use std::path::PathBuf;
use async_trait::async_trait;
use serde_json::{json, Value};
use agent_base::{AgentError, AgentResult, Tool, ToolContext, ToolControlFlow, ToolOutput};
pub struct FileExistsTool {
pub workspace: PathBuf,
}
#[async_trait]
impl Tool for FileExistsTool {
fn name(&self) -> &'static str {
"file_exists"
}
fn definition(&self) -> Value {
json!({
"type": "function",
"function": {
"name": "file_exists",
"description": "Check if a file exists",
"parameters": {
"type": "object",
"properties": {
"path": {
"type": "string",
"description": "Path to the file or directory to check"
}
},
"required": ["path"]
}
}
})
}
async fn call(&self, args: &Value, _ctx: &ToolContext) -> AgentResult<ToolOutput> {
let path = args["path"]
.as_str()
.ok_or_else(|| AgentError::internal("missing 'path' argument"))?;
let full_path = self.workspace.join(path);
let metadata = tokio::fs::metadata(&full_path).await;
let exists = metadata.is_ok();
let is_file = metadata
.as_ref()
.is_ok_and(|m| m.is_file());
let is_dir = metadata
.as_ref()
.is_ok_and(|m| m.is_dir());
Ok(ToolOutput {
summary: if exists {
format!("{} exists", path)
} else {
format!("{} does not exist", path)
},
raw: Some(json!({"path": path, "exists": exists, "is_file": is_file, "is_dir": is_dir})),
control_flow: ToolControlFlow::Break,
truncation: None,
})
}
}