[Home](./index.md) > [puppeteer](./puppeteer.md) > [Protocol](./puppeteer.protocol.md) > [Runtime](./puppeteer.protocol.runtime.md) > [ExecutionContextDescription](./puppeteer.protocol.runtime.executioncontextdescription.md) > [id](./puppeteer.protocol.runtime.executioncontextdescription.id.md) ## Protocol.Runtime.ExecutionContextDescription.id property Unique id of the execution context. It can be used to specify in which execution context script evaluation should be performed. Signature: ```typescript id: ExecutionContextId; ```