notion_retrieve_block_children
Retrieve child content from a Notion block to access nested information, supporting pagination and multiple output formats.
Instructions
Retrieve the children of a block
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| block_id | Yes | The ID of the block.It should be a 32-character string (excluding hyphens) formatted as 8-4-4-4-12 with hyphens (-). | |
| start_cursor | No | Pagination cursor for next page of results | |
| page_size | No | Number of results per page (max 100) | |
| format | No | Specify the response format. 'json' returns the original data structure, 'markdown' returns a more readable format. Use 'markdown' when the user only needs to read the page and isn't planning to write or modify it. Use 'json' when the user needs to read the page with the intention of writing to or modifying it. | markdown |
Implementation Reference
- src/client/index.ts:60-78 (handler)Core implementation of the tool: NotionClientWrapper.retrieveBlockChildren method that makes the GET request to Notion API /blocks/{block_id}/children with optional pagination.async retrieveBlockChildren( block_id: string, start_cursor?: string, page_size?: number ): Promise<ListResponse> { const params = new URLSearchParams(); if (start_cursor) params.append("start_cursor", start_cursor); if (page_size) params.append("page_size", page_size.toString()); const response = await fetch( `${this.baseUrl}/blocks/${block_id}/children?${params}`, { method: "GET", headers: this.headers, } ); return response.json(); }
- src/server/index.ts:76-87 (handler)MCP server dispatch handler for the tool call, validates args and delegates to NotionClientWrapper.case "notion_retrieve_block_children": { const args = request.params .arguments as unknown as args.RetrieveBlockChildrenArgs; if (!args.block_id) { throw new Error("Missing required argument: block_id"); } response = await notionClient.retrieveBlockChildren( args.block_id, args.start_cursor, args.page_size ); break;
- src/types/schemas.ts:59-81 (schema)Tool schema definition: name, description, and inputSchema for validation.export const retrieveBlockChildrenTool: Tool = { name: "notion_retrieve_block_children", description: "Retrieve the children of a block", inputSchema: { type: "object", properties: { block_id: { type: "string", description: "The ID of the block." + commonIdDescription, }, start_cursor: { type: "string", description: "Pagination cursor for next page of results", }, page_size: { type: "number", description: "Number of results per page (max 100)", }, format: formatParameter, }, required: ["block_id"], }, };
- src/types/args.ts:20-25 (schema)TypeScript interface for tool arguments used in server handler.export interface RetrieveBlockChildrenArgs { block_id: string; start_cursor?: string; page_size?: number; format?: "json" | "markdown"; }
- src/server/index.ts:304-325 (registration)Tool is registered by including retrieveBlockChildrenTool in the list of available tools served in ListToolsRequest response.schemas.appendBlockChildrenTool, schemas.retrieveBlockTool, schemas.retrieveBlockChildrenTool, schemas.deleteBlockTool, schemas.updateBlockTool, schemas.retrievePageTool, schemas.updatePagePropertiesTool, schemas.listAllUsersTool, schemas.retrieveUserTool, schemas.retrieveBotUserTool, schemas.createDatabaseTool, schemas.queryDatabaseTool, schemas.retrieveDatabaseTool, schemas.updateDatabaseTool, schemas.createDatabaseItemTool, schemas.createCommentTool, schemas.retrieveCommentsTool, schemas.searchTool, ]; return { tools: filterTools(allTools, enabledToolsSet), };