diff --git a/servicetalk-http-api/src/main/java/io/servicetalk/http/api/BlockingStreamingHttpRequest.java b/servicetalk-http-api/src/main/java/io/servicetalk/http/api/BlockingStreamingHttpRequest.java
index cffc89c17f..4434000f93 100644
--- a/servicetalk-http-api/src/main/java/io/servicetalk/http/api/BlockingStreamingHttpRequest.java
+++ b/servicetalk-http-api/src/main/java/io/servicetalk/http/api/BlockingStreamingHttpRequest.java
@@ -294,7 +294,10 @@ default <T> BlockingStreamingHttpRequest transform(TrailersTransformer<T, Buffer
     BlockingStreamingHttpRequest version(HttpProtocolVersion version);
 
     @Override
-    BlockingStreamingHttpRequest fragment(@Nullable String fragment);
+    default BlockingStreamingHttpRequest fragment(@Nullable String fragment) {
+        throw new UnsupportedOperationException("BlockingStreamingHttpRequest#fragment(String) is not supported by " +
+                getClass());
+    }
 
     @Deprecated
     @Override
diff --git a/servicetalk-http-api/src/main/java/io/servicetalk/http/api/HttpRequest.java b/servicetalk-http-api/src/main/java/io/servicetalk/http/api/HttpRequest.java
index 1ad2b8b6f0..bc96c9eea3 100644
--- a/servicetalk-http-api/src/main/java/io/servicetalk/http/api/HttpRequest.java
+++ b/servicetalk-http-api/src/main/java/io/servicetalk/http/api/HttpRequest.java
@@ -137,7 +137,10 @@ default <T> HttpRequest payloadBody(T pojo, HttpSerializer<T> serializer) {
     HttpRequest setQueryParameters(String key, String... values);
 
     @Override
-    HttpRequest fragment(@Nullable String fragment);
+    default HttpRequest fragment(@Nullable String fragment) {
+        throw new UnsupportedOperationException("HttpRequest#fragment(String) is not supported by " +
+                getClass());
+    }
 
     @Override
     HttpRequest version(HttpProtocolVersion version);
diff --git a/servicetalk-http-api/src/main/java/io/servicetalk/http/api/StreamingHttpRequest.java b/servicetalk-http-api/src/main/java/io/servicetalk/http/api/StreamingHttpRequest.java
index 1594ff5987..23ee24c9a2 100644
--- a/servicetalk-http-api/src/main/java/io/servicetalk/http/api/StreamingHttpRequest.java
+++ b/servicetalk-http-api/src/main/java/io/servicetalk/http/api/StreamingHttpRequest.java
@@ -285,7 +285,10 @@ <T, S> StreamingHttpRequest transform(TrailersTransformer<T, S> trailersTransfor
     StreamingHttpRequest method(HttpRequestMethod method);
 
     @Override
-    StreamingHttpRequest fragment(@Nullable String fragment);
+    default StreamingHttpRequest fragment(@Nullable String fragment) {
+        throw new UnsupportedOperationException("StreamingHttpRequest#fragment(String) is not supported by " +
+                getClass());
+    }
 
     @Deprecated
     @Override