Test text prompts (Generative AI)

Test a test prompt to generate ideas using a publisher text model.

Explore further

For detailed documentation that includes this code sample, see the following:

• Send text prompt requests
• Text
• Try text prompts

Code sample

C#

Before trying this sample, follow the C# setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI C# API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

using Google.Cloud.AIPlatform.V1;
using System;
using System.Collections.Generic;
using System.Linq;
using Value = Google.Protobuf.WellKnownTypes.Value;

public class PredictTextPromptSample
{
    public string PredictTextPrompt(
        string projectId = "your-project-id",
        string locationId = "us-central1",
        string publisher = "google",
        string model = "text-bison@001"
    )
    {
        // Initialize client that will be used to send requests.
        // This client only needs to be created
        // once, and can be reused for multiple requests.
        var client = new PredictionServiceClientBuilder
        {
            Endpoint = $"{locationId}-aiplatform.googleapis.com"
        }.Build();

        // Configure the parent resource
        var endpoint = EndpointName.FromProjectLocationPublisherModel(projectId, locationId, publisher, model);

        // Initialize request argument(s)
        var prompt = "Give me ten interview questions for the role of program manager.";

        var instanceValue = Value.ForStruct(new()
        {
            Fields =
            {
                ["prompt"] = Value.ForString(prompt)
            }
        });

        var instances = new List<Value>
        {
            instanceValue
        };

        var parameters = Value.ForStruct(new()
        {
            Fields =
            {
                { "temperature", new Value { NumberValue = 0.2 } },
                { "maxOutputTokens", new Value { NumberValue = 256 } },
                { "topP", new Value { NumberValue = 0.95 } },
                { "topK", new Value { NumberValue = 40 } }
            }
        });

        // Make the request
        var response = client.Predict(endpoint, instances, parameters);

        // Parse and return the content.
        var content = response.Predictions.First().StructValue.Fields["content"].StringValue;
        Console.WriteLine($"Content: {content}");
        return content;
    }
}

Java

Before trying this sample, follow the Java setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Java API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import com.google.cloud.aiplatform.v1.EndpointName;
import com.google.cloud.aiplatform.v1.PredictResponse;
import com.google.cloud.aiplatform.v1.PredictionServiceClient;
import com.google.cloud.aiplatform.v1.PredictionServiceSettings;
import com.google.protobuf.Value;
import com.google.protobuf.util.JsonFormat;
import java.io.IOException;
import java.util.ArrayList;
import java.util.List;

public class PredictTextPromptSample {

  public static void main(String[] args) throws IOException {
    // TODO(developer): Replace these variables before running the sample.
    // Details of designing text prompts for supported large language models:
    // https://cloud.google.com/vertex-ai/docs/generative-ai/text/text-overview
    String instance =
        "{ \"prompt\": " + "\"Give me ten interview questions for the role of program manager.\"}";
    String parameters =
        "{\n"
            + "  \"temperature\": 0.2,\n"
            + "  \"maxOutputTokens\": 256,\n"
            + "  \"topP\": 0.95,\n"
            + "  \"topK\": 40\n"
            + "}";
    String project = "YOUR_PROJECT_ID";
    String location = "us-central1";
    String publisher = "google";
    String model = "text-bison@001";

    predictTextPrompt(instance, parameters, project, location, publisher, model);
  }

  // Get a text prompt from a supported text model
  public static void predictTextPrompt(
      String instance,
      String parameters,
      String project,
      String location,
      String publisher,
      String model)
      throws IOException {
    String endpoint = String.format("%s-aiplatform.googleapis.com:443", location);
    PredictionServiceSettings predictionServiceSettings =
        PredictionServiceSettings.newBuilder().setEndpoint(endpoint).build();

    // Initialize client that will be used to send requests. This client only needs to be created
    // once, and can be reused for multiple requests.
    try (PredictionServiceClient predictionServiceClient =
        PredictionServiceClient.create(predictionServiceSettings)) {
      final EndpointName endpointName =
          EndpointName.ofProjectLocationPublisherModelName(project, location, publisher, model);

      // Initialize client that will be used to send requests. This client only needs to be created
      // once, and can be reused for multiple requests.
      Value.Builder instanceValue = Value.newBuilder();
      JsonFormat.parser().merge(instance, instanceValue);
      List<Value> instances = new ArrayList<>();
      instances.add(instanceValue.build());

      // Use Value.Builder to convert instance to a dynamically typed value that can be
      // processed by the service.
      Value.Builder parameterValueBuilder = Value.newBuilder();
      JsonFormat.parser().merge(parameters, parameterValueBuilder);
      Value parameterValue = parameterValueBuilder.build();

      PredictResponse predictResponse =
          predictionServiceClient.predict(endpointName, instances, parameterValue);
      System.out.println("Predict Response");
      System.out.println(predictResponse);
    }
  }
}

Node.js

Before trying this sample, follow the Node.js setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Node.js API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

/**
 * TODO(developer): Uncomment these variables before running the sample.\
 * (Not necessary if passing values as arguments)
 */
// const project = 'YOUR_PROJECT_ID';
// const location = 'YOUR_PROJECT_LOCATION';
const aiplatform = require('@google-cloud/aiplatform');

// Imports the Google Cloud Prediction service client
const {PredictionServiceClient} = aiplatform.v1;

// Import the helper module for converting arbitrary protobuf.Value objects.
const {helpers} = aiplatform;

// Specifies the location of the api endpoint
const clientOptions = {
  apiEndpoint: 'us-central1-aiplatform.googleapis.com',
};

const publisher = 'google';
const model = 'text-bison@001';

// Instantiates a client
const predictionServiceClient = new PredictionServiceClient(clientOptions);

async function callPredict() {
  // Configure the parent resource
  const endpoint = `projects/${project}/locations/${location}/publishers/${publisher}/models/${model}`;

  const prompt = {
    prompt:
      'Give me ten interview questions for the role of program manager.',
  };
  const instanceValue = helpers.toValue(prompt);
  const instances = [instanceValue];

  const parameter = {
    temperature: 0.2,
    maxOutputTokens: 256,
    topP: 0.95,
    topK: 40,
  };
  const parameters = helpers.toValue(parameter);

  const request = {
    endpoint,
    instances,
    parameters,
  };

  // Predict request
  const response = await predictionServiceClient.predict(request);
  console.log('Get text prompt response');
  console.log(response);
}

callPredict();

Python

Before trying this sample, follow the Python setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Python API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

import vertexai
from vertexai.language_models import TextGenerationModel


def interview(
    temperature: float,
    project_id: str,
    location: str,
) -> str:
    """Ideation example with a Large Language Model"""

    vertexai.init(project=project_id, location=location)
    # TODO developer - override these parameters as needed:
    parameters = {
        "temperature": temperature,  # Temperature controls the degree of randomness in token selection.
        "max_output_tokens": 256,  # Token limit determines the maximum amount of text output.
        "top_p": 0.8,  # Tokens are selected from most probable to least until the sum of their probabilities equals the top_p value.
        "top_k": 40,  # A top_k of 1 means the selected token is the most probable among all tokens.
    }

    model = TextGenerationModel.from_pretrained("text-bison@002")
    response = model.predict(
        "Give me ten interview questions for the role of program manager.",
        **parameters,
    )
    print(f"Response from Model: {response.text}")

    return response.text

Ruby

Before trying this sample, follow the Ruby setup instructions in the Vertex AI quickstart using client libraries. For more information, see the Vertex AI Ruby API reference documentation.

To authenticate to Vertex AI, set up Application Default Credentials. For more information, see Set up authentication for a local development environment.

require "google/cloud/ai_platform/v1"

##
# Vertex AI Predict Text Prompt
#
# @param project_id [String] Your Google Cloud project (e.g. "my-project")
# @param location_id [String] Your Processor Location (e.g. "us-central1")
# @param publisher [String] The Model Publisher (e.g. "google")
# @param model [String] The Model Identifier (e.g. "text-bison@001")
#
def predict_text_prompt project_id:, location_id:, publisher:, model:
  # Create the Vertex AI client.
  client = ::Google::Cloud::AIPlatform::V1::PredictionService::Client.new do |config|
    config.endpoint = "#{location_id}-aiplatform.googleapis.com"
  end

  # Build the resource name from the project.
  endpoint = client.endpoint_path(
    project: project_id,
    location: location_id,
    publisher: publisher,
    model: model
  )

  prompt = "Give me ten interview questions for the role of program manager."

  # Initialize the request arguments
  instance = Google::Protobuf::Value.new(
    struct_value: Google::Protobuf::Struct.new(
      fields: {
        "prompt" => Google::Protobuf::Value.new(
          string_value: prompt
        )
      }
    )
  )

  instances = [instance]

  parameters = Google::Protobuf::Value.new(
    struct_value: Google::Protobuf::Struct.new(
      fields: {
        "temperature" => Google::Protobuf::Value.new(number_value: 0.2),
        "maxOutputTokens" => Google::Protobuf::Value.new(number_value: 256),
        "topP" => Google::Protobuf::Value.new(number_value: 0.95),
        "topK" => Google::Protobuf::Value.new(number_value: 40)
      }
    )
  )

  # Make the prediction request
  response = client.predict endpoint: endpoint, instances: instances, parameters: parameters

  # Handle the prediction response
  puts "Predict Response"
  puts response
end

What's next

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