retrieval

Claude RAG returns empty answer despite relevant vector retrieval

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Problem: Claude Returns Empty or Irrelevant Answers Despite Relevant Vector Retrieval In a development sandbox we integrate Anthropic Claude via its API with a local FAISS vector store. The retrieval step consistently returns passages that contain the answer, but the final response from Claude is either an empty string or a generic answer that does … Read more

Haystack document retrieval failures after cloud storage API intermittent timeouts during peak traffic

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Problem During peak traffic periods the API gateway that fronts a Haystack‑based search service starts returning 504 Gateway Timeout, 502 Bad Gateway and occasional 429 Too Many Requests errors. The downstream Haystack document store logs show repeated failures when trying to fetch source documents from the cloud storage provider (e.g., AWS S3, GCP Cloud Storage, … Read more

Nginx routing to old embedding model causing RAG retrieval mismatch

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Problem Description In a cloud‑managed deployment the Retrieval‑Augmented Generation (RAG) service began returning unrelated documents. The downstream application logged an “Embedding dimension mismatch” error and occasional 502 Bad Gateway responses such as: 2024/09/20 12:34:56 [error] 27#27: *1023 upstream prematurely closed connection while reading response header from upstream, client: 10.2.3.45, server: rag-api.example.com, request: “POST /embed HTTP/1.1”, … Read more

RAG pipeline returns empty retrieval results on AWS EC2 local dev

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Problem: RAG pipeline returns empty retrieval results on an AWS EC2 instance (local development) During local development on an EC2 t3.medium (Ubuntu 22.04) the LangChain retrieval‑augmented generation (RAG) pipeline executes without errors but always yields the log message “No documents found”. The same code runs correctly on a developer laptop. Typical symptom in the application … Read more

RAG pipeline empty retrieval after Docker container restart in Kubernetes

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Problem – RAG pipeline returns empty retrieval after Docker container restart in Kubernetes Symptom: After a pod restart (e.g., rolling update, node‑drain, or container crash) the Retrieval‑Augmented Generation (RAG) service answers every query with No documents retrieved or an empty list, even though the knowledge base was populated before the restart. Typical log excerpt: 2024-09-15 … Read more

LangChain RetrievalQA returns empty answer after canary deployment on Kubernetes

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Problem Description During a canary rollout of a LangChain RetrievalQA service on a Kubernetes cluster, the API began returning empty strings or irrelevant text despite logs confirming that documents were successfully retrieved from Pinecone. The stable version of the service continues to produce correct, concise answers, while the canary pods intermittently emit responses such as: … Read more

LlamaIndex context window overflow after recursive retrieval

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Problem Statement In a high‑throughput Retrieval‑Augmented Generation (RAG) service built on LlamaIndex, recursive retrieval combined with hybrid search (BM25 + embeddings) caused the assembled prompt to exceed the target LLM’s context window. The overflow manifested as: OpenAI API error: 400 Bad Request – This model’s maximum context length is 8192 tokens LlamaIndexError: Prompt exceeds max token limit … Read more

RAG retrieval pipeline silent failures after embedding model update

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Problem – Silent Retrieval Failures After Embedding Model Update The Retrieval‑Augmented Generation (RAG) pipeline started returning empty result sets while query latency dropped dramatically. No HTTP error was propagated to callers, and the existing Prometheus alerts did not fire. The symptoms appeared during a rolling deployment of a new sentence‑transformer model that changed the embedding … Read more

RAG retrieval pipeline returning empty results after metadata filter update

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Problem – Empty Retrieval Results After Metadata Filter Update In a hybrid‑cloud RAG (Retrieval‑Augmented Generation) deployment, the vector store retrieval pipeline began returning empty result sets and occasional query timeouts after a new metadata filter was added. The failure manifested across on‑premises and cloud‑based retrieval nodes that synchronize Pinecone/Elasticsearch indexes. Typical log excerpt: 2024-07-15T10:42:03.112Z ERROR … Read more

RAG retrieval degradation after MLflow model validation

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Problem – Retrieval‑Augmented Generation (RAG) Hybrid Search Degradation During MLflow Validation During automated pre‑deployment validation runs orchestrated by an MLflow Project in the CI/CD pipeline, the hybrid retriever’s relevance metrics collapse: Recall@10 drops by 40‑50 % compared with manual runs. Logs contain errors such as ScoreNormalizationError: Sparse scores exceed dense scores range and warnings like HybridSearchWeightOverflow. … Read more