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Tagged “rag”

9 posts.

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All Model Architecture19 Training & Alignment22 Inference & Serving18 Agents & Orchestration11 Reasoning & Evaluation26 Safety, Security & Governance7 Platforms & Practice20
Training & Alignment 24 min

250 Documents: Why Data Poisoning Gets Easier as Models Get Bigger

The industry's defence against data poisoning was arithmetic: an attacker needs a percentage of the corpus, and a percentage of 260 billion tokens is unobtainable. In October 2025 the largest poisoning study ever run showed the r…

safety security data-poisoning backdoors ∑ ◫
Platforms & Practice 24 min

A Model Version Is No Longer a File: Registries for Compound AI Systems

Model registries were built to version a trained artefact you own. An LLM application's behaviour comes from a hosted snapshot that retires on someone else's calendar, plus prompts, an index and tools you change weekly. The relea…

model-registry-and-versioning mlops llm-systems evaluation ∑ ◫
Agents & Orchestration 20 min

Agent Memory Systems: Episodic, Semantic, and the Architecture of Remembering

An LLM agent with a million-token window still forgets what you told it last week. Memory is not a bigger context; it is a separate system that decides what to write down, how to summarize it, and what to pull back. Here is how t…

agents memory llm retrieval ∑ ◫
Platforms & Practice 24 min

BM25 Refuses to Die: The Probabilistic Relevance Framework Behind Search's Most Durable Baseline

In 2021 a benchmark of 18 retrieval datasets found that a scoring function from 1994 still beat most neural retrievers outside their training domain. BM25 is not a heuristic that got lucky. It is a deliberate approximation of a p…

classical-ir information-retrieval ranking retrieval ∑ ◫
Model Architecture 23 min

Context Rot: Why Bigger Context Windows Don't Mean Better Retrieval

A million-token window promises perfect recall of everything you feed it. Controlled tests on 18 frontier models show recall degrading steadily, unevenly, and well before the window fills, a pattern researchers now call context rot.

llm long-context rag context-engineering ∑ ◫
Platforms & Practice 24 min

Query Understanding Is the Hidden Half of Search: From Broder's Taxonomy to LLM Query Rewriting

An LLM-written pseudo-document lifts BM25 by 15 nDCG@10 points on TREC DL 2019, and turns a 16 ms search into one that waits over two seconds for the model. Query understanding decides what the engine searches for before ranking …

query-understanding information-retrieval retrieval rag ∑ ◫
Platforms & Practice 10 min

Retrieval Is a Ranking Problem: Why Your RAG System Doesn't Need a Better Embedding Model

Teams tune the embedding model and the vector database, then wonder why answers are still wrong. Both are the least important parts of the stack. Retrieval is a two-stage ranking problem, and information retrieval solved the shap…

rag retrieval reranking chunking ∑ ◫
Platforms & Practice 3 min

Stop fine-tuning for facts: the silent productivity tax of mis-matched tools

Most teams reach for fine-tuning when they should reach for retrieval. The cost is not just dollars - it is months of confused engineers trying to figure out why the model started lying again.

rag retrieval fine-tuning architecture
Platforms & Practice 24 min

What Structure Buys You: Knowledge Graphs in the Age of Language Models

In 2019 a masked language model recalled facts almost as well as a relation extractor with an oracle entity linker, and people asked whether knowledge graphs were finished. They were not, but the reason is narrower than their adv…

knowledge-graphs rag retrieval hybrid-retrieval ∑ ◫
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