diff --git a/api/src/v1/access.rs b/api/src/v1/access.rs
index 7b5ca189..2269eb43 100644
--- a/api/src/v1/access.rs
+++ b/api/src/v1/access.rs
@@ -163,8 +163,9 @@ pub struct AccessTokenInfo {
     pub expires_at: Option<OffsetDateTime>,
     /// Namespace streams based on the configured stream-level scope, which must be a prefix.
     /// Stream name arguments will be automatically prefixed, and the prefix will be stripped when listing streams.
-    #[cfg_attr(feature = "utoipa", schema(value_type = bool, default = false, required = false))]
-    pub auto_prefix_streams: Option<bool>,
+    #[serde(default)]
+    #[cfg_attr(feature = "utoipa", schema(default = false))]
+    pub auto_prefix_streams: bool,
     /// Access token scope.
     pub scope: AccessTokenScope,
 }
@@ -176,7 +177,7 @@ impl TryFrom<AccessTokenInfo> for types::access::IssueAccessTokenRequest {
         Ok(Self {
             id: value.id,
             expires_at: value.expires_at,
-            auto_prefix_streams: value.auto_prefix_streams.unwrap_or_default(),
+            auto_prefix_streams: value.auto_prefix_streams,
             scope: value.scope.try_into()?,
         })
     }
@@ -187,7 +188,7 @@ impl From<types::access::AccessTokenInfo> for AccessTokenInfo {
         Self {
             id: value.id,
             expires_at: Some(value.expires_at),
-            auto_prefix_streams: Some(value.auto_prefix_streams),
+            auto_prefix_streams: value.auto_prefix_streams,
             scope: value.scope.into(),
         }
     }
@@ -198,7 +199,7 @@ impl From<types::access::IssueAccessTokenRequest> for AccessTokenInfo {
         Self {
             id: value.id,
             expires_at: value.expires_at,
-            auto_prefix_streams: Some(value.auto_prefix_streams),
+            auto_prefix_streams: value.auto_prefix_streams,
             scope: value.scope.into(),
         }
     }
@@ -352,21 +353,20 @@ impl From<types::access::PermittedOperationGroups> for PermittedOperationGroups
 #[cfg_attr(feature = "utoipa", derive(utoipa::ToSchema))]
 pub struct ReadWritePermissions {
     /// Read permission.
-    #[cfg_attr(feature = "utoipa", schema(value_type = bool, default = false, required = false))]
-    pub read: Option<bool>,
+    #[serde(default)]
+    #[cfg_attr(feature = "utoipa", schema(default = false))]
+    pub read: bool,
     /// Write permission.
-    #[cfg_attr(feature = "utoipa", schema(value_type = bool, default = false, required = false))]
-    pub write: Option<bool>,
+    #[serde(default)]
+    #[cfg_attr(feature = "utoipa", schema(default = false))]
+    pub write: bool,
 }
 
 impl From<ReadWritePermissions> for types::access::ReadWritePermissions {
     fn from(value: ReadWritePermissions) -> Self {
         let ReadWritePermissions { read, write } = value;
 
-        Self {
-            read: read.unwrap_or_default(),
-            write: write.unwrap_or_default(),
-        }
+        Self { read, write }
     }
 }
 
@@ -374,10 +374,7 @@ impl From<types::access::ReadWritePermissions> for ReadWritePermissions {
     fn from(value: types::access::ReadWritePermissions) -> Self {
         let types::access::ReadWritePermissions { read, write } = value;
 
-        Self {
-            read: Some(read),
-            write: Some(write),
-        }
+        Self { read, write }
     }
 }
 
diff --git a/api/src/v1/config.rs b/api/src/v1/config.rs
index 3eeeadf6..004e9211 100644
--- a/api/src/v1/config.rs
+++ b/api/src/v1/config.rs
@@ -113,15 +113,17 @@ pub struct TimestampingConfig {
     /// Timestamping mode for appends that influences how timestamps are handled.
     pub mode: Option<TimestampingMode>,
     /// Allow client-specified timestamps to exceed the arrival time.
-    /// If this is `false` or not set, client timestamps will be capped at the arrival time.
-    pub uncapped: Option<bool>,
+    /// If this is `false`, client timestamps will be capped at the arrival time.
+    #[serde(default)]
+    #[cfg_attr(feature = "utoipa", schema(default = false))]
+    pub uncapped: bool,
 }
 
 impl TimestampingConfig {
     pub fn to_opt(config: types::config::OptionalTimestampingConfig) -> Option<Self> {
         let config = TimestampingConfig {
             mode: config.mode.map(Into::into),
-            uncapped: config.uncapped,
+            uncapped: config.uncapped.unwrap_or_default(),
         };
         if config == Self::default() {
             None
@@ -135,7 +137,7 @@ impl From<types::config::TimestampingConfig> for TimestampingConfig {
     fn from(value: types::config::TimestampingConfig) -> Self {
         Self {
             mode: Some(value.mode.into()),
-            uncapped: Some(value.uncapped),
+            uncapped: value.uncapped,
         }
     }
 }
@@ -144,7 +146,7 @@ impl From<TimestampingConfig> for types::config::OptionalTimestampingConfig {
     fn from(value: TimestampingConfig) -> Self {
         Self {
             mode: value.mode.map(Into::into),
-            uncapped: value.uncapped,
+            uncapped: Some(value.uncapped),
         }
     }
 }
@@ -160,14 +162,14 @@ pub struct TimestampingReconfiguration {
     /// Allow client-specified timestamps to exceed the arrival time.
     #[serde(default, skip_serializing_if = "Maybe::is_unspecified")]
     #[cfg_attr(feature = "utoipa", schema(value_type = Option<bool>))]
-    pub uncapped: Maybe<Option<bool>>,
+    pub uncapped: Maybe<bool>,
 }
 
 impl From<TimestampingReconfiguration> for types::config::TimestampingReconfiguration {
     fn from(value: TimestampingReconfiguration) -> Self {
         Self {
             mode: value.mode.map_opt(Into::into),
-            uncapped: value.uncapped,
+            uncapped: value.uncapped.map(Some),
         }
     }
 }
@@ -176,7 +178,7 @@ impl From<types::config::TimestampingReconfiguration> for TimestampingReconfigur
     fn from(value: types::config::TimestampingReconfiguration) -> Self {
         Self {
             mode: value.mode.map_opt(Into::into),
-            uncapped: value.uncapped,
+            uncapped: value.uncapped.map(|v| v.unwrap_or_default()),
         }
     }
 }
@@ -406,9 +408,11 @@ pub struct BasinConfig {
     pub default_stream_config: Option<StreamConfig>,
     /// Create stream on append if it doesn't exist, using the default stream configuration.
     #[serde(default)]
+    #[cfg_attr(feature = "utoipa", schema(default = false))]
     pub create_stream_on_append: bool,
     /// Create stream on read if it doesn't exist, using the default stream configuration.
     #[serde(default)]
+    #[cfg_attr(feature = "utoipa", schema(default = false))]
     pub create_stream_on_read: bool,
 }
 
@@ -527,10 +531,7 @@ mod tests {
     }
 
     fn gen_timestamping_config() -> impl Strategy<Value = TimestampingConfig> {
-        (
-            proptest::option::of(gen_timestamping_mode()),
-            proptest::option::of(any::<bool>()),
-        )
+        (proptest::option::of(gen_timestamping_mode()), any::<bool>())
             .prop_map(|(mode, uncapped)| TimestampingConfig { mode, uncapped })
     }
 
@@ -602,7 +603,13 @@ mod tests {
     }
 
     fn gen_timestamping_reconfiguration() -> impl Strategy<Value = TimestampingReconfiguration> {
-        (gen_maybe(gen_timestamping_mode()), gen_maybe(any::<bool>()))
+        (
+            gen_maybe(gen_timestamping_mode()),
+            prop_oneof![
+                Just(Maybe::Unspecified),
+                any::<bool>().prop_map(Maybe::Specified),
+            ],
+        )
             .prop_map(|(mode, uncapped)| TimestampingReconfiguration { mode, uncapped })
     }
 
diff --git a/sdk/src/types.rs b/sdk/src/types.rs
index aaa41a36..d5e38001 100644
--- a/sdk/src/types.rs
+++ b/sdk/src/types.rs
@@ -632,7 +632,7 @@ impl From<api::config::TimestampingConfig> for TimestampingConfig {
     fn from(value: api::config::TimestampingConfig) -> Self {
         Self {
             mode: value.mode.map(Into::into),
-            uncapped: value.uncapped.unwrap_or_default(),
+            uncapped: value.uncapped,
         }
     }
 }
@@ -641,7 +641,7 @@ impl From<TimestampingConfig> for api::config::TimestampingConfig {
     fn from(value: TimestampingConfig) -> Self {
         Self {
             mode: value.mode.map(Into::into),
-            uncapped: Some(value.uncapped),
+            uncapped: value.uncapped,
         }
     }
 }
@@ -1105,7 +1105,7 @@ pub struct TimestampingReconfiguration {
     /// Override for the existing [`mode`](TimestampingConfig::mode).
     pub mode: Maybe<Option<TimestampingMode>>,
     /// Override for the existing [`uncapped`](TimestampingConfig::uncapped) setting.
-    pub uncapped: Maybe<Option<bool>>,
+    pub uncapped: Maybe<bool>,
 }
 
 impl TimestampingReconfiguration {
@@ -1125,7 +1125,7 @@ impl TimestampingReconfiguration {
     /// Set the override for the existing [`uncapped`](TimestampingConfig::uncapped).
     pub fn with_uncapped(self, uncapped: bool) -> Self {
         Self {
-            uncapped: Maybe::Specified(Some(uncapped)),
+            uncapped: Maybe::Specified(uncapped),
             ..self
         }
     }
@@ -1430,7 +1430,7 @@ impl TryFrom<api::access::AccessTokenInfo> for AccessTokenInfo {
         Ok(Self {
             id: value.id,
             expires_at,
-            auto_prefix_streams: value.auto_prefix_streams.unwrap_or(false),
+            auto_prefix_streams: value.auto_prefix_streams,
             scope: value.scope.into(),
         })
     }
@@ -1523,8 +1523,8 @@ impl ReadWritePermissions {
 impl From<ReadWritePermissions> for api::access::ReadWritePermissions {
     fn from(value: ReadWritePermissions) -> Self {
         Self {
-            read: Some(value.read),
-            write: Some(value.write),
+            read: value.read,
+            write: value.write,
         }
     }
 }
@@ -1532,8 +1532,8 @@ impl From<ReadWritePermissions> for api::access::ReadWritePermissions {
 impl From<api::access::ReadWritePermissions> for ReadWritePermissions {
     fn from(value: api::access::ReadWritePermissions) -> Self {
         Self {
-            read: value.read.unwrap_or_default(),
-            write: value.write.unwrap_or_default(),
+            read: value.read,
+            write: value.write,
         }
     }
 }
@@ -1980,7 +1980,7 @@ impl From<IssueAccessTokenInput> for api::access::AccessTokenInfo {
         Self {
             id: value.id,
             expires_at: value.expires_at.map(Into::into),
-            auto_prefix_streams: value.auto_prefix_streams.then_some(true),
+            auto_prefix_streams: value.auto_prefix_streams,
             scope: value.scope.into(),
         }
     }