Notion MCP Server

Instructions

Implementation Reference

• server.js:538-563 (handler)

  Handler logic for the 'append-block-children' tool. Destructures arguments, cleans block_id and after, constructs params, calls notion.blocks.children.append, and returns the JSON response.

  else if (name === "append-block-children") {
    let { block_id, children, after } = args;
    
    // Remove dashes if present in block_id
    block_id = block_id.replace(/-/g, "");
  
    const params = {
      block_id,
      children,
    };
  
    if (after) {
      params.after = after.replace(/-/g, ""); // Ensure after ID is properly formatted
    }
  
    const response = await notion.blocks.children.append(params);
  
    return {
      content: [
        {
          type: "text",
          text: JSON.stringify(response, null, 2),
        },
      ],
    };
  }

• server.js:218-239 (registration)

  Tool registration in the tools/list response, including name, description, and input schema for 'append-block-children'.

  {
    name: "append-block-children",
    description: "Append blocks to a parent block",
    inputSchema: {
      type: "object",
      properties: {
        block_id: {
          type: "string",
          description: "ID of the parent block (page or block)"
        },
        children: {
          type: "array",
          description: "List of block objects to append"
        },
        after: {
          type: "string",
          description: "Optional ID of an existing block to append after"
        }
      },
      required: ["block_id", "children"]
    }
  },