diff --git a/build.gradle b/build.gradle
index ef9cc15..064317d 100644
--- a/build.gradle
+++ b/build.gradle
@@ -47,7 +47,7 @@ java {
 
 group = 'com.phenoml.maven'
 
-version = '10.0.0'
+version = '10.1.0'
 
 jar {
     dependsOn(":generatePomFileForMavenPublication")
@@ -78,7 +78,7 @@ publishing {
         maven(MavenPublication) {
             groupId = 'com.phenoml.maven'
             artifactId = 'phenoml-java-sdk'
-            version = '10.0.0'
+            version = '10.1.0'
             from components.java
             pom {
                 name = 'phenoml'
diff --git a/changelog.md b/changelog.md
index a3e18e8..fa92112 100644
--- a/changelog.md
+++ b/changelog.md
@@ -1,3 +1,6 @@
+## 10.1.0 - 2026-03-11
+* New optional `preview` parameter available on workflow execution requests. When enabled, create operations return mock resources instead of persisting to the FHIR server. The response also includes a `preview` field to indicate whether the workflow was executed in preview mode.
+
 ## 10.0.0 - 2026-03-11
 * The `ErrorResponse` class has been removed from the summary types package. If your code references `com.phenoml.api.resources.summary.types.ErrorResponse`, you'll need to update your imports and error handling logic to use alternative error response types available in the SDK.
 
diff --git a/reference.md b/reference.md
index 844429b..944c1a1 100644
--- a/reference.md
+++ b/reference.md
@@ -5857,6 +5857,14 @@ client.workflows().execute(
 
 **inputData:** `Map<String, Object>` — Input data for workflow execution
     
+</dd>
+</dl>
+
+<dl>
+<dd>
+
+**preview:** `Optional<Boolean>` — If true, create operations return mock resources instead of persisting to the FHIR server
+    
 </dd>
 </dl>
 </dd>
diff --git a/src/main/java/com/phenoml/api/core/ClientOptions.java b/src/main/java/com/phenoml/api/core/ClientOptions.java
index 2bb1790..b95aef3 100644
--- a/src/main/java/com/phenoml/api/core/ClientOptions.java
+++ b/src/main/java/com/phenoml/api/core/ClientOptions.java
@@ -32,10 +32,10 @@ private ClientOptions(
         this.headers.putAll(headers);
         this.headers.putAll(new HashMap<String, String>() {
             {
-                put("User-Agent", "com.phenoml.maven:phenoml-java-sdk/10.0.0");
+                put("User-Agent", "com.phenoml.maven:phenoml-java-sdk/10.1.0");
                 put("X-Fern-Language", "JAVA");
                 put("X-Fern-SDK-Name", "com.phenoml.fern:api-sdk");
-                put("X-Fern-SDK-Version", "10.0.0");
+                put("X-Fern-SDK-Version", "10.1.0");
             }
         });
         this.headerSuppliers = headerSuppliers;
diff --git a/src/main/java/com/phenoml/api/resources/workflows/requests/ExecuteWorkflowRequest.java b/src/main/java/com/phenoml/api/resources/workflows/requests/ExecuteWorkflowRequest.java
index a80ec53..0d527b4 100644
--- a/src/main/java/com/phenoml/api/resources/workflows/requests/ExecuteWorkflowRequest.java
+++ b/src/main/java/com/phenoml/api/resources/workflows/requests/ExecuteWorkflowRequest.java
@@ -16,16 +16,21 @@
 import java.util.LinkedHashMap;
 import java.util.Map;
 import java.util.Objects;
+import java.util.Optional;
 
 @JsonInclude(JsonInclude.Include.NON_ABSENT)
 @JsonDeserialize(builder = ExecuteWorkflowRequest.Builder.class)
 public final class ExecuteWorkflowRequest {
     private final Map<String, Object> inputData;
 
+    private final Optional<Boolean> preview;
+
     private final Map<String, Object> additionalProperties;
 
-    private ExecuteWorkflowRequest(Map<String, Object> inputData, Map<String, Object> additionalProperties) {
+    private ExecuteWorkflowRequest(
+            Map<String, Object> inputData, Optional<Boolean> preview, Map<String, Object> additionalProperties) {
         this.inputData = inputData;
+        this.preview = preview;
         this.additionalProperties = additionalProperties;
     }
 
@@ -37,6 +42,14 @@ public Map<String, Object> getInputData() {
         return inputData;
     }
 
+    /**
+     * @return If true, create operations return mock resources instead of persisting to the FHIR server
+     */
+    @JsonProperty("preview")
+    public Optional<Boolean> getPreview() {
+        return preview;
+    }
+
     @java.lang.Override
     public boolean equals(Object other) {
         if (this == other) return true;
@@ -49,12 +62,12 @@ public Map<String, Object> getAdditionalProperties() {
     }
 
     private boolean equalTo(ExecuteWorkflowRequest other) {
-        return inputData.equals(other.inputData);
+        return inputData.equals(other.inputData) && preview.equals(other.preview);
     }
 
     @java.lang.Override
     public int hashCode() {
-        return Objects.hash(this.inputData);
+        return Objects.hash(this.inputData, this.preview);
     }
 
     @java.lang.Override
@@ -70,6 +83,8 @@ public static Builder builder() {
     public static final class Builder {
         private Map<String, Object> inputData = new LinkedHashMap<>();
 
+        private Optional<Boolean> preview = Optional.empty();
+
         @JsonAnySetter
         private Map<String, Object> additionalProperties = new HashMap<>();
 
@@ -77,6 +92,7 @@ private Builder() {}
 
         public Builder from(ExecuteWorkflowRequest other) {
             inputData(other.getInputData());
+            preview(other.getPreview());
             return this;
         }
 
@@ -102,8 +118,22 @@ public Builder inputData(String key, Object value) {
             return this;
         }
 
+        /**
+         * <p>If true, create operations return mock resources instead of persisting to the FHIR server</p>
+         */
+        @JsonSetter(value = "preview", nulls = Nulls.SKIP)
+        public Builder preview(Optional<Boolean> preview) {
+            this.preview = preview;
+            return this;
+        }
+
+        public Builder preview(Boolean preview) {
+            this.preview = Optional.ofNullable(preview);
+            return this;
+        }
+
         public ExecuteWorkflowRequest build() {
-            return new ExecuteWorkflowRequest(inputData, additionalProperties);
+            return new ExecuteWorkflowRequest(inputData, preview, additionalProperties);
         }
     }
 }
diff --git a/src/main/java/com/phenoml/api/resources/workflows/types/ExecuteWorkflowResponse.java b/src/main/java/com/phenoml/api/resources/workflows/types/ExecuteWorkflowResponse.java
index cf3dbfe..435ab7d 100644
--- a/src/main/java/com/phenoml/api/resources/workflows/types/ExecuteWorkflowResponse.java
+++ b/src/main/java/com/phenoml/api/resources/workflows/types/ExecuteWorkflowResponse.java
@@ -26,16 +26,20 @@ public final class ExecuteWorkflowResponse {
 
     private final Optional<Results> results;
 
+    private final Optional<Boolean> preview;
+
     private final Map<String, Object> additionalProperties;
 
     private ExecuteWorkflowResponse(
             Optional<Boolean> success,
             Optional<String> message,
             Optional<Results> results,
+            Optional<Boolean> preview,
             Map<String, Object> additionalProperties) {
         this.success = success;
         this.message = message;
         this.results = results;
+        this.preview = preview;
         this.additionalProperties = additionalProperties;
     }
 
@@ -60,6 +64,14 @@ public Optional<Results> getResults() {
         return results;
     }
 
+    /**
+     * @return Whether the workflow was executed in preview mode
+     */
+    @JsonProperty("preview")
+    public Optional<Boolean> getPreview() {
+        return preview;
+    }
+
     @java.lang.Override
     public boolean equals(Object other) {
         if (this == other) return true;
@@ -72,12 +84,15 @@ public Map<String, Object> getAdditionalProperties() {
     }
 
     private boolean equalTo(ExecuteWorkflowResponse other) {
-        return success.equals(other.success) && message.equals(other.message) && results.equals(other.results);
+        return success.equals(other.success)
+                && message.equals(other.message)
+                && results.equals(other.results)
+                && preview.equals(other.preview);
     }
 
     @java.lang.Override
     public int hashCode() {
-        return Objects.hash(this.success, this.message, this.results);
+        return Objects.hash(this.success, this.message, this.results, this.preview);
     }
 
     @java.lang.Override
@@ -97,6 +112,8 @@ public static final class Builder {
 
         private Optional<Results> results = Optional.empty();
 
+        private Optional<Boolean> preview = Optional.empty();
+
         @JsonAnySetter
         private Map<String, Object> additionalProperties = new HashMap<>();
 
@@ -106,6 +123,7 @@ public Builder from(ExecuteWorkflowResponse other) {
             success(other.getSuccess());
             message(other.getMessage());
             results(other.getResults());
+            preview(other.getPreview());
             return this;
         }
 
@@ -148,8 +166,22 @@ public Builder results(Results results) {
             return this;
         }
 
+        /**
+         * <p>Whether the workflow was executed in preview mode</p>
+         */
+        @JsonSetter(value = "preview", nulls = Nulls.SKIP)
+        public Builder preview(Optional<Boolean> preview) {
+            this.preview = preview;
+            return this;
+        }
+
+        public Builder preview(Boolean preview) {
+            this.preview = Optional.ofNullable(preview);
+            return this;
+        }
+
         public ExecuteWorkflowResponse build() {
-            return new ExecuteWorkflowResponse(success, message, results, additionalProperties);
+            return new ExecuteWorkflowResponse(success, message, results, preview, additionalProperties);
         }
     }