Canonical Engineering Manual #06|TinyCTO RAG Bible
Evaluation, Benchmarking & Observability
The RAG Triad of metrics, automated LLM judges, Prediction-Powered Inference (PPI), and OpenTelemetry tracing.
Canon Certified 13 min
#1. The RAG Triad of Core Metrics
Evaluating RAG systems requires decoupling retrieval precision from generation fidelity. The canonical RAG triad comprises:
- Context Precision / Relevance: Did the retrieval pipeline fetch passages directly relevant to the query?
- Groundedness / Faithfulness: Is every claim in the generated response mathematically or logically supported by the retrieved context?
- Answer Relevance: Does the response directly address the user query without irrelevant tangents?
#2. Rigorous Evaluation Methodologies
- Prediction-Powered Inference (PPI): Combining a small set of human ground-truth labels with machine LLM judge predictions to compute statistically sound confidence intervals.
- Synthetic Test Generation: Automatically synthesizing multi-hop questions, unanswerable queries, and adversarial distractors from source corpuses to stress-test pipelines.
- Distributed Telemetry: Instrumenting every pipeline component with OpenTelemetry tracing spans, capturing end-to-end latency, token consumption, and retrieval scores.