feat: update README with enhanced descriptions and security features; refactor catastrophic guard checks and tool execution handling

src/tool/seqthink.rs

@@ -27,7 +27,8 @@ impl Tool for SeqThink {
         })
     }
 
-    fn run(&self, _ctx: &ToolCtx, _args: &Value) -> Result<String> {
-        Ok(String::new())
+    fn run(&self, _ctx: &ToolCtx, args: &Value) -> Result<String> {
+        let thought = args.get("thought").and_then(|v| v.as_str()).unwrap_or("");
+        Ok(thought.to_string())
     }
 }