notion-mcp-server

append-block-children

Append new blocks as children to a Notion block or page. Supports all block types including paragraphs, headings, lists, code, and images. Use the 'after' parameter to insert at a specific position.

Instructions

Append new blocks as children to a block or page. Supports all block types: paragraph, headings, lists, code, images, etc. Returns the created block IDs. Use the "after" parameter to insert blocks at a specific position.

Tool call template

Replace each placeholder with a value matching the input schema. Only required parameters are included; add optional parameters as needed.

{
  "id": 1,
  "jsonrpc": "2.0",
  "method": "tools/call",
  "params": {
    "arguments": {
      "block_id": "<block_id>",
      "children": "<children>"
    },
    "name": "append-block-children"
  }
}

Input Schema

Name	Required	Description
`block_id`	Yes	Block or page ID
`children`	Yes	Block objects array
`after`	No	Insert after this block ID

Schema Changelog

Changes observed during successful MCP inspections.

First observedv0.14.0May 27, 2026

TDQS

A3.5/5.0

Behavior3/5

Does the description disclose side effects, auth requirements, rate limits, or destructive behavior?

With no annotations, the description fully bears the responsibility. It mentions the tool returns created block IDs, but does not disclose other behavioral aspects like whether the operation is reversible, permission requirements, or rate limits. Adequate but minimal for a mutation tool.

Agents need to know what a tool does to the world before calling it. Descriptions should go beyond structured annotations to explain consequences.

Conciseness5/5

Is the description appropriately sized, front-loaded, and free of redundancy?

The description is concise—two sentences with no wasted words. The purpose is front-loaded, and the tip is relevant and brief.

Shorter descriptions cost fewer tokens and are easier for agents to parse. Every sentence should earn its place.

Completeness4/5

Given the tool's complexity, does the description cover enough for an agent to succeed on first attempt?

Given the tool's simplicity (3 parameters, no output schema, no enums), the description covers the purpose, supported types, output, and a usage tip. It is largely complete but could elaborate on the expected structure of the 'children' array.

Complex tools with many parameters or behaviors need more documentation. Simple tools need less. This dimension scales expectations accordingly.

Parameters4/5

Does the description clarify parameter syntax, constraints, interactions, or defaults beyond what the schema provides?

Schema coverage is 100%, so baseline is 3. The description adds value by explaining that 'children' supports all block types and clarifies the 'after' parameter's purpose, going beyond the schema descriptions.

Input schemas describe structure but not intent. Descriptions should explain non-obvious parameter relationships and valid value ranges.

Purpose4/5

Does the description clearly state what the tool does and how it differs from similar tools?

The description clearly states 'Append new blocks as children to a block or page', specifying the verb and resource. It lists supported block types, adding clarity. However, it does not explicitly differentiate from sibling tools like append-blocks-simple, which limits it to a 4.

Agents choose between tools based on descriptions. A clear purpose with a specific verb and resource helps agents select the right tool.

Usage Guidelines2/5

Does the description explain when to use this tool, when not to, or what alternatives exist?

The description provides a tip on using the 'after' parameter for positioning but lacks any guidance on when to use this tool versus alternatives (e.g., append-blocks-simple, create-page). No explicit when-not or comparative context.

Agents often have multiple tools that could apply. Explicit usage guidance like "use X instead of Y when Z" prevents misuse.