diff --git a/README.md b/README.md
index e6a26f64..3a4b49af 100644
--- a/README.md
+++ b/README.md
@@ -51,8 +51,7 @@ import org.onebusaway.models.CurrentTimeRetrieveResponse
 // Configures using the `ONEBUSAWAY_API_KEY` environment variable
 val client: OnebusawaySdkClient = OnebusawaySdkOkHttpClient.fromEnv()
 
-val params: CurrentTimeRetrieveParams = CurrentTimeRetrieveParams.builder().build()
-val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve(params)
+val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve()
 ```
 
 ## Client configuration
@@ -128,8 +127,7 @@ import org.onebusaway.models.CurrentTimeRetrieveResponse
 // Configures using the `ONEBUSAWAY_API_KEY` environment variable
 val client: OnebusawaySdkClient = OnebusawaySdkOkHttpClient.fromEnv()
 
-val params: CurrentTimeRetrieveParams = CurrentTimeRetrieveParams.builder().build()
-val currentTime: CurrentTimeRetrieveResponse = client.async().currentTime().retrieve(params)
+val currentTime: CurrentTimeRetrieveResponse = client.async().currentTime().retrieve()
 ```
 
 Or create an asynchronous client from the beginning:
@@ -143,8 +141,7 @@ import org.onebusaway.models.CurrentTimeRetrieveResponse
 // Configures using the `ONEBUSAWAY_API_KEY` environment variable
 val client: OnebusawaySdkClientAsync = OnebusawaySdkOkHttpClientAsync.fromEnv()
 
-val params: CurrentTimeRetrieveParams = CurrentTimeRetrieveParams.builder().build()
-val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve(params)
+val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve()
 ```
 
 The asynchronous client supports the same options as the synchronous one, except most methods are [suspending](https://kotlinlang.org/docs/coroutines-guide.html).
@@ -226,9 +223,7 @@ To set a custom timeout, configure the method call using the `timeout` method:
 import org.onebusaway.models.CurrentTimeRetrieveParams
 import org.onebusaway.models.CurrentTimeRetrieveResponse
 
-val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve(
-  params, RequestOptions.builder().timeout(Duration.ofSeconds(30)).build()
-)
+val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve(RequestOptions.builder().timeout(Duration.ofSeconds(30)).build())
 ```
 
 Or configure the default for all method calls at the client level:
@@ -356,9 +351,7 @@ Or configure the method call to validate the response using the `responseValidat
 import org.onebusaway.models.CurrentTimeRetrieveParams
 import org.onebusaway.models.CurrentTimeRetrieveResponse
 
-val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve(
-  params, RequestOptions.builder().responseValidation(true).build()
-)
+val currentTime: CurrentTimeRetrieveResponse = client.currentTime().retrieve(RequestOptions.builder().responseValidation(true).build())
 ```
 
 Or configure the default for all method calls at the client level:
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/AgenciesWithCoverageListParams.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/AgenciesWithCoverageListParams.kt
index 323686c0..52a812e7 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/AgenciesWithCoverageListParams.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/AgenciesWithCoverageListParams.kt
@@ -30,6 +30,8 @@ private constructor(
 
     companion object {
 
+        fun none(): AgenciesWithCoverageListParams = builder().build()
+
         fun builder() = Builder()
     }
 
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/ConfigRetrieveParams.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/ConfigRetrieveParams.kt
index f2cf29f1..344a2ff1 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/ConfigRetrieveParams.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/ConfigRetrieveParams.kt
@@ -27,6 +27,8 @@ private constructor(
 
     companion object {
 
+        fun none(): ConfigRetrieveParams = builder().build()
+
         fun builder() = Builder()
     }
 
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/CurrentTimeRetrieveParams.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/CurrentTimeRetrieveParams.kt
index f360e847..efcc7fc9 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/CurrentTimeRetrieveParams.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/models/CurrentTimeRetrieveParams.kt
@@ -27,6 +27,8 @@ private constructor(
 
     companion object {
 
+        fun none(): CurrentTimeRetrieveParams = builder().build()
+
         fun builder() = Builder()
     }
 
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/AgenciesWithCoverageServiceAsync.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/AgenciesWithCoverageServiceAsync.kt
index be68aa05..dfdc7542 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/AgenciesWithCoverageServiceAsync.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/AgenciesWithCoverageServiceAsync.kt
@@ -13,7 +13,14 @@ interface AgenciesWithCoverageServiceAsync {
      * center of their coverage area.
      */
     suspend fun list(
-        params: AgenciesWithCoverageListParams,
+        params: AgenciesWithCoverageListParams = AgenciesWithCoverageListParams.none(),
         requestOptions: RequestOptions = RequestOptions.none(),
     ): AgenciesWithCoverageListResponse
+
+    /**
+     * Returns a list of all transit agencies currently supported by OneBusAway along with the
+     * center of their coverage area.
+     */
+    suspend fun list(requestOptions: RequestOptions): AgenciesWithCoverageListResponse =
+        list(AgenciesWithCoverageListParams.none(), requestOptions)
 }
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/ConfigServiceAsync.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/ConfigServiceAsync.kt
index c464f3b0..6f22ba50 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/ConfigServiceAsync.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/ConfigServiceAsync.kt
@@ -10,7 +10,11 @@ interface ConfigServiceAsync {
 
     /** config */
     suspend fun retrieve(
-        params: ConfigRetrieveParams,
+        params: ConfigRetrieveParams = ConfigRetrieveParams.none(),
         requestOptions: RequestOptions = RequestOptions.none(),
     ): ConfigRetrieveResponse
+
+    /** config */
+    suspend fun retrieve(requestOptions: RequestOptions): ConfigRetrieveResponse =
+        retrieve(ConfigRetrieveParams.none(), requestOptions)
 }
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/CurrentTimeServiceAsync.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/CurrentTimeServiceAsync.kt
index 73f89f95..968f0e71 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/CurrentTimeServiceAsync.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/async/CurrentTimeServiceAsync.kt
@@ -10,7 +10,11 @@ interface CurrentTimeServiceAsync {
 
     /** current-time */
     suspend fun retrieve(
-        params: CurrentTimeRetrieveParams,
+        params: CurrentTimeRetrieveParams = CurrentTimeRetrieveParams.none(),
         requestOptions: RequestOptions = RequestOptions.none(),
     ): CurrentTimeRetrieveResponse
+
+    /** current-time */
+    suspend fun retrieve(requestOptions: RequestOptions): CurrentTimeRetrieveResponse =
+        retrieve(CurrentTimeRetrieveParams.none(), requestOptions)
 }
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageService.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageService.kt
index e8f4da8a..25a5e566 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageService.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageService.kt
@@ -13,7 +13,14 @@ interface AgenciesWithCoverageService {
      * center of their coverage area.
      */
     fun list(
-        params: AgenciesWithCoverageListParams,
+        params: AgenciesWithCoverageListParams = AgenciesWithCoverageListParams.none(),
         requestOptions: RequestOptions = RequestOptions.none(),
     ): AgenciesWithCoverageListResponse
+
+    /**
+     * Returns a list of all transit agencies currently supported by OneBusAway along with the
+     * center of their coverage area.
+     */
+    fun list(requestOptions: RequestOptions): AgenciesWithCoverageListResponse =
+        list(AgenciesWithCoverageListParams.none(), requestOptions)
 }
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/ConfigService.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/ConfigService.kt
index 317f77fc..f40ab0e1 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/ConfigService.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/ConfigService.kt
@@ -10,7 +10,11 @@ interface ConfigService {
 
     /** config */
     fun retrieve(
-        params: ConfigRetrieveParams,
+        params: ConfigRetrieveParams = ConfigRetrieveParams.none(),
         requestOptions: RequestOptions = RequestOptions.none(),
     ): ConfigRetrieveResponse
+
+    /** config */
+    fun retrieve(requestOptions: RequestOptions): ConfigRetrieveResponse =
+        retrieve(ConfigRetrieveParams.none(), requestOptions)
 }
diff --git a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/CurrentTimeService.kt b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/CurrentTimeService.kt
index 3a489618..844c425f 100644
--- a/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/CurrentTimeService.kt
+++ b/onebusaway-sdk-kotlin-core/src/main/kotlin/org/onebusaway/services/blocking/CurrentTimeService.kt
@@ -10,7 +10,11 @@ interface CurrentTimeService {
 
     /** current-time */
     fun retrieve(
-        params: CurrentTimeRetrieveParams,
+        params: CurrentTimeRetrieveParams = CurrentTimeRetrieveParams.none(),
         requestOptions: RequestOptions = RequestOptions.none(),
     ): CurrentTimeRetrieveResponse
+
+    /** current-time */
+    fun retrieve(requestOptions: RequestOptions): CurrentTimeRetrieveResponse =
+        retrieve(CurrentTimeRetrieveParams.none(), requestOptions)
 }
diff --git a/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageServiceTest.kt b/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageServiceTest.kt
index a4753b7a..43b3732f 100644
--- a/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageServiceTest.kt
+++ b/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/AgenciesWithCoverageServiceTest.kt
@@ -6,7 +6,6 @@ import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
 import org.onebusaway.TestServerExtension
 import org.onebusaway.client.okhttp.OnebusawaySdkOkHttpClient
-import org.onebusaway.models.AgenciesWithCoverageListParams
 
 @ExtendWith(TestServerExtension::class)
 class AgenciesWithCoverageServiceTest {
@@ -19,8 +18,7 @@ class AgenciesWithCoverageServiceTest {
                 .apiKey("My API Key")
                 .build()
         val agenciesWithCoverageService = client.agenciesWithCoverage()
-        val agenciesWithCoverageListResponse =
-            agenciesWithCoverageService.list(AgenciesWithCoverageListParams.builder().build())
+        val agenciesWithCoverageListResponse = agenciesWithCoverageService.list()
         println(agenciesWithCoverageListResponse)
     }
 }
diff --git a/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/ConfigServiceTest.kt b/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/ConfigServiceTest.kt
index 70704a46..2943965f 100644
--- a/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/ConfigServiceTest.kt
+++ b/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/ConfigServiceTest.kt
@@ -6,7 +6,6 @@ import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
 import org.onebusaway.TestServerExtension
 import org.onebusaway.client.okhttp.OnebusawaySdkOkHttpClient
-import org.onebusaway.models.ConfigRetrieveParams
 
 @ExtendWith(TestServerExtension::class)
 class ConfigServiceTest {
@@ -19,7 +18,7 @@ class ConfigServiceTest {
                 .apiKey("My API Key")
                 .build()
         val configService = client.config()
-        val configRetrieveResponse = configService.retrieve(ConfigRetrieveParams.builder().build())
+        val configRetrieveResponse = configService.retrieve()
         println(configRetrieveResponse)
     }
 }
diff --git a/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/CurrentTimeServiceTest.kt b/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/CurrentTimeServiceTest.kt
index 10b9f47d..bd714b98 100644
--- a/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/CurrentTimeServiceTest.kt
+++ b/onebusaway-sdk-kotlin-core/src/test/kotlin/org/onebusaway/services/blocking/CurrentTimeServiceTest.kt
@@ -6,7 +6,6 @@ import org.junit.jupiter.api.Test
 import org.junit.jupiter.api.extension.ExtendWith
 import org.onebusaway.TestServerExtension
 import org.onebusaway.client.okhttp.OnebusawaySdkOkHttpClient
-import org.onebusaway.models.CurrentTimeRetrieveParams
 
 @ExtendWith(TestServerExtension::class)
 class CurrentTimeServiceTest {
@@ -19,8 +18,7 @@ class CurrentTimeServiceTest {
                 .apiKey("My API Key")
                 .build()
         val currentTimeService = client.currentTime()
-        val currentTimeRetrieveResponse =
-            currentTimeService.retrieve(CurrentTimeRetrieveParams.builder().build())
+        val currentTimeRetrieveResponse = currentTimeService.retrieve()
         println(currentTimeRetrieveResponse)
     }
 }