browser_evaluate
Run JavaScript in the browser page and return the result as text.
Parameters
| Parameter | Type | Required | Description |
|---|---|---|---|
sessionId | string | Yes | Session ID from browser_navigate |
script | string | Yes | JavaScript expression to evaluate |
caption | string | No | Short reason for the evaluation, echoed in the MCP/CLI evidence text |
Examples
Run document.title to get the page titleRun document.querySelectorAll('a').length to count all linksRun JSON.stringify(performance.timing) to get performance timing dataNotes
- Executes in the browser context with full DOM access
- Returns the current URL, session ID, truncated script, and result so chat/CLI transcripts show what was inspected
- Useful for extracting data, checking state, or triggering actions not covered by other tools
- Has access to
window,document,localStorage, etc.