Improve docs on error reporting

docs/6/digging-deeper/error-handling.md

@@ -14,6 +14,18 @@ be implemented by Exceptions to control how they are rendered to the client.
 
 Head over their [Error Handling docs](https://webonyx.github.io/graphql-php/error-handling) to learn more.
 
+## Error Reporting
+
+Lighthouse will catch exceptions thrown during the execution of a query and return them as part of the response.
+
+The error handler `Nuwave\Lighthouse\Execution\ReportingErrorHandler` is included in the default configuration
+and reports non-client-safe errors through the default Laravel exception handler.
+
+Client-safe errors are assumed to be something that:
+- a client can understand and handle
+- were caused by client misuse, e.g. wrong syntax, authentication, validation
+Thus, they are typically not actionable for server developers.
+
 ## Additional Error Information
 
 The interface [`GraphQL\Error\ProvidesExtensions`](https://github.com/webonyx/graphql-php/blob/master/src/Error/ProvidesExtensions.php)
@@ -116,8 +128,7 @@ Add them to your `lighthouse.php` config file, for example:
 ```php
 'error_handlers' => [
     \App\GraphQL\CountErrorHandler::class,
-    \Nuwave\Lighthouse\Execution\ValidationErrorHandler::class,
-    \Nuwave\Lighthouse\Execution\ReportingErrorHandler::class,
+    ...
 ],
 ```
 

docs/master/digging-deeper/error-handling.md

@@ -14,6 +14,18 @@ be implemented by Exceptions to control how they are rendered to the client.
 
 Head over their [Error Handling docs](https://webonyx.github.io/graphql-php/error-handling) to learn more.
 
+## Error Reporting
+
+Lighthouse will catch exceptions thrown during the execution of a query and return them as part of the response.
+
+The error handler `Nuwave\Lighthouse\Execution\ReportingErrorHandler` is included in the default configuration
+and reports non-client-safe errors through the default Laravel exception handler.
+
+Client-safe errors are assumed to be something that:
+- a client can understand and handle
+- were caused by client misuse, e.g. wrong syntax, authentication, validation
+Thus, they are typically not actionable for server developers.
+
 ## Additional Error Information
 
 The interface [`GraphQL\Error\ProvidesExtensions`](https://github.com/webonyx/graphql-php/blob/master/src/Error/ProvidesExtensions.php)
@@ -116,8 +128,7 @@ Add them to your `lighthouse.php` config file, for example:
 ```php
 'error_handlers' => [
     \App\GraphQL\CountErrorHandler::class,
-    \Nuwave\Lighthouse\Execution\ValidationErrorHandler::class,
-    \Nuwave\Lighthouse\Execution\ReportingErrorHandler::class,
+    ...
 ],
 ```