Google Launches Jules API to Automate Developer Workflows

OCT. 3, 2025 — Google has launched the Jules API, a new tool designed to help developers automate, integrate, and innovate across the software development lifecycle. Announced in a blog post by Senior Product Manager Jane Fine, the API aims to simplify complex workflows with its building blocks: Source, Session, and Activity.

How Jules API Works

The API revolves around three core concepts:

• Source: Inputs like GitHub repositories (requires Jules GitHub app).
• Session: A continuous work block akin to a chat session.
• Activity: Individual steps within a session, such as generating plans or sending messages.

Potential Use Cases

Google highlights several innovative applications:

• Bug fixes via Slack: A bot can auto-detect issues, implement fixes, test changes, and create PRs—all while updating users in Slack.
• Backlog automation: Minor bugs or feature requests can be assigned directly to Jules.

Quickstart Guide

Developers can get started in seconds:

1. Obtain an API key from jules.google.com/settings#api.

2. Connect repositories using: curl 'https://jules.googleapis.com/v1alpha/sources'
   -H 'X-Goog-Api-Key: YOUR_API_KEY'

3. Launch a session—for example, to build a boba app: curl 'https://jules.googleapis.com/v1alpha/sessions'
   -X POST
   -H "Content-Type: application/json"
   -H 'X-Goog-Api-Key: YOUR_API_KEY'
   -d '{ "prompt": "Create a boba app!", "sourceContext": { "source": "sources/github/bobalover/boba", "githubRepoContext": { "startingBranch": "main" } }, "title": "Boba App" }'

Future Plans

Google describes this as an early version and encourages developers to share feedback via its Discord channel. Full documentation is available at developers.google.com/jules/api.