What Is Function Calling? Function calling (also called tool use) allows LLMs to request the execution of functions you define, rather than just returning text. Instead of answering “the weather in London is 18°C” from training knowledge, the model can call a get_weather function with the argument {“location”: “London”}, receive the actual current data, and … Read more
What Is LLM Hallucination? Hallucination refers to LLM outputs that are factually incorrect, fabricated, or unsupported by the model’s input context — presented with the same confident tone as accurate information. The term covers a wide range of failure modes: citing research papers that do not exist, stating incorrect facts with high confidence, generating plausible-sounding … Read more
Why LlamaIndex for Production RAG? LlamaIndex is a data framework built specifically for connecting LLMs to external data sources. While LangChain is a general-purpose LLM application framework, LlamaIndex focuses specifically on the ingestion, indexing, and retrieval pipeline — the components that make RAG applications work well in production. Its abstractions for document loading, chunking strategies, … Read more
What Is Microsoft Phi-4? Phi-4 is Microsoft’s fourth-generation small language model, released in late 2024. It is a 14-billion-parameter dense transformer model designed around a specific thesis: that carefully curated, high-quality training data produces better models than simply scaling up parameter counts on web-scraped data. Microsoft’s Phi series has consistently challenged the assumption that more … Read more
Why LLM Observability Is Different from Traditional Monitoring Traditional software monitoring tracks binary outcomes: did the function return? Did the API respond within SLA? Did the database query succeed? LLM applications add a third dimension that traditional monitoring ignores entirely: quality. A response can be returned quickly, at low cost, with a 200 status code … Read more
Why Enterprise LLM Adoption Is Different Enterprise LLM adoption involves a different set of constraints than individual or startup use. Data governance requirements mean that many of the most valuable enterprise datasets cannot be sent to external APIs without legal review, compliance sign-off, or outright prohibition. Existing IT infrastructure creates integration requirements — LLMs must … Read more
The Open-Source Frontier in 2026 Three model families dominate the open-source LLM landscape in 2026: Meta’s Llama 3 series, Mistral AI’s Mixtral and Mistral models, and Alibaba’s Qwen 2.5 series. All three are genuinely frontier-capable — competitive with GPT-4-level models from two years ago — released under permissive licences, and deployable on consumer hardware at … Read more
Mistral AI: The European Open-Source Challenger Mistral AI is a Paris-based AI lab founded in 2023 by former Meta and Google DeepMind researchers. They have established themselves as the leading European AI company and one of the most important open-source model publishers globally. Their models are known for strong performance relative to parameter count, Apache … Read more
Who Is DeepSeek and Why Do They Matter? DeepSeek is a Chinese AI research lab founded in 2023 as a subsidiary of High-Flyer, a quantitative hedge fund. In a little over a year, they released a series of models that genuinely surprised the AI research community — not because they were incremental improvements, but because … Read more
How to Use This Guide Choosing an LLM in 2026 is genuinely hard because the right model depends on your use case, budget, deployment constraints, and quality requirements. A model excellent for code generation may be mediocre for creative writing. A frontier model that tops benchmarks may cost 20x more than a smaller model that … Read more
