feat: update cookbook

Author: patwlan

docs/arc/04-cookbook/weather.md

@@ -29,7 +29,9 @@ agent {
        - Use multiple function calls if more locations are specified.
      """
     }
-    tools = listOf("get_weather")
+    tools {
+        +"get_weather"
+    }
 }
 ```
 
@@ -45,7 +47,8 @@ function(
     name = "get_weather",
     description = "Returns real-time weather information for any location",
     params = types(string("location", "a city to obtain the weather for."))
-) { (location) ->
+) { (arg) ->
+    val location = arg.toString() // Type conversion required, because arg can be any type depending on the params definition.
     val locationSpecified = location != "unknown" && location?.isNotEmpty() == true
     val locationToUse = if (locationSpecified) location else memory("weather_location")
     if (locationToUse == null) {