use crate::error::{BrowserError, Result};
use crate::tools::{Tool, ToolContext, ToolResult};
use schemars::JsonSchema;
use serde::{Deserialize, Serialize};
use serde_json::Value;
#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
pub struct EvaluateParams {
pub code: String,
#[serde(default)]
pub await_promise: bool,
#[serde(default)]
pub confirm_unsafe: bool,
}
#[derive(Default)]
pub struct EvaluateTool;
#[derive(Debug, Clone, Serialize, Deserialize, JsonSchema)]
pub struct EvaluateOutput {
pub result: Value,
}
impl Tool for EvaluateTool {
type Params = EvaluateParams;
type Output = EvaluateOutput;
fn name(&self) -> &str {
"evaluate"
}
fn description(&self) -> &str {
"Run arbitrary JavaScript when inspect_node is insufficient. Requires confirm_unsafe=true."
}
fn execute_typed(
&self,
params: EvaluateParams,
context: &mut ToolContext,
) -> Result<ToolResult> {
if !params.confirm_unsafe {
return Err(BrowserError::InvalidArgument(
"evaluate requires confirm_unsafe=true".to_string(),
));
}
context.record_browser_evaluation();
let result = context
.session
.evaluate(¶ms.code, params.await_promise)?;
let result_value = result.value.unwrap_or(Value::Null);
Ok(context.finish(ToolResult::success_with(EvaluateOutput {
result: result_value,
})))
}
}
#[cfg(test)]
mod tests {
use super::*;
use crate::browser::BrowserSession;
use crate::browser::backend::FakeSessionBackend;
use crate::tools::{OPERATION_METRICS_METADATA_KEY, Tool, ToolContext};
#[test]
fn test_evaluate_tool_records_browser_evaluation_metrics() {
let session = BrowserSession::with_test_backend(FakeSessionBackend::new());
let tool = EvaluateTool;
let mut context = ToolContext::new(&session);
let result = tool
.execute_typed(
EvaluateParams {
code: "document.readyState".to_string(),
await_promise: false,
confirm_unsafe: true,
},
&mut context,
)
.expect("evaluate should succeed");
assert!(result.success);
let metrics = result.metadata[OPERATION_METRICS_METADATA_KEY]
.as_object()
.expect("metrics metadata should be present");
assert_eq!(metrics["browser_evaluations"].as_u64(), Some(1));
}
}