Published: May 20, 2025
We have so many built-in AI API updates to announce at Google I/O 2025. Starting from Chrome 138, the Summarizer API, Language Detector API, and Translator API are available in stable, as is the Prompt API for use in Chrome Extensions.
And we're not done innovating yet!
- The Writer and Rewriter APIs are in origin trials.
- The Prompt API's multimodal capabilities are available to Early Preview Program (EPP) participants.
- The new Proofreader API will soon be available for EPP Participants.
Check out all of the built-in AI API statuses and everything on the web that happened at Google I/O 2025.
Writer and Rewriter APIs in origin trials
| API | Explainer | Web | Extensions | Chrome Status | Intent |
|---|---|---|---|---|---|
| Writer API | GitHub |  Origin trial |
Origin trial |
View | Intent to Experiment |
| Rewriter API | GitHub | Origin trial |
Origin trial |
View | Intent to Experiment |
The Writer API and Rewriter API are now available in origin trials.
For those new to origin trials, these are time-limited programs open to all developers, offering early access to experimental platform features. There may be temporary usage limits, however, developers can integrate these features for live testing and gathering user feedback, with the goal of informing a future launch.
Use cases
With the Writer API, you can help users write new content, based on an initial idea. For example:
- Support users content creation, including reviews, blog posts, or emails.
- Help users write better support requests.
- Draft an introduction for a series of work samples to better capture certain skills.
With the Rewriter API, refine your users' existing text. For example:
- Rewrite a short email so that it sounds more polite and formal.
- Suggest edits to customer reviews to help other customers understand the feedback or remove toxicity.
- Format content to meet the expectations of certain audiences.
Prompt API updated with multimodal capabilities for EPP
The Prompt API with multimodal capabilities is available from Chrome 138 for local experimentation to Early Preview Program (EPP) participants. With this update, the Prompt API supports audio and images in the input, with a return of text output.
Use cases
There are a number of reasons you may consider using multimodal capabilities:
- Allow users to transcribe audio messages sent in a chat application.
- Describe an image uploaded to your website for use in a caption or alt text.
Your feedback helps inform the future of this API and improvements to Gemini Nano. It may even result in dedicated task APIs (such as APIs for audio transcription or image description), ensuring we meet your needs and the needs of your users.
Proofreader API in EPP
| API | Explainer | Web | Extensions | Chrome Status | Intent |
|---|---|---|---|---|---|
| Proofreader API | GitHub |  In EPP |
In EPP |
View | Intent to Prototype |
The Proofreader API will be available from Chrome 139 Canary in for local experimentation Early Preview Program participants. With this API, you can provide interactive proofreading for your users in your web application or extension.
You will be able to decide what API functions you want to use and design how the output appears for your users:
- Correction: Correct user inputs for grammar, spelling, and punctuation.
- Labels: Label each correction by the error type.
- Explanation: Defining what the error is or why the correction was necessary in plain language.
We hope to receive your feedback to update how the Proofreader API works, the quality of the corrections, and general feedback on the API design. The API is subject to change, based on this feedback.
Use cases
There are a number of possible use cases for the Proofreader API, including:
- Correct a document the user is editing in their browser.
- Help your customers send grammatically correct chat messages.
- Edit comments on a blog post or forum.
- Provide corrections in note taking applications.
Demo
Share your feedback
All of these APIs are in active discussion and subject to change. When you start experimenting, we want to hear from you.
- Join the early preview program for an early look at new APIs and access to our mailing list.
- Discover all of the built-in AI APIs, which use Gemini Nano and other expert models in the browser.