private com.google.protobuf.SingleFieldBuilderV3<
            com.google.cloud.vertexai.api.GroundingChunk.RetrievedContext,
            com.google.cloud.vertexai.api.GroundingChunk.RetrievedContext.Builder,
            com.google.cloud.vertexai.api.GroundingChunk.RetrievedContextOrBuilder>
        getRetrievedContextFieldBuilder() {
      if (retrievedContextBuilder_ == null) {
        if (!(chunkTypeCase_ == 2)) {
          chunkType_ =
              com.google.cloud.vertexai.api.GroundingChunk.RetrievedContext.getDefaultInstance();
        }
        retrievedContextBuilder_ =
            new com.google.protobuf.SingleFieldBuilderV3<
                com.google.cloud.vertexai.api.GroundingChunk.RetrievedContext,
                com.google.cloud.vertexai.api.GroundingChunk.RetrievedContext.Builder,
                com.google.cloud.vertexai.api.GroundingChunk.RetrievedContextOrBuilder>(
                (com.google.cloud.vertexai.api.GroundingChunk.RetrievedContext) chunkType_,
                getParentForChildren(),
                isClean());
        chunkType_ = null;
      }
      chunkTypeCase_ = 2;
      onChanged();
      return retrievedContextBuilder_;
    }
<pre>
Grounding chunk from context retrieved by the retrieval tools.
</pre>

<code>.google.cloud.vertexai.v1.GroundingChunk.RetrievedContext retrieved_context = 2;</code>
java-vertexai/proto-google-cloud-vertexai-v1/src/main/java/com/google/cloud/vertexai/api/GroundingChunk.java