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web api static method

Summarizer: availability() static method

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Limited availabilitySecure context

The availability() static method of the Summarizer interface returns an enumerated value that indicates whether the browser AI model supports (or will support) a given Summarizer configuration.

Syntax

Summarizer.availability()
Summarizer.availability(options)

Parameters

  • options Optional
    • : An options object specifying a possible configuration for a Summarizer. Possible values include:
      • expectedInputLanguages
        • : An array of strings equal to BCP 47 language tags specifying the expected languages of the input text. Defaults to ["en"].
      • expectedContextLanguages
        • : An array of strings equal to BCP 47 language tags specifying the expected languages of any provided context strings (either the sharedContext passed to the Summarizer, or a context specified during a summarize() or summarizeStreaming() call). Defaults to ["en"].
      • format
        • : An enumerated value specifying the text format you want summaries returned in. Defaults to markdown.
      • length
        • : An enumerated value specifying the relative length for the generated summaries. Defaults to short.
      • outputLanguage
        • : A string equal to a BCP 47 language tag specifying the expected language of summaries generated by the Summarizer. Defaults to en.
      • type
        • : An enumerated value specifying the type of summary you want this Summarizer to generate. Defaults to key-points.

Return value

A Promise that fulfills with an enumerated value indicating whether support is available (or will be available) for a given Summarizer configuration, or null if support could not be determined.

Possible values include:

  • available
    • : The browser supports the given configuration and can be used immediately.
  • downloadable
    • : The browser supports the given configuration, but it first needs to download an AI model, or some fine-tuning data for the model.
  • downloading
    • : The browser supports the given configuration, but it needs to finish an ongoing download before it can proceed.
  • unavailable

Exceptions

  • NotSupportedError DOMException
    • : Thrown if the provided context is not in language the Summarizer supports.
  • UnknownError DOMException
    • : Thrown if the measureInputUsage() call failed for any other reason, or a reason the user agent did not wish to disclose.

Examples

Basic availability() usage

async function getSummarizer() {
  const options = {
    sharedContext: "This is a scientific article",
    type: "key-points",
    format: "markdown",
    length: "medium",
  };

  const availability = await Summarizer.availability(options);
  if (availability === "unavailable") {
    // The Summarizer API isn't usable
    return undefined;
  } else if (availability === "available") {
    // The Summarizer API can be used immediately
    return Summarizer.create(options);
  }
  // The Summarizer API can be used after the model is downloaded
  const summarizer = await Summarizer.create(options);
  summarizer.addEventListener("downloadprogress", (e) => {
    console.log(`Downloaded ${e.loaded * 100}%`);
  });
  return summarizer;
}

Detecting language support

async function langSupport(lang) {
  const availability = await Summarizer.availability({
    expectedInputLanguages: [lang],
  });
  return availability;
}

langSupport("en-US");
langSupport("fr");
langSupport("zh-CN");

Specifications

SpecificationsStandards references are available on the canonical MDN page.

Browser compatibility

Browser compatibilityCompatibility data is available on the canonical MDN page.

See also