diff --git a/src/error.rs b/src/error.rs
index e42dacf7..3792b196 100644
--- a/src/error.rs
+++ b/src/error.rs
@@ -1,5 +1,6 @@
 use crate::{Pos, QueryPathNode, Value};
-use std::fmt::{Debug, Display};
+use std::fmt::{Debug, Display, Formatter, Result as FmtResult};
+use std::ops::Deref;
 use thiserror::Error;
 
 /// An error in the format of an input value.
@@ -382,6 +383,27 @@ pub struct RuleError {
     pub message: String,
 }
 
+impl Display for RuleError {
+    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
+        for (idx, loc) in self.locations.iter().enumerate() {
+            if idx == 0 {
+                write!(f, "[")?;
+            } else {
+                write!(f, ", ")?;
+            }
+
+            write!(f, "{}:{}", loc.line, loc.column)?;
+
+            if idx == self.locations.len() - 1 {
+                write!(f, "] ")?;
+            }
+        }
+
+        write!(f, "{}", self.message)?;
+        Ok(())
+    }
+}
+
 /// An error serving a GraphQL query.
 #[derive(Debug, Error, PartialEq)]
 pub enum Error {
@@ -403,9 +425,45 @@ pub enum Error {
     },
 
     /// The query statement verification failed.
-    #[error("Rule error")]
+    #[error("Rule error:\n{errors}")]
     Rule {
         /// List of errors.
-        errors: Vec<RuleError>,
+        errors: RuleErrors,
     },
 }
+
+/// A collection of RuleError.
+#[derive(Debug, PartialEq)]
+pub struct RuleErrors(Vec<RuleError>);
+
+impl From<Vec<RuleError>> for RuleErrors {
+    fn from(errors: Vec<RuleError>) -> Self {
+        Self(errors)
+    }
+}
+
+impl Deref for RuleErrors {
+    type Target = Vec<RuleError>;
+
+    fn deref(&self) -> &Self::Target {
+        &self.0
+    }
+}
+
+impl IntoIterator for RuleErrors {
+    type Item = RuleError;
+    type IntoIter = std::vec::IntoIter<RuleError>;
+
+    fn into_iter(self) -> Self::IntoIter {
+        self.0.into_iter()
+    }
+}
+
+impl Display for RuleErrors {
+    fn fmt(&self, f: &mut Formatter<'_>) -> FmtResult {
+        for err in &self.0 {
+            writeln!(f, "  {}", err)?;
+        }
+        Ok(())
+    }
+}
diff --git a/src/extensions/logger.rs b/src/extensions/logger.rs
index 2e078611..4aad23bb 100644
--- a/src/extensions/logger.rs
+++ b/src/extensions/logger.rs
@@ -94,7 +94,7 @@ impl Extension for Logger {
                 }
             }
             Error::Rule { errors } => {
-                for error in errors {
+                for error in errors.iter() {
                     let locations = error
                         .locations
                         .iter()
diff --git a/src/extensions/tracing.rs b/src/extensions/tracing.rs
index f6d9a25b..56ea2f82 100644
--- a/src/extensions/tracing.rs
+++ b/src/extensions/tracing.rs
@@ -46,69 +46,69 @@ impl Extension for Tracing {
     fn parse_end(&mut self, _document: &ExecutableDocument) {
         self.parse
             .take()
-            .unwrap()
-            .with_subscriber(|(id, d)| d.exit(id));
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
     }
 
     fn validation_start(&mut self) {
-        let parent = self.root.as_ref().unwrap();
-        let validation_span = span!(
-            target: "async_graphql::graphql",
-            parent: parent,
-            Level::INFO,
-            "validation"
-        );
-        validation_span.with_subscriber(|(id, d)| d.enter(id));
-        self.validation.replace(validation_span);
+        if let Some(parent) = &self.root {
+            let validation_span = span!(
+                target: "async_graphql::graphql",
+                parent: parent,
+                Level::INFO,
+                "validation"
+            );
+            validation_span.with_subscriber(|(id, d)| d.enter(id));
+            self.validation.replace(validation_span);
+        }
     }
 
     fn validation_end(&mut self) {
         self.validation
             .take()
-            .unwrap()
-            .with_subscriber(|(id, d)| d.exit(id));
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
     }
 
     fn execution_start(&mut self) {
-        let parent = self.root.as_ref().unwrap();
-        let execute_span = span!(
-            target: "async_graphql::graphql",
-            parent: parent,
-            Level::INFO,
-            "execute"
-        );
-        execute_span.with_subscriber(|(id, d)| d.enter(id));
-        self.execute.replace(execute_span);
+        if let Some(parent) = &self.root {
+            let execute_span = span!(
+                target: "async_graphql::graphql",
+                parent: parent,
+                Level::INFO,
+                "execute"
+            );
+            execute_span.with_subscriber(|(id, d)| d.enter(id));
+            self.execute.replace(execute_span);
+        }
     }
 
     fn execution_end(&mut self) {
         self.execute
             .take()
-            .unwrap()
-            .with_subscriber(|(id, d)| d.exit(id));
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
 
         self.root
             .take()
-            .unwrap()
-            .with_subscriber(|(id, d)| d.exit(id));
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
     }
 
     fn resolve_start(&mut self, info: &ResolveInfo<'_>) {
         let parent_span = match info.resolve_id.parent {
-            Some(parent_id) if parent_id > 0 => self.fields.get(&parent_id).unwrap(),
-            _ => self.execute.as_ref().unwrap(),
+            Some(parent_id) if parent_id > 0 => self.fields.get(&parent_id),
+            _ => self.execute.as_ref(),
         };
 
-        let span = span!(
-            target: "async_graphql::graphql",
-            parent: parent_span,
-            Level::INFO,
-            "field",
-            id = %info.resolve_id.current,
-            path = %info.path_node
-        );
-        span.with_subscriber(|(id, d)| d.enter(id));
-        self.fields.insert(info.resolve_id.current, span);
+        if let Some(parent_span) = parent_span {
+            let span = span!(
+                target: "async_graphql::graphql",
+                parent: parent_span,
+                Level::INFO,
+                "field",
+                id = %info.resolve_id.current,
+                path = %info.path_node
+            );
+            span.with_subscriber(|(id, d)| d.enter(id));
+            self.fields.insert(info.resolve_id.current, span);
+        }
     }
 
     fn resolve_end(&mut self, info: &ResolveInfo<'_>) {
@@ -118,6 +118,24 @@ impl Extension for Tracing {
     }
 
     fn error(&mut self, err: &Error) {
-        tracing::error!(target: "async_graphql::graphql", error = %err);
+        tracing::error!(target: "async_graphql::graphql", error = %err.to_string());
+
+        for span in self.fields.values() {
+            span.with_subscriber(|(id, d)| d.exit(id));
+        }
+        self.fields.clear();
+
+        self.execute
+            .take()
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
+        self.validation
+            .take()
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
+        self.parse
+            .take()
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
+        self.root
+            .take()
+            .and_then(|span| span.with_subscriber(|(id, d)| d.exit(id)));
     }
 }
diff --git a/src/serialize_resp.rs b/src/serialize_resp.rs
index 9a568d9f..a9c267ff 100644
--- a/src/serialize_resp.rs
+++ b/src/serialize_resp.rs
@@ -72,7 +72,7 @@ impl Serialize for Error {
             }
             Error::Rule { errors } => {
                 let mut seq = serializer.serialize_seq(Some(errors.len()))?;
-                for error in errors {
+                for error in errors.iter() {
                     seq.serialize_element(&serde_json::json!({
                         "message": error.message,
                         "locations": error.locations.iter().map(|pos| serde_json::json!({"line": pos.line, "column": pos.column})).collect_vec(),
diff --git a/src/validation/mod.rs b/src/validation/mod.rs
index 279ef13e..89e60082 100644
--- a/src/validation/mod.rs
+++ b/src/validation/mod.rs
@@ -89,7 +89,9 @@ pub fn check_rules(
     }
 
     if !ctx.errors.is_empty() {
-        return Err(Error::Rule { errors: ctx.errors });
+        return Err(Error::Rule {
+            errors: ctx.errors.into(),
+        });
     }
     Ok(CheckResult {
         cache_control,
diff --git a/src/validation/test_harness.rs b/src/validation/test_harness.rs
index 5f69c0c0..c4483ed9 100644
--- a/src/validation/test_harness.rs
+++ b/src/validation/test_harness.rs
@@ -355,7 +355,9 @@ where
     let mut visitor = factory();
     visit(&mut visitor, &mut ctx, doc);
     if !ctx.errors.is_empty() {
-        return Err(Error::Rule { errors: ctx.errors });
+        return Err(Error::Rule {
+            errors: ctx.errors.into(),
+        });
     }
     Ok(())
 }
diff --git a/tests/input_validators.rs b/tests/input_validators.rs
index 3613b331..e8bb7048 100644
--- a/tests/input_validators.rs
+++ b/tests/input_validators.rs
@@ -73,6 +73,7 @@ pub async fn test_input_validator_string_min_length() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -90,6 +91,7 @@ pub async fn test_input_validator_string_min_length() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -183,6 +185,7 @@ pub async fn test_input_validator_string_max_length() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -200,6 +203,7 @@ pub async fn test_input_validator_string_max_length() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -320,6 +324,7 @@ pub async fn test_input_validator_string_email() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -338,6 +343,7 @@ pub async fn test_input_validator_string_email() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -468,6 +474,7 @@ pub async fn test_input_validator_string_mac() {
                     }),
                     message: field_error_msg.clone()
                 })
+                .into()
             }
         );
 
@@ -486,6 +493,7 @@ pub async fn test_input_validator_string_mac() {
                     }),
                     message: object_error_msg.clone()
                 })
+                .into()
             }
         );
 
@@ -503,6 +511,7 @@ pub async fn test_input_validator_string_mac() {
                     }),
                     message: field_error_msg
                 })
+                .into()
             }
         );
 
@@ -521,6 +530,7 @@ pub async fn test_input_validator_string_mac() {
                     }),
                     message: object_error_msg
                 })
+                .into()
             }
         );
     }
@@ -578,6 +588,7 @@ pub async fn test_input_validator_string_mac() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -596,6 +607,7 @@ pub async fn test_input_validator_string_mac() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -637,6 +649,7 @@ pub async fn test_input_validator_string_mac() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -655,6 +668,7 @@ pub async fn test_input_validator_string_mac() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         }
@@ -715,6 +729,7 @@ pub async fn test_input_validator_int_range() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -732,6 +747,7 @@ pub async fn test_input_validator_int_range() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -820,6 +836,7 @@ pub async fn test_input_validator_int_less_than() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -837,6 +854,7 @@ pub async fn test_input_validator_int_less_than() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -927,6 +945,7 @@ pub async fn test_input_validator_int_greater_than() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -944,6 +963,7 @@ pub async fn test_input_validator_int_greater_than() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -1027,6 +1047,7 @@ pub async fn test_input_validator_int_nonzero() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -1044,6 +1065,7 @@ pub async fn test_input_validator_int_nonzero() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -1128,6 +1150,7 @@ pub async fn test_input_validator_int_equal() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -1145,6 +1168,7 @@ pub async fn test_input_validator_int_equal() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -1244,6 +1268,7 @@ pub async fn test_input_validator_list_max_length() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -1261,6 +1286,7 @@ pub async fn test_input_validator_list_max_length() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -1360,6 +1386,7 @@ pub async fn test_input_validator_list_min_length() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -1377,6 +1404,7 @@ pub async fn test_input_validator_list_min_length() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -1484,6 +1512,7 @@ pub async fn test_input_validator_operator_or() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -1501,6 +1530,7 @@ pub async fn test_input_validator_operator_or() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -1601,6 +1631,7 @@ pub async fn test_input_validator_operator_and() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -1618,6 +1649,7 @@ pub async fn test_input_validator_operator_and() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {
@@ -1724,6 +1756,7 @@ pub async fn test_input_validator_variable() {
                         }),
                         message: field_error_msg
                     })
+                    .into()
                 }
             );
 
@@ -1741,6 +1774,7 @@ pub async fn test_input_validator_variable() {
                         }),
                         message: object_error_msg
                     })
+                    .into()
                 }
             );
         } else {