Introducing the New v0 API

The v0 API is now available in public beta. Developers can programmatically run v0's app generation agent by sending prompts from their own UIs or pipelines. After generating an app, v0 starts a development server in Vercel Sandbox and provides an embeddable preview URL.

Each chat acts as an isolated workspace for a single app. v0 can read, modify, and execute files within that workspace, and subsequent messages continue from the existing state to further develop the app. A key feature is validating code in the sandbox to detect and fix runtime errors in real time.

The main usage flow is as follows:

• Install the v0 SDK and create a chat with a prompt.
• Use the returned chatId to request subsequent changes to the same app.
• Embed the generated app into your own product via an iframe using a proxy route.
• Deploy to Vercel with a single API call when ready.

Messages contain ordered parts including text, reasoning, file read/write operations, search, bash commands, tool calls, and agent tasks. These can be used to build anything from simple status indicators to lists of changed files and full execution trace views. Usage information is also returned alongside chat and message responses.

Chat creation and message sending support synchronous, asynchronous, and streaming modes. Synchronous mode waits for the completed response, asynchronous mode queues the task and checks for results via webhooks or polling, and streaming mode renders v0's work process in real time.

This enables the construction of white-label app builders, automated app changes based on scripts, CI, and webhooks, and build tools for agents that return executable apps instead of code snippets.