Ragas
Ragas is an open-source evaluation toolkit for Large Language Model applications, with particular depth on Retrieval Augmented Generation (RAG) and agentic systems. Originally created under the Exploding Gradients organization on GitHub and now maintained by Vibrant Labs AI, Ragas is a Python library distributed on PyPI under the Apache 2.0 license. It moves teams from informal "vibe checks" to systematic evaluation loops by providing objective LLM-based and traditional metrics, automated test dataset generation, experiment tracking, and integrations with the broader LLM ecosystem including LangChain, LlamaIndex, OpenAI, Anthropic, and popular observability platforms. Ragas exposes a metrics library covering faithfulness, response relevancy, context precision and recall, factual correctness, semantic similarity, agent tool-use accuracy, SQL equivalence, Nvidia-defined RAG metrics, and general-purpose rubric scoring. The project ships a CLI (`ragas`) with quickstart templates such as `rag_eval`, and is consumed primarily as a `pip install ragas` library rather than as a hosted API service. Ragas is widely cited as a default evaluation harness for RAG applications and has grown a substantial community on GitHub and Discord.
Ragas publishes 1 API on the APIs.io network. Tagged areas include LLM Evaluation, RAG Evaluation, Retrieval Augmented Generation, AI Evaluation, and Open Source.
Ragas’ developer surface includes documentation, getting-started guide, release notes, and 14 more developer resources.
Kin Score
APIs 1
Individual APIs this provider publishes, each with its own machine-readable definition.
Ragas Python Library
The Ragas Python library is the primary surface of the project, installed via `pip install ragas` and imported as `ragas`. It exposes evaluation entry points (`ragas.evaluate`),...
Features 10
Notable capabilities this provider offers.
RAG Evaluation Metrics
Faithfulness, Response Relevancy, Context Precision, Context Recall, Context Entities Recall, and Noise Sensitivity for retrieval augmented generation pipelines.
Agent and Tool-Use Metrics
Topic Adherence, Tool Call Accuracy, Tool Call F1, and Agent Goal Accuracy for evaluating multi-step agentic systems.
Natural Language Comparison
Factual Correctness, Semantic Similarity, BLEU, ROUGE, CHRF, Exact Match, and String Presence metrics for output comparison.
SQL Evaluation
Execution-based Datacompy Score and SQL Query Equivalence metrics for text-to-SQL applications.
General Purpose Scoring
Aspect Critic, Simple Criteria Scoring, Rubrics-based scoring, and instance-specific rubrics for custom evaluation criteria.
Nvidia Metrics
Answer Accuracy, Context Relevance, and Response Groundedness metrics contributed by Nvidia for RAG quality.
Test Data Generation
Automated synthesis of diverse test datasets covering single-hop, multi-hop, and abstract query types over user knowledge bases.
Experiments
Experiment-first workflow comparing prompts, models, and configurations across datasets with iterative result tracking.
Custom Metrics
DiscreteMetric and decorator-based APIs for defining LLM-judge and rule-based custom evaluation metrics.
CLI Quickstart Templates
The `ragas quickstart` command scaffolds evaluation projects including the `rag_eval` template for RAG systems.
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Security Posture 1
Authentication, domain security, vulnerability disclosure, and trust-center signals.
Use Cases 6
What developers build with this provider.
RAG Pipeline Evaluation
Scoring retrieval and generation quality in RAG applications across faithfulness, relevance, and context fidelity.
Agent Evaluation
Measuring tool-call correctness, goal completion, and topic adherence in multi-step LLM agents.
Regression Testing in CI
Running Ragas metrics in CI pipelines to detect quality regressions across prompt, model, and configuration changes.
Model and Prompt Selection
Comparing candidate models and prompt variants on a fixed dataset using Ragas experiments.
Synthetic Test Set Generation
Generating diverse evaluation datasets from a knowledge base for systematic LLM testing.
Text-to-SQL Evaluation
Validating generated SQL against reference queries using execution and structural equivalence metrics.
Integrations 9
Pre-built integrations with other platforms and tools.
LangChain
Native integration for evaluating LangChain chains, retrievers, and agents using Ragas metrics.
LlamaIndex
Integration for evaluating LlamaIndex RAG pipelines and query engines.
OpenAI
Default LLM judge backend uses OpenAI models such as GPT-4 class judges.
Anthropic
Anthropic Claude models supported as LLM judges via the LangChain LLM abstraction.
Hugging Face
Support for Hugging Face embeddings and models as judges, plus dataset interop via the `datasets` library.
LangSmith
Result tracking and trace inspection via LangSmith observability.
Arize Phoenix
Observability integration for tracing Ragas evaluations alongside production LLM traffic.
Helicone
LLM cost and trace observability for Ragas-driven evaluations.
Pandas
Datasets and evaluation results are exposed as pandas DataFrames for analysis.
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Resources
Get Started 1
Portal, sign-up, and the first successful call
Documentation 2
Reference material describing how the API behaves
Build 3
SDKs, sample code, and the tooling you integrate with
Access & Security 1
Authentication, authorization, and security posture
Operate 4
Status, limits, changes, and where to get help
Commercial 1
Pricing, plans, and the legal terms of use
Company 2
The organization behind the API
Other 3
Properties that don't map to a standard resource type