[Home](./index.md) > [puppeteer](./puppeteer.md) > [Protocol](./puppeteer.protocol.md) > [Tracing](./puppeteer.protocol.tracing.md) > [StreamFormat](./puppeteer.protocol.tracing.streamformat.md) ## Protocol.Tracing.StreamFormat type Data format of a trace. Can be either the legacy JSON format or the protocol buffer format. Note that the JSON format will be deprecated soon. Signature: ```typescript export type StreamFormat = ('json' | 'proto'); ```