platonai Web Scraping Skill
Description
Extract data from web pages using JavaScript and CSS selectors. This skill uses real browser automation to navigate to pages and extract content using JavaScript execution. It can extract webpage titles using document.title and body text using document.body.textContent, providing actual content from live web pages.
Dependencies
None
Parameters
| Parameter | Type | Required | Default | Description |
|---|---|---|---|---|
| url | String | Yes | - | The URL of the web page to scrape |
| selector | String | Yes | - | CSS selector to target specific elements |
| attributes | List | No | ["text"] | List of attributes to extract (e.g., "text", "href", "src") |
Return Value
Returns a SkillResult with the following data structure:
{
"url": "string",
"selector": "string",
"attributes": ["string"],
"data": "extracted content"
}
Usage Examples
Basic Text Extraction
val result = registry.execute(
skillId = "web-scraping",
context = context,
params = mapOf(
"url" to "https://example.com",
"selector" to ".content"
)
)
Extract Multiple Attributes
val result = registry.execute(
skillId = "web-scraping",
context = context,
params = mapOf(
"url" to "https://example.com/products",
"selector" to "a.product-link",
"attributes" to listOf("text", "href")
)
)
Tool Call Specification
ToolSpec(
domain = "skill.debug.scraping",
method = "extract",
arguments = [
"url: String",
"selector: String",
"attributes: List<String> = listOf('text')"
],
returnType = "Map<String, Any>",
description = "Extract data from a web page using CSS selectors"
)
Error Handling
The skill returns a failure result in the following cases:
- Missing required parameter
url - Missing required parameter
selector - Invalid URL format (must start with http:// or https://)
Lifecycle Hooks
onLoad
Initializes resources and loads configurations when the skill is registered.
onBeforeExecute
Validates URL format before execution. Returns false if URL doesn't start with http:// or https://.
onAfterExecute
Records the timestamp of successful scraping operations in shared resources.
validate
Validates skill configuration and environment. Always returns true for this skill.
Implementation Notes
- Headless mode is the default for AI agents: Always open browsers in headless mode unless the user explicitly requests a visible browser window (e.g., "show me the browser", "open visibly", "headed"). Headless mode is faster, uses fewer resources, and avoids unnecessary GUI windows.
- Uses JavaScript execution via WebDriver.evaluate() to extract real webpage content
- Extracts document title using
document.title - Extracts page text using
document.body.textContent - Falls back to PulsarSession-based extraction if WebDriver is not directly available
- Returns simulated data only if neither WebDriver nor PulsarSession is available in the skill context
- Supports both synchronous and asynchronous execution patterns
- Thread-safe and can be used in concurrent environments
- Text content is limited to 5000 characters to avoid overwhelming responses