Content helpers

A tool result carries an array of MCP content blocks. These helpers build a correct block, so you do not write the shape by hand.

import { text, image, resourceLink } from "ng-mcp-ui/server";

return {
  content: [text("Here is the chart."), image(png, "image/png")],
  structuredContent: { total: 42 },
};

The helpers

Helper	Signature
text	(value: string, annotations?) => TextContent
image	(data: string | Uint8Array, mimeType: string, annotations?) => ImageContent
audio	(data: string | Uint8Array, mimeType: string, annotations?) => AudioContent
resourceLink	(link: { uri, name, title?, description?, mimeType?, size? }, annotations?) => ResourceLink
embeddedResource	(resource: { uri, mimeType?, text } | { uri, mimeType?, blob }, annotations?) => EmbeddedResource

image and audio accept a base64 string or a Uint8Array. The helper encodes a Uint8Array for you.

embeddedResource accepts a text resource or a binary resource. Give text for one, and a base64 blob for the other.

Annotations

Each helper takes an optional annotations object.

Field	Type	Purpose
audience	("user" | "assistant")[]	Who the block is for.
priority	number	How important the block is.
lastModified	string	An ISO timestamp.

text("Internal note.", { audience: ["assistant"], priority: 0.2 });

Use audience: ["assistant"] for content that helps the model but that the user does not need to read.

normalizeContent

normalizeContent(content: HandlerContent | undefined): ContentBlock[]

The server calls this function on the content field of each handler result. It accepts a loose value and gives back a correct array of blocks.

You return	You get
A string	One text block
One block	An array with that block
An array of blocks	The same array, unchanged
undefined	An empty array

Therefore the short form is correct:

return { content: "Created the poll." };

Call normalizeContent yourself only when you build a result outside a tool handler.

Related

• registerTool
• FileRef