CLI referenceScripting
bl eval
Evaluate a JavaScript expression (optionally navigate to URL first)
Evaluate a JavaScript expression (optionally navigate to URL first)
Usage
bl eval [url] [expression] [flags]Flags
| Flag | Description |
|---|---|
--stdin | Read expression from stdin |
Global flags
| Flag | Description |
|---|---|
--headless | Hide browser window (visible by default) |
--json | Output as JSON |
-v, --verbose | Enable debug logging |
Examples
bl eval "document.title"
# Evaluates on current page
bl eval https://example.com "document.title"
# Navigates to URL first, then evaluates
echo 'document.title' | bl eval --stdin
# Read expression from stdin (avoids shell quoting issues)