DynamoDB MCP Server

Instructions

Implementation Reference

• src/index.ts:464-483 (handler)

  The handler function that executes the 'put_item' tool. It marshals the provided item and sends a PutItemCommand to the DynamoDB client.

  async function putItem(params: any) {
    try {
      const command = new PutItemCommand({
        TableName: params.tableName,
        Item: marshall(params.item),
      });
      
      await dynamoClient.send(command);
      return {
        success: true,
        message: `Item added successfully to table ${params.tableName}`,
        item: params.item,
      };
    } catch (error) {
      console.error("Error putting item:", error);
      return {
        success: false,
        message: `Failed to put item: ${error}`,
      };
    }

• src/index.ts:165-172 (schema)

  Input schema for the 'put_item' tool, defining required parameters: tableName (string) and item (object).

  inputSchema: {
    type: "object",
    properties: {
      tableName: { type: "string", description: "Name of the table" },
      item: { type: "object", description: "Item to put into the table" },
    },
    required: ["tableName", "item"],
  },

• src/index.ts:162-173 (registration)

  Definition of the PUT_ITEM_TOOL Tool object, which includes the name, description, and input schema for registration.

  const PUT_ITEM_TOOL: Tool = {
    name: "put_item",
    description: "Inserts or replaces an item in a table",
    inputSchema: {
      type: "object",
      properties: {
        tableName: { type: "string", description: "Name of the table" },
        item: { type: "object", description: "Item to put into the table" },
      },
      required: ["tableName", "item"],
    },
  };

• src/index.ts:598-600 (registration)

  Registration of the 'put_item' tool (via PUT_ITEM_TOOL) in the ListToolsRequestHandler, listing it among available tools.

  server.setRequestHandler(ListToolsRequestSchema, async () => ({
    tools: [CREATE_TABLE_TOOL, UPDATE_CAPACITY_TOOL, PUT_ITEM_TOOL, GET_ITEM_TOOL, QUERY_TABLE_TOOL, SCAN_TABLE_TOOL, DESCRIBE_TABLE_TOOL, LIST_TABLES_TOOL, CREATE_GSI_TOOL, UPDATE_GSI_TOOL, CREATE_LSI_TOOL, UPDATE_ITEM_TOOL],
  }));

• src/index.ts:629-631 (registration)

  Dispatch registration in the CallToolRequestHandler switch statement, which calls the putItem handler for the 'put_item' tool.

  case "put_item":
    result = await putItem(args);
    break;