Enhance TokenUsage: Access CachedPromptTextTokens

Introduction

In this article, we will discuss the enhancement of the TokenUsage struct to support accessing the CachedPromptTextTokens data. Currently, the TokenUsage struct in the xai-sdk-go library only provides access to PromptTokens, CompletionTokens, and TotalTokens. However, the underlying SamplingUsage proto object includes a GetCachedPromptTextTokens method, which is not directly accessible through the TokenUsage struct. This article outlines the problem, the proposed solution, alternatives considered, and relevant code samples to provide a comprehensive understanding of the enhancement.

Problem Description

The current implementation of the TokenUsage struct in the xai-sdk-go library lacks the ability to directly access the CachedPromptTextTokens data. While the SamplingUsage proto object does have a GetCachedPromptTextTokens method, it is not exposed through the TokenUsage struct. This limitation requires developers to access the data directly from the proto object, which is less convenient and does not provide a unified interface for accessing token usage information. Specifically, the primary issue is that developers need a more straightforward way to retrieve CachedPromptTextTokens without directly interacting with the proto object. The current methods available in the TokenUsage struct—PromptTokens(), CompletionTokens(), and TotalTokens()—do not include this functionality. This inconsistency in accessing token-related data hinders the ease of use and maintainability of the library. Furthermore, the absence of a dedicated method for CachedPromptTextTokens may lead to code duplication and a less intuitive API for users who need this specific metric. Therefore, enhancing the TokenUsage struct to include a method for retrieving CachedPromptTextTokens is crucial for improving the library's usability and consistency.

Proposed Solution

The solution proposed is to add a new method to the TokenUsage struct that retrieves the CachedPromptTextTokens data. This new method, tentatively named CachedPromptTextTokens(), would simply wrap the proto.GetCachedPromptTextTokens() call. This approach aligns with the existing methods for accessing other token usage data, such as PromptTokens(), CompletionTokens(), and TotalTokens(), thereby providing a consistent and intuitive API. The proposed solution involves adding a new method to the TokenUsage struct, which would directly access the CachedPromptTextTokens from the proto object. This method would mirror the existing methods for retrieving other token-related information, ensuring a consistent API. By implementing this, developers can easily access the cached prompt text tokens without needing to interact directly with the underlying proto object. This enhancement simplifies the process of retrieving token usage data and improves the overall usability of the library. The implementation would involve adding a function similar to the existing token retrieval methods, which would call the GetCachedPromptTextTokens() method on the SamplingUsage proto object. This ensures that the new functionality is seamlessly integrated into the existing structure of the TokenUsage struct.

Alternatives Considered

One alternative considered was to continue retrieving the CachedPromptTextTokens data directly from the proto object. However, this approach was deemed less convenient and inconsistent with the rest of the TokenUsage API. It would also require developers to have a deeper understanding of the underlying proto structure, which is not ideal for usability. Another alternative was to create a separate utility function or helper method to retrieve the data. However, this would introduce additional complexity and not provide a unified access point for token usage information. The primary reason for rejecting these alternatives is the desire for a consistent and intuitive API. Accessing CachedPromptTextTokens directly from the proto object or through a separate utility function would deviate from the existing pattern of using methods on the TokenUsage struct. This inconsistency could lead to confusion and make the API less user-friendly. Additionally, maintaining separate methods or utility functions for different token metrics would increase the complexity of the codebase and potentially lead to code duplication. Therefore, the preferred solution of adding a new method to the TokenUsage struct is the most straightforward and maintainable approach.

Code Samples

Below are relevant code samples demonstrating the current implementation and the proposed enhancement:

Current TokenUsage struct:

// TokenUsage struct
// Currently only wraps PromptTokens, CompletionTokens, TotalTokens
func (u *TokenUsage) PromptTokens() int32 { ... }
func (u *TokenUsage) CompletionTokens() int32 { ... }
func (u *TokenUsage) TotalTokens() int32 { ... }

SamplingUsage proto:

// SamplingUsage proto has CachedPromptTextTokens getter
func (x *SamplingUsage) GetCachedPromptTextTokens() int32 {
    if x != nil {
        return x.CachedPromptTextTokens
    }
    return 0
}

Proposed Enhancement:

// Proposed method to access CachedPromptTextTokens
func (u *TokenUsage) CachedPromptTextTokens() int32 {
    return u.proto.GetCachedPromptTextTokens()
}

The existing code demonstrates the current methods available in the TokenUsage struct, which include PromptTokens(), CompletionTokens(), and TotalTokens(). These methods provide access to the respective token counts. The SamplingUsage proto object, on the other hand, has a GetCachedPromptTextTokens() method, but it is not directly accessible through the TokenUsage struct. The proposed code introduces a new method, CachedPromptTextTokens(), to the TokenUsage struct. This method simply calls the GetCachedPromptTextTokens() method on the proto object, making the cached prompt text tokens accessible in a consistent manner with the other token metrics. This addition ensures that developers can easily retrieve this data without needing to directly interact with the proto object, thereby improving the usability of the library.

Detailed Explanation of the Enhancement

To fully understand the enhancement, it's essential to delve into the specifics of how the new CachedPromptTextTokens() method will function within the TokenUsage struct. Currently, the TokenUsage struct encapsulates information about token usage, providing methods to access PromptTokens, CompletionTokens, and TotalTokens. These methods serve as a convenient interface for developers to retrieve token-related data without needing to interact directly with the underlying proto objects. The proposed enhancement aims to extend this convenience to the CachedPromptTextTokens data, ensuring a consistent and user-friendly API. The CachedPromptTextTokens() method will be added to the TokenUsage struct, and its primary function will be to call the GetCachedPromptTextTokens() method available in the SamplingUsage proto object. This ensures that the cached prompt text tokens are directly accessible through the TokenUsage struct, just like the other token metrics. The method's implementation will be straightforward, consisting of a simple call to the proto object's getter method and returning the result. This approach minimizes complexity and ensures that the enhancement integrates seamlessly with the existing structure of the library. Furthermore, this addition will provide developers with a comprehensive view of token usage, including cached prompt text tokens, all accessible through a unified interface. This simplifies the process of analyzing token consumption and optimizing the performance of applications that use the xai-sdk-go library.

Benefits of the Enhancement

The enhancement of the TokenUsage struct to include the CachedPromptTextTokens() method offers several significant benefits. Firstly, it provides a consistent API for accessing token usage data. Developers can now retrieve all relevant token metrics, including prompt tokens, completion tokens, total tokens, and cached prompt text tokens, through a single interface. This consistency simplifies the development process and reduces the learning curve for new users of the library. Secondly, the enhancement improves usability by eliminating the need to directly interact with the proto object. Developers can now access CachedPromptTextTokens directly from the TokenUsage struct, making the code cleaner and more readable. This also reduces the risk of errors associated with directly accessing the proto object. Thirdly, the addition of the CachedPromptTextTokens() method enhances the functionality of the library. Developers can now easily track and analyze the usage of cached prompt text tokens, which can be valuable for optimizing performance and reducing token consumption. This information can be used to make informed decisions about caching strategies and prompt design. Finally, the enhancement promotes maintainability by centralizing access to token usage data within the TokenUsage struct. This makes it easier to update and maintain the library in the future, as changes to the underlying proto objects will not directly impact the API exposed to developers. Overall, the addition of the CachedPromptTextTokens() method is a valuable enhancement that improves the usability, functionality, and maintainability of the xai-sdk-go library.

Conclusion

In conclusion, enhancing the TokenUsage struct to support accessing CachedPromptTextTokens data is a valuable improvement. It addresses the current limitation of the library and provides a more consistent and intuitive API for developers. The proposed solution of adding a CachedPromptTextTokens() method to the TokenUsage struct aligns with the existing structure and offers several benefits, including improved usability, enhanced functionality, and better maintainability. By implementing this enhancement, the xai-sdk-go library can provide a more comprehensive and user-friendly experience for developers working with token usage data.

For more information on token usage and related topics, you can visit the official OpenAI documentation.