CustomMetricDefinition
The definition of a custom metric for use in an Amazon Bedrock evaluation job. A custom metric definition includes a metric name, prompt (instructions) and optionally, a rating scale. Your prompt must include a task description and input variables. The required input variables are different for model-as-a-judge and RAG evaluations.
For more information about how to define a custom metric in Amazon Bedrock, see Create a prompt for a custom metrics (LLM-as-a-judge model evaluations) and Create a prompt for a custom metrics (RAG evaluations).
Contents
- instructions
-
The prompt for a custom metric that instructs the evaluator model how to rate the model or RAG source under evaluation.
Type: String
Length Constraints: Minimum length of 1. Maximum length of 5000.
Required: Yes
- name
-
The name for a custom metric. Names must be unique in your AWS region.
Type: String
Length Constraints: Minimum length of 1. Maximum length of 63.
Pattern:
[0-9a-zA-Z-_.]+Required: Yes
- ratingScale
-
Defines the rating scale to be used for a custom metric. We recommend that you always define a ratings scale when creating a custom metric. If you don't define a scale, Amazon Bedrock won't be able to visually display the results of the evaluation in the console or calculate average values of numerical scores. For more information on specifying a rating scale, see Specifying an output schema (rating scale).
Type: Array of RatingScaleItem objects
Array Members: Minimum number of 1 item. Maximum number of 10 items.
Required: No
See Also
For more information about using this API in one of the language-specific AWS SDKs, see the following: