push_flex_message
Send customizable flex messages to LINE users with bubble or carousel layouts for interactive content delivery.
Instructions
Push a highly customizable flex message to a user via LINE. Supports both bubble (single container) and carousel (multiple swipeable bubbles) layouts.
Input Schema
TableJSON Schema
| Name | Required | Description | Default |
|---|---|---|---|
| userId | No | The user ID to receive a message. Defaults to DESTINATION_USER_ID. | U1a2b3c4d5e6f7g8h9i0j1k2l3m4n5o6p |
| message | Yes |
Implementation Reference
- src/tools/pushFlexMessage.ts:38-54 (handler)The core handler function that validates the userId, pushes the flex message to the LINE API client, and returns success or error response.
async ({ userId, message }) => { if (!userId) { return createErrorResponse(NO_USER_ID_ERROR); } try { const response = await this.client.pushMessage({ to: userId, messages: [message as unknown as messagingApi.Message], }); return createSuccessResponse(response); } catch (error) { return createErrorResponse( `Failed to push flex message: ${error.message}`, ); } }, - Zod schema defining the structure of the flex message input, including type, altText, and contents (bubble or carousel).
export const flexMessageSchema = z.object({ type: z.literal("flex").default("flex"), altText: z .string() .describe("Alternative text shown when flex message cannot be displayed."), contents: z .object({ type: z .enum(["bubble", "carousel"]) .describe( "Type of the container. 'bubble' for single container, 'carousel' for multiple swipeable bubbles.", ), }) .passthrough() .describe( "Flexible container structure following LINE Flex Message format. For 'bubble' type, can include header, " + "hero, body, footer, and styles sections. For 'carousel' type, includes an array of bubble containers in " + "the 'contents' property.", ), }); - src/tools/pushFlexMessage.ts:30-55 (registration)Registers the 'push_flex_message' tool with the MCP server, specifying the name, description, input schema (userId and message), and the handler function.
server.tool( "push_flex_message", "Push a highly customizable flex message to a user via LINE. Supports both bubble (single container) and carousel " + "(multiple swipeable bubbles) layouts.", { userId: userIdSchema, message: flexMessageSchema, }, async ({ userId, message }) => { if (!userId) { return createErrorResponse(NO_USER_ID_ERROR); } try { const response = await this.client.pushMessage({ to: userId, messages: [message as unknown as messagingApi.Message], }); return createSuccessResponse(response); } catch (error) { return createErrorResponse( `Failed to push flex message: ${error.message}`, ); } }, ); - src/index.ts:62-62 (registration)Instantiates the PushFlexMessage class with the messaging API client and destination ID, then calls register to add the tool to the MCP server.
new PushFlexMessage(messagingApiClient, destinationId).register(server); - src/tools/pushFlexMessage.ts:23-28 (schema)Zod schema for the userId parameter, with default value from destinationId and description.
const userIdSchema = z .string() .default(this.destinationId) .describe( "The user ID to receive a message. Defaults to DESTINATION_USER_ID.", );