Assets

Building and validating inklet assets — text, links, images, and files, with accepted content types and size limits.

An asset is one piece of raw input. inklet.assets.* builds them and validates them in your process, so a malformed push fails before it costs a round trip.

inklet.assets.text("Milk, eggs, coffee");
inklet.assets.link("https://example.com/report");
inklet.assets.image({ data, filename: "chart.png", contentType: "image/png" });
inklet.assets.file({ data, filename: "menu.pdf", contentType: "application/pdf" });

Limits

Limit	Value
Bytes per binary asset	10 MiB (`MAX_ASSET_SIZE_BYTES`)
Assets per Content	50 (`MAX_ASSETS_PER_CONTENT`)
Minimum	At least one asset, and binaries cannot be empty

`text()`

text(text: string): TextAsset

Must contain at least one non-whitespace character. Empty or whitespace-only text throws ConfigurationError.

`link()`

link(url: string): LinkAsset

Must be an absolute HTTP or HTTPS URL with no embedded credentials. The URL is normalized (trimmed and re-serialized) before being stored on the asset.

inklet fetches and summarises the link during the fetching_links stage — a link is a source, not just a citation.

`image()`

image(input: { data: BinaryAssetData; filename: string; contentType: AllowedImageContentType }): ImageAsset

Accepted `contentType`	Notes
`image/png`	Lossless; the safest default for charts and text
`image/jpeg`	Photographs
`image/gif`	First frame is used
`image/webp`	Both lossy and lossless
`image/svg+xml`	Rasterised server-side

Hardcode Push is narrower — it accepts only PNG and JPEG, since it renders your image directly to the panel.

`file()`

file(input: { data: BinaryAssetData; filename: string; contentType: AllowedFileContentType }): FileAsset

Accepted `contentType`	Notes
`application/pdf`	Multi-page documents
`text/plain`	Plain text files
`text/markdown`	Structure is understood, not shown as source
`application/json`	Summarised as data, not printed raw

Binary data

type BinaryAssetData = Blob | ArrayBuffer | ArrayBufferView;

So all of these work:

import { readFile } from "node:fs/promises";

// Buffer (a Uint8Array, so an ArrayBufferView)
inklet.assets.image({
  data: await readFile("chart.png"),
  filename: "chart.png",
  contentType: "image/png",
});

// Blob
inklet.assets.file({
  data: new Blob([json], { type: "application/json" }),
  filename: "data.json",
  contentType: "application/json",
});

// ArrayBuffer
inklet.assets.image({
  data: await (await fetch(url)).arrayBuffer(),
  filename: "remote.png",
  contentType: "image/png",
});

If you pass a Blob that already has a type, it must match the declared contentType. A mismatch throws — this catches a JPEG mislabelled as a PNG before the render worker has to deal with it.

Types

Prop

Type

Prop

Type

Prop

Type

Prop

Type

InkletAsset is the exported union of these four shapes.

The content-type unions are exported, so you can narrow against them:

import {
  ALLOWED_IMAGE_CONTENT_TYPES,
  ALLOWED_FILE_CONTENT_TYPES,
  type AllowedImageContentType,
} from "@inklethq/sdk";

function isSupportedImage(type: string): type is AllowedImageContentType {
  return (ALLOWED_IMAGE_CONTENT_TYPES as readonly string[]).includes(type);
}

Validation errors

Every failure below is a ConfigurationError thrown locally, before a request:

Empty or whitespace-only text
A link that is not absolute HTTP(S), or carries credentials
A missing or blank filename
A contentType outside the allowed list for that asset kind
A Blob whose own type contradicts the declared contentType
Zero bytes, or more than 10 MiB
Data that is not a Blob, ArrayBuffer, or ArrayBufferView

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