diff --git a/CHANGELOG.md b/CHANGELOG.md
index 7380a84942..69f847e66e 100644
--- a/CHANGELOG.md
+++ b/CHANGELOG.md
@@ -7,6 +7,7 @@ and this project adheres to [Semantic Versioning](https://semver.org/spec/v2.0.0
 ## [Unreleased]
 
 ### Changed
+- Use name-only syntax for `anonymous` ink! event item configuration argument - [#2140](https://github.com/paritytech/ink/pull/2140)
 - Restrict syntax for setting default ink! e2e test runtime-only emulator - [#2143](https://github.com/paritytech/ink/pull/2143)
 
 ## Version 5.0.0-rc.2
diff --git a/crates/ink/ir/src/ast/attr_args.rs b/crates/ink/ir/src/ast/attr_args.rs
index ba8d598b2c..6ed96c2571 100644
--- a/crates/ink/ir/src/ast/attr_args.rs
+++ b/crates/ink/ir/src/ast/attr_args.rs
@@ -12,7 +12,7 @@
 // See the License for the specific language governing permissions and
 // limitations under the License.
 
-use super::MetaNameValue;
+use super::Meta;
 use syn::{
     parse::{
         Parse,
@@ -28,7 +28,7 @@ use syn::{
 /// in `#[ink::contract(env = ::my::env::Environment)]`.
 #[derive(Clone, Debug, PartialEq, Eq)]
 pub struct AttributeArgs {
-    args: Punctuated<MetaNameValue, Token![,]>,
+    args: Punctuated<Meta, Token![,]>,
 }
 
 impl quote::ToTokens for AttributeArgs {
@@ -38,8 +38,8 @@ impl quote::ToTokens for AttributeArgs {
 }
 
 impl IntoIterator for AttributeArgs {
-    type Item = MetaNameValue;
-    type IntoIter = syn::punctuated::IntoIter<MetaNameValue>;
+    type Item = Meta;
+    type IntoIter = syn::punctuated::IntoIter<Meta>;
 
     fn into_iter(self) -> Self::IntoIter {
         self.args.into_iter()
@@ -57,14 +57,17 @@ impl Parse for AttributeArgs {
 #[cfg(test)]
 mod tests {
     use super::*;
-    use crate::ast::MetaValue;
+    use crate::ast::{
+        MetaNameValue,
+        MetaValue,
+    };
     use quote::quote;
 
     impl AttributeArgs {
         /// Creates a new attribute argument list from the given arguments.
         pub fn new<I>(args: I) -> Self
         where
-            I: IntoIterator<Item = MetaNameValue>,
+            I: IntoIterator<Item = Meta>,
         {
             Self {
                 args: args.into_iter().collect(),
@@ -80,15 +83,23 @@ mod tests {
         )
     }
 
+    #[test]
+    fn flag_works() {
+        assert_eq!(
+            syn::parse2::<AttributeArgs>(quote! { flag }).unwrap(),
+            AttributeArgs::new(vec![Meta::Path(syn::parse_quote! { flag })])
+        )
+    }
+
     #[test]
     fn literal_bool_value_works() {
         assert_eq!(
             syn::parse2::<AttributeArgs>(quote! { name = true }).unwrap(),
-            AttributeArgs::new(vec![MetaNameValue {
+            AttributeArgs::new(vec![Meta::NameValue(MetaNameValue {
                 name: syn::parse_quote! { name },
                 eq_token: syn::parse_quote! { = },
                 value: MetaValue::Lit(syn::parse_quote! { true }),
-            }])
+            })])
         )
     }
 
@@ -96,11 +107,11 @@ mod tests {
     fn literal_str_value_works() {
         assert_eq!(
             syn::parse2::<AttributeArgs>(quote! { name = "string literal" }).unwrap(),
-            AttributeArgs::new(vec![MetaNameValue {
+            AttributeArgs::new(vec![Meta::NameValue(MetaNameValue {
                 name: syn::parse_quote! { name },
                 eq_token: syn::parse_quote! { = },
                 value: MetaValue::Lit(syn::parse_quote! { "string literal" }),
-            }])
+            })])
         )
     }
 
@@ -108,11 +119,11 @@ mod tests {
     fn ident_value_works() {
         assert_eq!(
             syn::parse2::<AttributeArgs>(quote! { name = MyIdentifier }).unwrap(),
-            AttributeArgs::new(vec![MetaNameValue {
+            AttributeArgs::new(vec![Meta::NameValue(MetaNameValue {
                 name: syn::parse_quote! { name },
                 eq_token: syn::parse_quote! { = },
                 value: MetaValue::Path(syn::parse_quote! { MyIdentifier }),
-            }])
+            })])
         )
     }
 
@@ -120,11 +131,11 @@ mod tests {
     fn root_path_value_works() {
         assert_eq!(
             syn::parse2::<AttributeArgs>(quote! { name = ::this::is::my::Path }).unwrap(),
-            AttributeArgs::new(vec![MetaNameValue {
+            AttributeArgs::new(vec![Meta::NameValue(MetaNameValue {
                 name: syn::parse_quote! { name },
                 eq_token: syn::parse_quote! { = },
                 value: MetaValue::Path(syn::parse_quote! { ::this::is::my::Path }),
-            }])
+            })])
         )
     }
 
@@ -133,24 +144,24 @@ mod tests {
         assert_eq!(
             syn::parse2::<AttributeArgs>(quote! { name = this::is::my::relative::Path })
                 .unwrap(),
-            AttributeArgs::new(vec![MetaNameValue {
+            AttributeArgs::new(vec![Meta::NameValue(MetaNameValue {
                 name: syn::parse_quote! { name },
                 eq_token: syn::parse_quote! { = },
                 value: MetaValue::Path(
                     syn::parse_quote! { this::is::my::relative::Path }
                 ),
-            }])
+            })])
         )
     }
 
     #[test]
     fn trailing_comma_works() {
         let mut expected_args = Punctuated::new();
-        expected_args.push_value(MetaNameValue {
+        expected_args.push_value(Meta::NameValue(MetaNameValue {
             name: syn::parse_quote! { name },
             eq_token: syn::parse_quote! { = },
             value: MetaValue::Path(syn::parse_quote! { value }),
-        });
+        }));
         expected_args.push_punct(<Token![,]>::default());
         assert_eq!(
             syn::parse2::<AttributeArgs>(quote! { name = value, }).unwrap(),
@@ -164,6 +175,7 @@ mod tests {
     fn many_mixed_works() {
         assert_eq!(
             syn::parse2::<AttributeArgs>(quote! {
+                flag,
                 name1 = ::root::Path,
                 name2 = false,
                 name3 = "string literal",
@@ -172,31 +184,32 @@ mod tests {
             })
             .unwrap(),
             AttributeArgs::new(vec![
-                MetaNameValue {
+                Meta::Path(syn::parse_quote! { flag }),
+                Meta::NameValue(MetaNameValue {
                     name: syn::parse_quote! { name1 },
                     eq_token: syn::parse_quote! { = },
                     value: MetaValue::Path(syn::parse_quote! { ::root::Path }),
-                },
-                MetaNameValue {
+                }),
+                Meta::NameValue(MetaNameValue {
                     name: syn::parse_quote! { name2 },
                     eq_token: syn::parse_quote! { = },
                     value: MetaValue::Lit(syn::parse_quote! { false }),
-                },
-                MetaNameValue {
+                }),
+                Meta::NameValue(MetaNameValue {
                     name: syn::parse_quote! { name3 },
                     eq_token: syn::parse_quote! { = },
                     value: MetaValue::Lit(syn::parse_quote! { "string literal" }),
-                },
-                MetaNameValue {
+                }),
+                Meta::NameValue(MetaNameValue {
                     name: syn::parse_quote! { name4 },
                     eq_token: syn::parse_quote! { = },
                     value: MetaValue::Lit(syn::parse_quote! { 42 }),
-                },
-                MetaNameValue {
+                }),
+                Meta::NameValue(MetaNameValue {
                     name: syn::parse_quote! { name5 },
                     eq_token: syn::parse_quote! { = },
                     value: MetaValue::Lit(syn::parse_quote! { 7.7 }),
-                },
+                }),
             ])
         )
     }
diff --git a/crates/ink/ir/src/ast/meta.rs b/crates/ink/ir/src/ast/meta.rs
index df1703afa9..831b00e954 100644
--- a/crates/ink/ir/src/ast/meta.rs
+++ b/crates/ink/ir/src/ast/meta.rs
@@ -25,7 +25,9 @@ use syn::{
     },
     punctuated::Punctuated,
     spanned::Spanned,
+    LitBool,
     LitInt,
+    LitStr,
     Token,
 };
 
@@ -62,6 +64,32 @@ impl ToTokens for Meta {
     }
 }
 
+impl Meta {
+    /// Returns the meta-item name.
+    pub fn name(&self) -> &syn::Path {
+        match self {
+            Meta::Path(path) => path,
+            Meta::NameValue(name_value) => &name_value.name,
+        }
+    }
+
+    /// Returns the meta-item value (if any).
+    pub fn value(&self) -> Option<&MetaValue> {
+        match self {
+            Meta::Path(_) => None,
+            Meta::NameValue(name_value) => Some(&name_value.value),
+        }
+    }
+
+    /// Returns the `NameValue` variant (if any).
+    pub fn name_value(&self) -> Option<&MetaNameValue> {
+        match self {
+            Meta::NameValue(name_value) => Some(name_value),
+            Meta::Path(_) => None,
+        }
+    }
+}
+
 /// A name-value pair within an attribute, like `feature = "nightly"`.
 ///
 /// The only difference from `syn::MetaNameValue` is that this additionally
@@ -157,13 +185,37 @@ impl MetaValue {
         }
     }
 
-    /// Returns the the literal if it is an integer literal.
+    /// Returns the literal if it is an integer literal.
     pub fn as_lit_int(&self) -> Option<&LitInt> {
         match self {
             Self::Lit(syn::Lit::Int(lit_int)) => Some(lit_int),
             _ => None,
         }
     }
+
+    /// Returns the literal if it is a boolean literal.
+    pub fn as_lit_bool(&self) -> Option<&LitBool> {
+        match self {
+            Self::Lit(syn::Lit::Bool(lit_bool)) => Some(lit_bool),
+            _ => None,
+        }
+    }
+
+    /// Returns the literal if it is a string literal.
+    pub fn as_lit_string(&self) -> Option<&LitStr> {
+        match self {
+            Self::Lit(syn::Lit::Str(lit_str)) => Some(lit_str),
+            _ => None,
+        }
+    }
+
+    /// Returns the path (if the value is a path).
+    pub fn as_path(&self) -> Option<&syn::Path> {
+        match self {
+            Self::Path(path) => Some(path),
+            _ => None,
+        }
+    }
 }
 
 #[derive(Debug, Clone, PartialEq, Eq, Hash)]
@@ -243,4 +295,16 @@ mod tests {
             })
         )
     }
+
+    #[test]
+    fn at_token_works() {
+        assert_eq!(
+            syn::parse2::<Meta>(quote! { selector = @ }).unwrap(),
+            Meta::NameValue(MetaNameValue {
+                name: syn::parse_quote! { selector },
+                eq_token: syn::parse_quote! { = },
+                value: MetaValue::Symbol(Symbol::AtSign(syn::parse_quote! { @ })),
+            })
+        )
+    }
 }
diff --git a/crates/ink/ir/src/error.rs b/crates/ink/ir/src/error.rs
index a955dc2e10..55fd1ef5f7 100644
--- a/crates/ink/ir/src/error.rs
+++ b/crates/ink/ir/src/error.rs
@@ -53,6 +53,21 @@ macro_rules! format_err_spanned {
     }
 }
 
+/// Creates a [`syn::Error`] with the format message and infers the
+/// [`Span`](`proc_macro2::Span`) using the [`ToTokens`](`quote::ToTokens`) implementation
+/// for the [`MetaValue`][crate::ast::MetaValue] (if possible).
+///
+/// See [`format_err_spanned`] for more details.
+macro_rules! format_err_spanned_value {
+    ($arg:expr, $($msg:tt)*) => {
+        if let Some(value) = $arg.value() {
+            format_err_spanned!(value, $($msg)*)
+        } else {
+            format_err_spanned!($arg, $($msg)*)
+        }
+    };
+}
+
 /// Creates a [`syn::Error`] with the format message and infers the
 /// [`Span`](`proc_macro2::Span`) using [`Spanned`](`syn::spanned::Spanned`).
 ///
diff --git a/crates/ink/ir/src/ir/chain_extension.rs b/crates/ink/ir/src/ir/chain_extension.rs
index 30e5b768ec..f4e2272709 100644
--- a/crates/ink/ir/src/ir/chain_extension.rs
+++ b/crates/ink/ir/src/ir/chain_extension.rs
@@ -81,15 +81,15 @@ impl TryFrom<ast::AttributeArgs> for Config {
         let mut ext_id: Option<ExtensionId> = None;
 
         for arg in args.clone().into_iter() {
-            if arg.name.is_ident("extension") {
+            if arg.name().is_ident("extension") {
                 if ext_id.is_some() {
-                    return Err(format_err_spanned!(
-                        arg.value,
+                    return Err(format_err_spanned_value!(
+                        arg,
                         "encountered duplicate ink! contract `extension` configuration argument",
-                    ))
+                    ));
                 }
 
-                if let Some(lit_int) = arg.value.as_lit_int() {
+                if let Some(lit_int) = arg.value().and_then(ast::MetaValue::as_lit_int) {
                     let id = lit_int.base10_parse::<u16>()
                         .map_err(|error| {
                             format_err_spanned!(
@@ -98,16 +98,16 @@ impl TryFrom<ast::AttributeArgs> for Config {
                         })?;
                     ext_id = Some(ExtensionId::from_u16(id));
                 } else {
-                    return Err(format_err_spanned!(
-                        arg.value,
+                    return Err(format_err_spanned_value!(
+                        arg,
                         "expected `u16` integer type for `N` in `extension = N`",
-                    ))
+                    ));
                 }
             } else {
                 return Err(format_err_spanned!(
                     arg,
                     "encountered unknown or unsupported chain extension configuration argument",
-                ))
+                ));
             }
         }
 
diff --git a/crates/ink/ir/src/ir/config.rs b/crates/ink/ir/src/ir/config.rs
index 2e5d7a7340..dbb63bf232 100644
--- a/crates/ink/ir/src/ir/config.rs
+++ b/crates/ink/ir/src/ir/config.rs
@@ -41,25 +41,35 @@ impl TryFrom<ast::AttributeArgs> for Config {
         let mut whitelisted_attributes = WhitelistedAttributes::default();
 
         for arg in args.into_iter() {
-            if arg.name.is_ident("env") {
+            if arg.name().is_ident("env") {
                 if let Some((_, ast)) = env {
-                    return Err(duplicate_config_err(ast, arg, "env", "contract"))
+                    return Err(duplicate_config_err(ast, arg, "env", "contract"));
                 }
-                if let ast::MetaValue::Path(path) = &arg.value {
-                    env = Some((Environment { path: path.clone() }, arg))
+                let env_info = arg
+                    .name_value()
+                    .zip(arg.value().and_then(ast::MetaValue::as_path));
+                if let Some((name_value, path)) = env_info {
+                    env = Some((Environment { path: path.clone() }, name_value.clone()))
                 } else {
                     return Err(format_err_spanned!(
                         arg,
-                        "expected a path for `env` ink! configuration argument",
-                    ))
+                        "expected a path value for `env` ink! configuration argument",
+                    ));
+                }
+            } else if arg.name().is_ident("keep_attr") {
+                if let Some(name_value) = arg.name_value() {
+                    whitelisted_attributes.parse_arg_value(name_value)?;
+                } else {
+                    return Err(format_err_spanned!(
+                        arg,
+                        "expected a string literal value for `keep_attr` ink! configuration argument",
+                    ));
                 }
-            } else if arg.name.is_ident("keep_attr") {
-                whitelisted_attributes.parse_arg_value(&arg)?;
             } else {
                 return Err(format_err_spanned!(
                     arg,
                     "encountered unknown or unsupported ink! configuration argument",
-                ))
+                ));
             }
         }
         Ok(Config {
@@ -143,7 +153,15 @@ mod tests {
     fn env_invalid_value_fails() {
         assert_try_from(
             syn::parse_quote! { env = "invalid" },
-            Err("expected a path for `env` ink! configuration argument"),
+            Err("expected a path value for `env` ink! configuration argument"),
+        );
+    }
+
+    #[test]
+    fn env_missing_value_fails() {
+        assert_try_from(
+            syn::parse_quote! { env },
+            Err("expected a path value for `env` ink! configuration argument"),
         );
     }
 
@@ -189,4 +207,12 @@ mod tests {
             Err("expected a string with attributes separated by `,`"),
         );
     }
+
+    #[test]
+    fn keep_attr_missing_value_fails() {
+        assert_try_from(
+            syn::parse_quote! { keep_attr },
+            Err("expected a string literal value for `keep_attr` ink! configuration argument"),
+        );
+    }
 }
diff --git a/crates/ink/ir/src/ir/event/config.rs b/crates/ink/ir/src/ir/event/config.rs
index 71313c3653..1020bd8657 100644
--- a/crates/ink/ir/src/ir/event/config.rs
+++ b/crates/ink/ir/src/ir/event/config.rs
@@ -33,22 +33,23 @@ impl TryFrom<ast::AttributeArgs> for EventConfig {
     type Error = syn::Error;
 
     fn try_from(args: ast::AttributeArgs) -> Result<Self, Self::Error> {
-        let mut anonymous: Option<syn::LitBool> = None;
+        let mut anonymous: Option<syn::Path> = None;
         let mut signature_topic: Option<syn::LitStr> = None;
         for arg in args.into_iter() {
-            if arg.name.is_ident("anonymous") {
+            if arg.name().is_ident("anonymous") {
                 if let Some(lit_bool) = anonymous {
                     return Err(duplicate_config_err(lit_bool, arg, "anonymous", "event"));
                 }
-                if let ast::MetaValue::Lit(syn::Lit::Bool(lit_bool)) = &arg.value {
-                    anonymous = Some(lit_bool.clone())
+                if let ast::Meta::Path(path) = arg {
+                    anonymous = Some(path)
                 } else {
                     return Err(format_err_spanned!(
                         arg,
-                        "expected a bool literal for `anonymous` ink! event item configuration argument",
+                        "encountered an unexpected value for `anonymous` ink! event item configuration argument. \
+                        Did you mean #[ink::event(anonymous)] ?",
                     ));
                 }
-            } else if arg.name.is_ident("signature_topic") {
+            } else if arg.name().is_ident("signature_topic") {
                 if anonymous.is_some() {
                     return Err(format_err_spanned!(
                         arg,
@@ -57,14 +58,20 @@ impl TryFrom<ast::AttributeArgs> for EventConfig {
                 }
 
                 if let Some(lit_str) = signature_topic {
-                    return Err(duplicate_config_err(lit_str, arg, "anonymous", "event"));
+                    return Err(duplicate_config_err(
+                        lit_str,
+                        arg,
+                        "signature_topic",
+                        "event",
+                    ));
                 }
-                if let ast::MetaValue::Lit(syn::Lit::Str(lis_str)) = &arg.value {
-                    signature_topic = Some(lis_str.clone())
+                if let Some(lit_str) = arg.value().and_then(ast::MetaValue::as_lit_string)
+                {
+                    signature_topic = Some(lit_str.clone())
                 } else {
                     return Err(format_err_spanned!(
                         arg,
-                        "expected a bool literal for `anonymous` ink! event item configuration argument",
+                        "expected a string literal value for `signature_topic` ink! event item configuration argument",
                     ));
                 }
             } else {
@@ -76,7 +83,7 @@ impl TryFrom<ast::AttributeArgs> for EventConfig {
         }
 
         Ok(EventConfig::new(
-            anonymous.map(|lit_bool| lit_bool.value).unwrap_or(false),
+            anonymous.is_some(),
             signature_topic.map(|lit_str| lit_str.value()),
         ))
     }
diff --git a/crates/ink/ir/src/ir/event/signature_topic.rs b/crates/ink/ir/src/ir/event/signature_topic.rs
index 4e4aa4d46f..49ed14fdd2 100644
--- a/crates/ink/ir/src/ir/event/signature_topic.rs
+++ b/crates/ink/ir/src/ir/event/signature_topic.rs
@@ -89,14 +89,15 @@ impl TryFrom<ast::AttributeArgs> for Option<SignatureTopicArg> {
     fn try_from(args: ast::AttributeArgs) -> Result<Self, Self::Error> {
         let mut signature_topic: Option<SignatureTopicArg> = None;
         for arg in args.into_iter() {
-            if arg.name.is_ident("hash") {
+            if arg.name().is_ident("hash") {
                 if signature_topic.is_some() {
                     return Err(format_err!(
                         arg.span(),
                         "encountered duplicate ink! event configuration argument"
                     ));
                 }
-                signature_topic = Some(SignatureTopicArg::try_from(&arg.value)?);
+                signature_topic =
+                    arg.value().map(SignatureTopicArg::try_from).transpose()?;
             } else {
                 return Err(format_err_spanned!(
                     arg,
diff --git a/crates/ink/ir/src/ir/storage_item/config.rs b/crates/ink/ir/src/ir/storage_item/config.rs
index 213a5e77a1..d35c984c45 100644
--- a/crates/ink/ir/src/ir/storage_item/config.rs
+++ b/crates/ink/ir/src/ir/storage_item/config.rs
@@ -33,21 +33,22 @@ impl TryFrom<ast::AttributeArgs> for StorageItemConfig {
     fn try_from(args: ast::AttributeArgs) -> Result<Self, Self::Error> {
         let mut derive: Option<syn::LitBool> = None;
         for arg in args.into_iter() {
-            if arg.name.is_ident("derive") {
+            if arg.name().is_ident("derive") {
                 if let Some(lit_bool) = derive {
                     return Err(duplicate_config_err(
                         lit_bool,
                         arg,
                         "derive",
                         "storage item",
-                    ))
+                    ));
                 }
-                if let ast::MetaValue::Lit(syn::Lit::Bool(lit_bool)) = &arg.value {
+                if let Some(lit_bool) = arg.value().and_then(ast::MetaValue::as_lit_bool)
+                {
                     derive = Some(lit_bool.clone())
                 } else {
                     return Err(format_err_spanned!(
                         arg,
-                        "expected a bool literal for `derive` ink! storage item configuration argument",
+                        "expected a bool literal value for `derive` ink! storage item configuration argument",
                     ));
                 }
             } else {
diff --git a/crates/ink/ir/src/ir/trait_def/config.rs b/crates/ink/ir/src/ir/trait_def/config.rs
index 1e6ae16274..4b4737179f 100644
--- a/crates/ink/ir/src/ir/trait_def/config.rs
+++ b/crates/ink/ir/src/ir/trait_def/config.rs
@@ -57,31 +57,41 @@ impl TryFrom<ast::AttributeArgs> for TraitDefinitionConfig {
         let mut namespace: Option<(syn::LitStr, ast::MetaNameValue)> = None;
         let mut whitelisted_attributes = WhitelistedAttributes::default();
         for arg in args.into_iter() {
-            if arg.name.is_ident("namespace") {
+            if arg.name().is_ident("namespace") {
                 if let Some((_, meta_name_value)) = namespace {
                     return Err(duplicate_config_err(
                         meta_name_value,
                         arg,
                         "namespace",
                         "trait definition",
-                    ))
+                    ));
                 }
-                if let ast::MetaValue::Lit(syn::Lit::Str(lit_str)) = &arg.value {
+                let namespace_info = arg
+                    .name_value()
+                    .zip(arg.value().and_then(ast::MetaValue::as_lit_string));
+                if let Some((name_value, lit_str)) = namespace_info {
                     if syn::parse_str::<syn::Ident>(&lit_str.value()).is_err() {
                         return Err(format_err_spanned!(
                             lit_str,
                             "encountered invalid Rust identifier for the ink! namespace configuration parameter"
                         ));
                     }
-                    namespace = Some((lit_str.clone(), arg))
+                    namespace = Some((lit_str.clone(), name_value.clone()))
+                } else {
+                    return Err(format_err_spanned!(
+                        arg,
+                        "expected a string literal value for `namespace` ink! trait definition configuration argument",
+                    ));
+                }
+            } else if arg.name().is_ident("keep_attr") {
+                if let Some(name_value) = arg.name_value() {
+                    whitelisted_attributes.parse_arg_value(name_value)?;
                 } else {
                     return Err(format_err_spanned!(
                         arg,
-                        "expected a string literal for `namespace` ink! trait definition configuration argument",
+                        "expected a string literal value for `keep_attr` ink! configuration argument",
                     ));
                 }
-            } else if arg.name.is_ident("keep_attr") {
-                whitelisted_attributes.parse_arg_value(&arg)?;
             } else {
                 return Err(format_err_spanned!(
                     arg,
diff --git a/crates/ink/macro/src/lib.rs b/crates/ink/macro/src/lib.rs
index 6476b0ef92..b81473af2c 100644
--- a/crates/ink/macro/src/lib.rs
+++ b/crates/ink/macro/src/lib.rs
@@ -657,7 +657,7 @@ pub fn trait_definition(attr: TokenStream, item: TokenStream) -> TokenStream {
 /// contract.
 ///
 /// By default, a signature topic will be generated for the event. This allows consumers
-/// to filter and identify events of this type. Marking an event with `anonymous = true`
+/// to filter and identify events of this type. Marking an event with `anonymous`
 /// means no signature topic will be generated or emitted.
 /// Custom signature topic can be specified with `signature_topic = <32 byte hex string>`.
 ///
@@ -673,8 +673,8 @@ pub fn trait_definition(attr: TokenStream, item: TokenStream) -> TokenStream {
 ///     pub topic: [u8; 32],
 /// }
 ///
-/// // Setting `anonymous = true` means no signature topic will be emitted for the event.
-/// #[ink::event(anonymous = true)]
+/// // Setting `anonymous` means no signature topic will be emitted for the event.
+/// #[ink::event(anonymous)]
 /// pub struct MyAnonEvent {
 ///     pub field: u32,
 ///     #[ink(topic)]
diff --git a/crates/ink/tests/ui/contract/fail/config-keep-attr-missing-arg.stderr b/crates/ink/tests/ui/contract/fail/config-keep-attr-missing-arg.stderr
index ec0956fac8..33054b2fcb 100644
--- a/crates/ink/tests/ui/contract/fail/config-keep-attr-missing-arg.stderr
+++ b/crates/ink/tests/ui/contract/fail/config-keep-attr-missing-arg.stderr
@@ -1,4 +1,4 @@
-error: ink! config options require an argument separated by '='
+error: expected a string literal value for `keep_attr` ink! configuration argument
  --> tests/ui/contract/fail/config-keep-attr-missing-arg.rs:1:17
   |
 1 | #[ink::contract(keep_attr)]
diff --git a/crates/ink/tests/ui/event/fail/anonymous_invalid_value.rs b/crates/ink/tests/ui/event/fail/anonymous_invalid_value.rs
new file mode 100644
index 0000000000..a1dcb8abbc
--- /dev/null
+++ b/crates/ink/tests/ui/event/fail/anonymous_invalid_value.rs
@@ -0,0 +1,8 @@
+#[ink::event(anonymous = true)]
+pub struct Event {
+    #[ink(topic)]
+    pub topic: [u8; 32],
+    pub field_1: u32,
+}
+
+fn main() {}
diff --git a/crates/ink/tests/ui/event/fail/anonymous_invalid_value.stderr b/crates/ink/tests/ui/event/fail/anonymous_invalid_value.stderr
new file mode 100644
index 0000000000..6547f3ac27
--- /dev/null
+++ b/crates/ink/tests/ui/event/fail/anonymous_invalid_value.stderr
@@ -0,0 +1,5 @@
+error: encountered an unexpected value for `anonymous` ink! event item configuration argument. Did you mean #[ink::event(anonymous)] ?
+ --> tests/ui/event/fail/anonymous_invalid_value.rs:1:14
+  |
+1 | #[ink::event(anonymous = true)]
+  |              ^^^^^^^^^^^^^^^^
diff --git a/crates/ink/tests/ui/event/fail/signature_missing_value.rs b/crates/ink/tests/ui/event/fail/signature_missing_value.rs
new file mode 100644
index 0000000000..293e2d50d6
--- /dev/null
+++ b/crates/ink/tests/ui/event/fail/signature_missing_value.rs
@@ -0,0 +1,6 @@
+#[ink::event(signature_topic)]
+pub struct Event {
+    pub topic: [u8; 32],
+}
+
+fn main() {}
diff --git a/crates/ink/tests/ui/event/fail/signature_missing_value.stderr b/crates/ink/tests/ui/event/fail/signature_missing_value.stderr
new file mode 100644
index 0000000000..a81245df5d
--- /dev/null
+++ b/crates/ink/tests/ui/event/fail/signature_missing_value.stderr
@@ -0,0 +1,5 @@
+error: expected a string literal value for `signature_topic` ink! event item configuration argument
+ --> tests/ui/event/fail/signature_missing_value.rs:1:14
+  |
+1 | #[ink::event(signature_topic)]
+  |              ^^^^^^^^^^^^^^^
diff --git a/crates/ink/tests/ui/event/pass/anonymous_flag_works.rs b/crates/ink/tests/ui/event/pass/anonymous_flag_works.rs
index 34a6e705d2..edf81c79b9 100644
--- a/crates/ink/tests/ui/event/pass/anonymous_flag_works.rs
+++ b/crates/ink/tests/ui/event/pass/anonymous_flag_works.rs
@@ -1,8 +1,8 @@
-#[ink::event(anonymous = true)]
+#[ink::event(anonymous)]
 pub struct Event {
     #[ink(topic)]
     pub topic: [u8; 32],
     pub field_1: u32,
 }
 
-fn main() {}
\ No newline at end of file
+fn main() {}
diff --git a/crates/ink/tests/ui/storage_item/fail/argument_derive_invalid_type.stderr b/crates/ink/tests/ui/storage_item/fail/argument_derive_invalid_type.stderr
index 40fd498c21..cb8a6edcb9 100644
--- a/crates/ink/tests/ui/storage_item/fail/argument_derive_invalid_type.stderr
+++ b/crates/ink/tests/ui/storage_item/fail/argument_derive_invalid_type.stderr
@@ -1,4 +1,4 @@
-error: expected a bool literal for `derive` ink! storage item configuration argument
+error: expected a bool literal value for `derive` ink! storage item configuration argument
  --> tests/ui/storage_item/fail/argument_derive_invalid_type.rs:1:21
   |
 1 | #[ink::storage_item(derive = "false")]
diff --git a/crates/ink/tests/ui/storage_item/fail/argument_derive_missing_arg.stderr b/crates/ink/tests/ui/storage_item/fail/argument_derive_missing_arg.stderr
index 1915baf6c6..3c5f9c4153 100644
--- a/crates/ink/tests/ui/storage_item/fail/argument_derive_missing_arg.stderr
+++ b/crates/ink/tests/ui/storage_item/fail/argument_derive_missing_arg.stderr
@@ -1,4 +1,4 @@
-error: ink! config options require an argument separated by '='
+error: expected a bool literal value for `derive` ink! storage item configuration argument
  --> tests/ui/storage_item/fail/argument_derive_missing_arg.rs:1:21
   |
 1 | #[ink::storage_item(derive)]
diff --git a/crates/ink/tests/ui/trait_def/fail/config_keep_attr_missing_arg.stderr b/crates/ink/tests/ui/trait_def/fail/config_keep_attr_missing_arg.stderr
index 6b9d883a1b..0aea620055 100644
--- a/crates/ink/tests/ui/trait_def/fail/config_keep_attr_missing_arg.stderr
+++ b/crates/ink/tests/ui/trait_def/fail/config_keep_attr_missing_arg.stderr
@@ -1,4 +1,4 @@
-error: ink! config options require an argument separated by '='
+error: expected a string literal value for `keep_attr` ink! configuration argument
  --> tests/ui/trait_def/fail/config_keep_attr_missing_arg.rs:1:25
   |
 1 | #[ink::trait_definition(keep_attr)]
diff --git a/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_2.stderr b/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_2.stderr
index d0db5ea758..1a125cc230 100644
--- a/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_2.stderr
+++ b/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_2.stderr
@@ -1,4 +1,4 @@
-error: ink! config options require an argument separated by '='
+error: expected a string literal value for `namespace` ink! trait definition configuration argument
  --> tests/ui/trait_def/fail/config_namespace_invalid_2.rs:1:25
   |
 1 | #[ink::trait_definition(namespace)]
diff --git a/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_4.stderr b/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_4.stderr
index a609223a57..196a49e75d 100644
--- a/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_4.stderr
+++ b/crates/ink/tests/ui/trait_def/fail/config_namespace_invalid_4.stderr
@@ -1,4 +1,4 @@
-error: expected a string literal for `namespace` ink! trait definition configuration argument
+error: expected a string literal value for `namespace` ink! trait definition configuration argument
  --> tests/ui/trait_def/fail/config_namespace_invalid_4.rs:1:25
   |
 1 | #[ink::trait_definition(namespace = true)]
diff --git a/integration-tests/events/lib.rs b/integration-tests/events/lib.rs
index 8fcaace02a..211b55b33a 100644
--- a/integration-tests/events/lib.rs
+++ b/integration-tests/events/lib.rs
@@ -1,6 +1,6 @@
 #![cfg_attr(not(feature = "std"), no_std, no_main)]
 
-#[ink::event(anonymous = true)]
+#[ink::event(anonymous)]
 pub struct AnonymousEvent {
     #[ink(topic)]
     pub topic: [u8; 32],