[Home](./index.md) > [puppeteer](./puppeteer.md) > [Coverage](./puppeteer.coverage.md) > [startJSCoverage](./puppeteer.coverage.startjscoverage.md) ## Coverage.startJSCoverage() method Signature: ```typescript startJSCoverage(options?: JSCoverageOptions): Promise; ``` ## Parameters | Parameter | Type | Description | | --- | --- | --- | | options | [JSCoverageOptions](./puppeteer.jscoverageoptions.md) | defaults to { resetOnNavigation : true, reportAnonymousScripts : false } | Returns: Promise<void> Promise that resolves when coverage is started. ## Remarks Anonymous scripts are ones that don't have an associated url. These are scripts that are dynamically created on the page using `eval` or `new Function`. If `reportAnonymousScripts` is set to `true`, anonymous scripts will have `__puppeteer_evaluation_script__` as their URL.