Contextual Precision
Contextual Precision is a single-turn metric used to evaluate a RAG retriever
Overview
The contextual precision metric is a single-turn RAG metric that uses LLM-as-a-judge to evaluate how well your retriever ranks the retrieved context based on the input query.
Required Parameters
These are the parameters you must supply in your test case to run evaluations for contextual precision metric:
inputstringrequired
The input query you supply to your RAG application.
expected_outputstringrequired
The expected output your RAG application has to generate for a given input.
retrieval_contextlist of stringrequired
The retrieved context your retriever outputs for a given input sorted by their rank.
How Is It Calculated?
The contextual precision metric evaluates each retrieved node using an LLM to check if it is correctly ranked for relevance to the input. It then calculates the final score using the following equation:
\text{Contextual Precision} = \frac{1}{\text{Num of Relevant Nodes}}\sum_{k=1}^{n}(\frac{\text{Num of Relevant Nodes Upto position k}}{k} \times r_k)A high contextual precison score indicates that all the retrieved nodes are in the order of their relevance to the input.
Create Locally
You can create the ContextualPrecisionMetric in deepeval as follows:
from deepeval.metrics import ContextualPrecisionMetric
metric = ContextualPrecisionMetric()Here's a list of parameters you can configure when creating a ContextualPrecisionMetric:
thresholdnumberdefault: 0.5
A float to represent the minimum passing threshold.
modelstring | Objectdefault: gpt-4.1
A string specifying which of OpenAI's GPT models to use OR any custom LLM
model of type
DeepEvalBaseLLM.
include_reasonbooleandefault: true
A boolean to enable the inclusion a reason for its evaluation score.
async_modebooleandefault: true
A boolean to enable concurrent execution within the measure() method.
strict_modebooleandefault: false
A boolean to enforce a binary metric score: 0 for perfection, 1 otherwise.
verbose_modebooleandefault: false
A boolean to print the intermediate steps used to calculate the metric score.
evaluation_templateContextualPrecisionTemplatedefault: deepeval's template
An instance of ContextualPrecisionTemplate object, which allows you to
override the default prompts used to compute the ContextualPrecisionMetric
score.
Create Remotely
For users not using deepeval python, or want to run evals remotely on Confident AI, you can use the contextual precision metric by adding it to a single-turn metric collection. This will allow you to use contextual precision metric for:
- Single-turn E2E testing
- Single-turn component-level testing
- Online and offline evals for traces and spans