {{ $json.buildId }}\nStatus: {{ $json.status }}" } }]
      }
    },
    {
      "object": "block",
      "type": "divider",
      "divider": {}
    }
  ]
}

Block Type Reference

Validation Errors

Output

Success Port

Error Port

On failure the error port receives errorCode, message, and httpStatus. A malformed block at any position causes the entire call to fail — none of the blocks in the array are appended on error.

Sample Output

{
  "results": [
    {
      "id": "a3b4c5d6-e7f8-9012-abcd-234567890123",
      "type": "heading_2",
      "created_time": "2024-06-11T14:32:00.000Z",
      "heading_2": {
        "rich_text": [{ "plain_text": "Deployment — 2024-06-11 14:32 UTC" }]
      }
    },
    {
      "id": "b4c5d6e7-f8a9-0123-bcde-345678901234",
      "type": "paragraph",
      "created_time": "2024-06-11T14:32:00.000Z",
      "paragraph": {
        "rich_text": [{ "plain_text": "Environment: production\nBuild: build-4821\nStatus: Success" }]
      }
    }
  ]
}

Expression Reference

Node Policies & GuardRails

Workflow Examples

Example 1 — Running Deployment Log

Each time a deployment pipeline fires, append a timestamped entry to a central deployment log page.

// Step 1: WebhookTrigger (CI/CD pipeline complete)
// Step 2: block/appendChildren
{
  "BlockId": "{{ $vars.deploymentLogPageId }}",
  "Blocks": [
    {
      "object": "block", "type": "heading_3",
      "heading_3": { "rich_text": [{ "text": { "content": "{{ $now | date: 'YYYY-MM-DD HH:mm' }} — {{ $json.service }}" } }] }
    },
    {
      "object": "block", "type": "bulleted_list_item",
      "bulleted_list_item": { "rich_text": [{ "text": { "content": "Status: {{ $json.status }}" } }] }
    },
    {
      "object": "block", "type": "bulleted_list_item",
      "bulleted_list_item": { "rich_text": [{ "text": { "content": "Build: {{ $json.buildId }}" } }] }
    },
    { "object": "block", "type": "divider", "divider": {} }
  ]
}

Example 2 — Append AI Summary to Meeting Notes

After summarizing a meeting page with FlowAiAgent, append the summary and action items back to the original page.

// Step 1: block/getChildren (read existing meeting notes)
// Step 2: FlowAiAgent (summarize + extract action items)
// Step 3: Function node — build block array from AI output
const blocks = [
  { object: "block", type: "divider", divider: {} },
  { object: "block", type: "heading_2", heading_2: { rich_text: [{ text: { content: "AI Summary" } }] } },
  { object: "block", type: "paragraph", paragraph: { rich_text: [{ text: { content: $json.summary } }] } },
  { object: "block", type: "heading_3", heading_3: { rich_text: [{ text: { content: "Action Items" } }] } },
  ...$json.actionItems.map(item => ({
    object: "block", type: "to_do",
    to_do: { rich_text: [{ text: { content: item } }], checked: false }
  }))
];
return { blocks };
// Step 4: block/appendChildren with generated blocks

Example 3 — Batch Large Content Append

Append more than 100 blocks by splitting into batches.

// Step 1: Build allBlocks array (200 items)
// Step 2: Split into batches of 100
const batches = [];
for (let i = 0; i < allBlocks.length; i += 100) {
  batches.push(allBlocks.slice(i, i + 100));
}
// Step 3: Loop over batches
// Step 4 per batch: block/appendChildren with batch items