Turn Contextual Recall
The turn contextual recall metric is a conversational metric that evaluates whether the retrieval context contains sufficient information to support the expected outcome throughout a conversation.
Required Arguments
To use the TurnContextualRecallMetric, you'll have to provide the following arguments when creating a ConversationalTestCase:
turns-
expected_outcome
You must provide the role, content, and retrieval_context for evaluation to happen. Read the How Is It Calculated section below to learn more.
Usage
First, set the eval mode:
deepeval set-eval-mode llm # LLM-as-a-judge (default)
deepeval set-eval-mode hybrid # LLM extracts, Jev decides
deepeval set-eval-mode system_one # Jev-as-a-judge, no LLMThe TurnContextualRecallMetric() can be used for end-to-end multi-turn evaluation:
from deepeval.test_case import Turn, ConversationalTestCase
from deepeval.metrics import TurnContextualRecallMetric
from deepeval import evaluate
content = "We offer a 30-day full refund at no extra cost."
retrieval_context = [
"All customers are eligible for a 30 day full refund at no extra cost."
]
convo_test_case = ConversationalTestCase(
turns=[
Turn(role="user", content="What if these shoes don't fit?"),
Turn(role="assistant", content=content, retrieval_context=retrieval_context)
],
expected_outcome="The chatbot must explain the store policies like refunds, discounts, ..etc.",
)
metric = TurnContextualRecallMetric(threshold=0.5)
# To run metric as a standalone
# metric.measure(convo_test_case)
# print(metric.score, metric.reason)
evaluate(test_cases=[convo_test_case], metrics=[metric])There are TEN optional parameters when creating a TurnContextualRecallMetric:
- [Optional]
threshold: a number representing the minimum passing threshold. Can also be set toNoneto run the metric in score-only mode. Defaulted to0.5. - [Optional]
model: a string specifying which of OpenAI's GPT models to use, OR any custom LLM model of typeDeepEvalBaseLLM. Defaulted togpt-5.4. - [Optional]
include_reason: a boolean which when set toTrue, will include a reason for its evaluation score. Defaulted toTrue. - [Optional]
strict_mode: a boolean which when set toTrue, enforces a binary metric score: 1 for perfection, 0 otherwise. It also overrides the current threshold and sets it to 1. Defaulted toFalse. -
[Optional]
async_mode: a boolean which when set toTrue, enables concurrent execution within themeasure()method. Defaulted toTrue. - [Optional]
verbose_mode: a boolean which when set toTrue, prints the intermediate steps used to calculate said metric to the console, as outlined in the How Is It Calculated section. Defaulted toFalse. - [Optional]
window_size: an integer which defines the size of the sliding window of turns used during evaluation. Defaulted to10. - [Optional]
flaky: a boolean which when set toTrue, marks the metric as flaky. Defaulted toFalse. - [Optional]
system_one_model: the Jev model to use, as a string or aDeepEvalBaseSystemOneModel. Only used underhybridorsystem_oneeval_mode. Defaulted tojev-latest. - [Optional]
eval_mode:llm,hybridorsystem_one, choosing whether an LLM, Jev, or both judge. Defaulted to the configured eval mode (llmunless set).
As a standalone
You can also run the TurnContextualRecallMetric on a single test case as a standalone, one-off execution.
...
metric.measure(convo_test_case)
print(metric.score, metric.reason)How Is It Calculated?
You can change how the TurnContextualRecallMetric is calculated by setting the eval mode.
LLM-as-a-judge
The TurnContextualRecallMetric score is calculated according to the following equation:
The TurnContextualRecallMetric first constructs a sliding windows of turns. For each window, it:
- Breaks down the expected outcome into individual sentences or statements
- Evaluates each sentence to determine if it can be attributed to any node in the retrieval context
- Calculates the interaction score as the ratio of attributable sentences to total sentences
The final score is the average of all recall scores across the conversation. This measures whether your retrieval system is providing sufficient information to generate the expected responses.
Hybrid
Under the hybrid eval mode, the expected_outcome is split into sentences in code for each window, and Jev, a System One model, answers one yes/no question per sentence: can it be attributed to that window's retrieval_context? P(yes) >= 0.5 counts as attributable. The equation and the LLM-written reasons are unchanged. If a Jev call fails, the LLM makes that decision instead.
Jev-as-a-judge
Under the system_one eval mode, Jev judges the whole metric in one request. It is sent the whole conversation (with each assistant turn's retrieval_context) and the expected_outcome and asked three questions:
| Question | Type | Weight |
|---|---|---|
Every sentence in expected_outcome can be attributed to the facts in the retrieval_context of the assistant turns in turns. | Noul | 2 |
The retrieval_context of the assistant turns in turns contains the key facts needed to reach expected_outcome. | Noul | 1 |
How much of expected_outcome can be attributed to the facts in the retrieval_context of the assistant turns in turns? (None of it → All of it) | Score | 1 |
Each answer becomes a value in and the score is their weighted mean. No LLM is called: the reason lists each answer with its probability, and metric.confidence reports how decisive Jev was.
FAQs
When should I use TurnContextualRecallMetric instead of the single-turn version?
ConversationalTestCase and you want to confirm each turn retrieved everything needed for the expected_outcome. The single-turn ContextualRecallMetric checks one query/context pair only.Why does recall require expected outcome when relevancy doesn't?
expected_outcome into statements and checks how many map to a node in the retrieval_context. Without it there's nothing to test completeness against, which is why relevancy (referenceless) doesn't need it.How is recall different from relevancy and precision?
My bot missed a detail the user needed — does a low recall confirm it's a retriever problem?
retrieval_context never contained the info the expected_outcome needed, so the generator never had it. Fix the retriever (chunking, embeddings, top-k) before blaming the LLM.