AWS Machine Learning Blog

Personalize your generative AI applications with Amazon SageMaker Feature Store

Large language models (LLMs) are revolutionizing fields like search engines, natural language processing (NLP), healthcare, robotics, and code generation. The applications also extend into retail, where they can enhance customer experiences through dynamic chatbots and AI assistants, and into digital marketing, where they can organize customer feedback and recommend products based on descriptions and purchase behaviors.

The personalization of LLM applications can be achieved by incorporating up-to-date user information, which typically involves integrating several components. One such component is a feature store, a tool that stores, shares, and manages features for machine learning (ML) models. Features are the inputs used during training and inference of ML models. For instance, in an application that recommends movies, features could include previous ratings, preference categories, and demographics. Amazon SageMaker Feature Store is a fully managed repository designed specifically for storing, sharing, and managing ML model features. Another essential component is an orchestration tool suitable for prompt engineering and managing different type of subtasks. Generative AI developers can use frameworks like LangChain, which offers modules for integrating with LLMs and orchestration tools for task management and prompt engineering.

Building on the concept of dynamically fetching up-to-date data to produce personalized content, the use of LLMs has garnered significant attention in recent research for recommender systems. The underlying principle of these approaches involves the construction of prompts that encapsulate the recommendation task, user profiles, item attributes, and user-item interactions. These task-specific prompts are then fed into the LLM, which is tasked with predicting the likelihood of interaction between a particular user and item. As stated in the paper Personalized Recommendation via Prompting Large Language Models, recommendation-driven and engagement-guided prompting components play a crucial role in enabling LLMs to focus on relevant context and align with user preferences.

In this post, we elucidate the simple yet powerful idea of combining user profiles and item attributes to generate personalized content recommendations using LLMs. As demonstrated throughout the post, these models hold immense potential in generating high-quality, context-aware input text, which leads to enhanced recommendations. To illustrate this, we guide you through the process of integrating a feature store (representing user profiles) with an LLM to generate these personalized recommendations.

Solution overview

Let’s imagine a scenario where a movie entertainment company promotes movies to different users via an email campaign. The promotion contains 25 well-known movies, and we want to select the top three recommendations for each user based on their interests and previous rating behaviors.

For example, given a user’s interest in different movie genres like action, romance, and sci-fi, we could have an AI system determine the top three recommended movies for that particular user. In addition, the system might generate personalized messages for each user in a tone tailored to their preferences. We include some examples of personalized messages later in this post.

This AI application would include several components working together, as illustrated in the following diagram:

  1. A user profiling engine takes in a user’s previous behaviors and outputs a user profile reflecting their interests.
  2. A feature store maintains user profile data.
  3. A media metadata store keeps the promotion movie list up to date.
  4. A language model takes the current movie list and user profile data, and outputs the top three recommended movies for each user, written in their preferred tone.
  5. An orchestrating agent coordinates the different components.

In summary, intelligent agents could construct prompts using user- and item-related data and deliver customized natural language responses to users. This would represent a typical content-based recommendation system, which recommends items to users based on their profiles. The user’s profile is stored and maintained in the feature store and revolves around their preferences and tastes. It is commonly derived based on their previous behaviors, such as ratings.

The following diagram illustrates how it works.

The application follows these steps to provide responses to a user’s recommendation:

  1. The user profiling engine that takes a user’s historical movie rating as input, outputs user interest, and stores the feature in SageMaker Feature Store. This process can be updated in a scheduling manner.
  2. The agent takes the user ID as input, searches for the user interest, and completes the prompt template following the user’s interests.
  3. The agent takes the promotion item list (movie name, description, genre) from a media metadata store.
  4. The interests prompt template and promotion item list are fed into an LLM for email campaign messages.
  5. The agent sends the personalized email campaign to the end user.

The user profiling engine builds a profile for each user, capturing their preferences and interests. This profile can be represented as a vector with elements mapping to features like movie genres, with values indicating the user’s level of interest. The user profiles in the feature store allow the system to suggest personalized recommendations matching their interests. User profiling is a well-studied domain within recommendation systems. To simplify, you can build a regression algorithm using a user’s previous ratings across different categories to infer their overall preferences. This can be done with algorithms like XGBoost.

Code walkthrough

In this section, we provide examples of the code. The full code walkthrough is available in the GitHub repo.

After obtaining the user interests feature from the user profiling engine, we can store the results in the feature store. SageMaker Feature Store supports batch feature ingestion and online storage for real-time inference. For ingestion, data can be updated in an offline mode, whereas inference needs to happen in milliseconds. SageMaker Feature Store ensures that offline and online datasets remain in sync.

For data ingestion, we use the following code:

from sagemaker.feature_store.feature_group import FeatureGroup

feature_group_name = 'user-profile-feature-group'
feature_group = FeatureGroup(name=feature_group_name, feature_definitions=feature_definitions, sagemaker_session=sess)

#Ingest data
feature_group.ingest(data_frame=data_frame, max_workers=6, wait=True)

For real-time online storage, we could use the following code to extract the user profile based on the user ID:

feature_record = featurestore_runtime_client.get_record(FeatureGroupName=feature_group_name, RecordIdentifierValueAsString=customer_id)
print(feature_record)

Then we rank the top three interested movie categories to feed the downstream recommendation engine:

User ID: 42
Top3 Categories: [‘Animation’, ‘Thriller’, ‘Adventure’]

Our application employs two primary components. The first component retrieves data from a feature store, and the second component acquires a list of movie promotions from the metadata store. The coordination between these components is managed by Chains from LangChain, which represent a sequence of calls to components.

It’s worth mentioning that in complex scenarios, the application may need more than a fixed sequence of calls to LLMs or other tools. Agents, equipped with a suite of tools, use an LLM to determine the sequence of actions to be taken. Whereas Chains encode a hardcoded sequence of actions, agents use the reasoning power of a language model to dictate the order and nature of actions.

The connection between different data sources, including SageMaker Feature Store, is demonstrated in the following code. All the retrieved data is consolidated to construct an extensive prompt, serving as input for the LLM. We dive deep into the specifics of prompt design in the subsequent section. The following is a prompt template definition that interfaces with multiple data sources:­

from langchain.prompts import StringPromptTemplate

class FeatureStorePromptTemplate(StringPromptTemplate):
    
    feature_group_name = 'user-profile-feature-group'
    
    def format(self, **kwargs) -> str:
        user_id = kwargs.pop("user_id")
        feature_record = self.fetch_user_preference_from_feature_store(user_id)
        user_preference = self.rank_user_preference(feature_record)
        
        kwargs["promotion_movie_list"] = self.read_promotion_list()
        kwargs["user_preference"] = user_preference
        return prompt.format(**kwargs)
    
    def fetch_user_preference_from_feature_store(self, user_id):
        
        boto_session = boto3.Session()
        featurestore_runtime_client = boto_session.client('sagemaker-featurestore-runtime')
        feature_record = featurestore_runtime_client.get_record(FeatureGroupName=self.feature_group_name, RecordIdentifierValueAsString=str(user_id))
        return feature_record['Record']
    
    # Rank Top_3_Categories for given user's preference
    def rank_user_preference(self, data) -> str:
        # refer to the details in the notebook
        return str(top_categories_df.values.tolist())
        
    # Get promotion movie list from metadata store
    def read_promotion_list(self,) -> str:
        # refer to the details in the notebook
        return output_string

In addition, we use Amazon SageMaker to host our LLM model and expose it as the LangChain SageMaker endpoint. To deploy the LLM, we use Amazon SageMaker JumpStart (for more details, refer to Llama 2 foundation models from Meta are now available in Amazon SageMaker JumpStart). After the model is deployed, we can create the LLM module:

from langchain import PromptTemplate, SagemakerEndpoint
from langchain.llms.sagemaker_endpoint import LLMContentHandler

class ContentHandler(LLMContentHandler):

    def transform_input(self, prompt: str, model_kwargs: dict) -> bytes:
        # refer to the details in the notebook
        
    def transform_output(self, output: bytes) -> str:
        # refer to the details in the notebook

content_handler = ContentHandler()

sm_llm = SagemakerEndpoint(
    endpoint_name = endpoint_name,
    region_name = aws_region,
    model_kwargs = parameters,
    endpoint_kwargs={"CustomAttributes": 'accept_eula=true'},
    content_handler = content_handler,
)

In the context of our application, the agent runs a sequence of steps, called an LLMChain. It integrates a prompt template, model, and guardrails to format the user input, pass it to the model, get a response, and then validate (and, if necessary, rectify) the model output.

from langchain.chains import LLMChain
llmchain = LLMChain(llm=sm_llm, prompt=prompt_template)
email_content = llmchain.run({'user_id': 4})
print(email_content)

In the next section, we walk through the prompt engineering for the LLM to output expected results.

LLM recommendation prompting and results

Following the high-level concept of engagement-guided prompting as described in the research study Personalized Recommendation via Prompting Large Language Models, the fundamental principle of our prompting strategy is to integrate user preferences in creating prompts. These prompts are designed to guide the LLM towards more effectively identifying attributes within the content description that align with user preferences. To elaborate further, our prompt comprises several components:

  • Contextual relevance – The initial part of our prompt template incorporates media metadata such as item name (movie title), description (movie synopsis), and attribute (movie genre). By incorporating this information, the prompt provides the LLM with a broader context and a more comprehensive understanding of the content. This contextual information aids the LLM in better understanding the item through its description and attributes, thereby enhancing its utility in content recommendation scenarios.
  • User preference alignment – By taking into account a user profile that signifies user preferences, potential recommendations are better positioned to identify content characteristics and features that resonate with target users. This alignment augments the utility of the item descriptions because it enhances the efficiency of recommending items that are relevant and in line with user preferences.
  • Enhanced recommendation quality – The engagement-guided prompt uses user preferences to identify relevant promotional items. We can also use user preference to adjust the tone of the LLM for the final output. This can result in an accurate, informative, and personalized experience, thereby improving the overall performance of the content recommendation system.

The following code shows an example prompt template:

prompt_template = """
Our company, "Classic Cinema" frequently promotes movies that we aim to recommend to our customers. This month, we have several popular movies on promotion.

As an AI agent, you are tasked to assist "Classic Cinema" in crafting an email campaign to recommend relevant movies to users. The recommendations should adhere to several guidelines, including contextual relevance, ensuring the recommendations are strictly from our promotional movie list. Additionally, the recommendations should align with user preferences, suggesting items that are relevant and in harmony with the user's preferred categories. You are to provide precisely three top recommended movies. Finally, please draft the email to reflect the tone of the user's preferred categories. The email should not exceed 100 words.

The recommended movies should be sourced from this contextual relevance movie list:
{promotion_movie_list}.

The user has expressed interest in {user_preference}.

Please ensure the recommendations are relevant, and the tone of the email reflects the tastes of those interested in the {user_preference} movie category.

Ensure the letter appeals to those interested in the {user_preference} movie category, and keep the email campaign within a 100-word limit. """

The following is an example result with user preferences of sci-fi, adventure, and war genres:

Subject: Explore the Frontier of Classic Cinema with Our Sci-Fi, Adventure, and War Movies!

Dear [Name],
Are you ready to embark on a journey through time and space, experience heart-pumping action, and witness the bravery of heroes on the battlefield? Look no further! Classic Cinema proudly presents our carefully curated selection of movies, tailored specifically to your interests in Sci-Fi, Adventure, and War.

First up, we have the iconic “Star Wars: Episode V – The Empire Strikes Back” (1980). This classic installment in the Star Wars saga follows Luke Skywalker’s journey to becoming a Jedi Master, while his friends face off against the evil Empire. With its groundbreaking special effects and memorable characters, this movie is a must-see for any fan of the genre.

Next, we recommend “Interstellar” (2014), a thought-provoking and visually stunning film that delves into the mysteries of time and space. As a group of explorers embark on a quest to save humanity, they encounter breathtaking landscapes and uncover the secrets of the universe.

Lastly, we have “Saving Private Ryan” (1998), a gripping and intense war drama that follows a group of soldiers on a dangerous mission to find and rescue a paratrooper whose brothers have been killed in action. This critically acclaimed film is a powerful tribute to the heroes of World War II.
Don’t miss out on these cinematic masterpieces! Watch them now and experience the thrill of adventure, the wonder of sci-fi, and the bravery of war heroes.
Happy viewing, and may the force be with you!

Best regards,
Classic Cinema Team

The following is another example result with a user preference of documentary, musical, and drama:

Subject: Classic Cinema’s Recommendations for Documentary, Musical, and Drama Lovers

Dear [Name],
We hope this email finds you well and that you’re enjoying the variety of movies available on our platform. At Classic Cinema, we take pride in catering to the diverse tastes of our customers, and we’ve selected three exceptional movies that we believe will resonate with your interest in Documentary, Musical, and Drama.

First up, we have “The Shawshank Redemption” (1994), a powerful and uplifting drama that follows the journey of two prisoners as they find hope and redemption in a corrupt and unforgiving prison system. With its gripping storyline, outstanding performances, and timeless themes, this movie is a must-see for anyone who loves a well-crafted drama.

Next, we recommend “The Lord of the Rings: The Fellowship of the Ring” (2001), an epic adventure that combines breathtaking visuals, memorable characters, and a richly detailed world. This movie is a masterclass in storytelling, with a deep sense of history and culture that will transport you to Middle-earth and leave you wanting more.

Lastly, we suggest “The Pianist” (2002), a profound and moving documentary that tells the true story of Władysław Szpilman, a Polish Jewish pianist who struggled to survive the destruction of the Warsaw ghetto during World War II. This film is a powerful reminder of the human spirit’s capacity for resilience and hope, even in the face of unimaginable tragedy.

We hope these recommendations resonate with your interests and provide you with an enjoyable and enriching movie experience. Don’t miss out on these timeless classics – watch them now and discover the magic of Classic Cinema!
Best regards,
The Classic Cinema Team

We have carried out tests with both Llama 2 7B-Chat (see the following code sample) and Llama 70B for comparison. Both models performed well, yielding consistent conclusions. By using a prompt template filled with up-to-date data, we found it easier to test arbitrary LLMs, helping us choose the right balance between performance and cost. We have also made several shared observations that are worth noting.

Firstly, we can see that the recommendations provided genuinely align with user preferences. The movie recommendations are guided by various components within our application, most notably the user profile stored in the feature store.

Additionally, the tone of the emails corresponds to user preferences. Thanks to the advanced language understanding capabilities of LLM, we can customize the movie descriptions and email content, tailoring them to each individual user.

Furthermore, the final output format can be designed into the prompt. For example, in our case, the salutation “Dear [Name]” needs to be filled by the email service. It’s important to note that although we avoid exposing personally identifiable information (PII) within our generative AI application, there is the possibility to reintroduce this information during postprocessing, assuming the right level of permissions are granted.

Clean up

To avoid unnecessary costs, delete the resources you created as part of this solution, including the feature store and LLM inference endpoint deployed with SageMaker JumpStart.

Conclusion

The power of LLMs in generating personalized recommendations is immense and transformative, particularly when coupled with the right tools. By integrating SageMaker Feature Store and LangChain for prompt engineering, developers can construct and manage highly tailored user profiles. This results in high-quality, context-aware inputs that significantly enhance recommendation performance. In our illustrative scenario, we saw how this can be applied to tailor movie recommendations to individual user preferences, resulting in a highly personalized experience.

As the LLM landscape continues to evolve, we anticipate seeing more innovative applications that use these models to deliver even more engaging, personalized experiences. The possibilities are boundless, and we are excited to see what you will create with these tools. With resources such as SageMaker JumpStart and Amazon Bedrock now available to accelerate the development of generative AI applications, we strongly recommend exploring the construction of recommendation solutions using LLMs on AWS.

About the Authors

Yanwei Cui, PhD, is a Senior Machine Learning Specialist Solutions Architect at AWS. He started machine learning research at IRISA (Research Institute of Computer Science and Random Systems), and has several years of experience building AI-powered industrial applications in computer vision, natural language processing, and online user behavior prediction. At AWS, he shares his domain expertise and helps customers unlock business potentials and drive actionable outcomes with machine learning at scale. Outside of work, he enjoys reading and traveling.

Gordon Wang is a Senior AI/ML Specialist TAM at AWS. He supports strategic customers with AI/ML best practices cross many industries. He is passionate about computer vision, NLP, generative AI, and MLOps. In his spare time, he loves running and hiking.

Michelle Hong, PhD, works as Prototyping Solutions Architect at Amazon Web Services, where she helps customers build innovative applications using a variety of AWS components. She demonstrated her expertise in machine learning, particularly in natural language processing, to develop data-driven solutions that optimize business processes and improve customer experiences.

Bin Wang, PhD, is a Senior Analytic Specialist Solutions Architect at AWS, boasting over 12 years of experience in the ML industry, with a particular focus on advertising. He possesses expertise in natural language processing (NLP), recommender systems, diverse ML algorithms, and ML operations. He is deeply passionate about applying ML/DL and big data techniques to solve real-world problems. Outside of his professional life, he enjoys music, reading, and traveling.