Categories

Jacar categories — explore the topics A rocket whose eyes follow your cursor.
Artificial Intelligence

LLM guardrails: frameworks and their real cost

Guardrails frameworks promise to filter language-model inputs and outputs to block data leaks, harmful content, or hallucinations. After evaluating four of the most popular ones in production, I cover what they actually do, what latency and billing cost they add, and when they pay off over simpler controls.

Artificial Intelligence

AI agent observability: tools and what to instrument first

Agents that chain calls to models, tools and memory are hard to debug without instrumentation designed for them. After a long year running agents in production, I cover what to measure first, which standards are consolidating, and which costly mistakes are avoided by getting the traces right from the start.

Architecture

LLM caches: saving tokens without dropping quality

A caching proxy in front of a language model can cut the token bill significantly, but it introduces subtle risks if the design is not careful. Which cache types work in production, where the usual traps sit, and how to add them without degrading the experience.

Architecture

Inference routers: choosing a model based on the request

An inference router decides which model answers each incoming request, weighing cost, latency and how hard the request actually is. Well-built inference routers cut total token spend by 30 to 70 percent with no quality loss the user can perceive. Four patterns cover most cases: length, task type, an auxiliary classifier, and learned routing.

Artificial Intelligence

Testing with AI: the determinism problem

AI testing breaks the assumption every automated suite was built on, because the same input no longer produces the same output. Anthropic documents that temperature 0.0 is still not fully deterministic, and OpenAI's seed parameter only promises mostly reproducible results. What works instead is a layered belt of checks that catches regressions without tripping over ordinary variance.

Architecture

Agent OS: the concept shaping the new stack layer

The term Agent OS has spent a year gaining traction across research and product circles. It describes a layer that goes well beyond an agent library: request scheduling, context management, persistent memory, and isolation. A look at the real state of that concept.

Architecture

Model Context Protocol in 2025: from announcement to ecosystem

Model Context Protocol turns ten months old since Anthropic's announcement, and it is no longer just a proposal: hundreds of servers, cross-vendor implementations and a public registry now back it. A look at what has worked, what is still weak, and why 2025 marks the shift from curiosity to basic infrastructure.

Artificial Intelligence

GPT-5: public availability and early impressions

After months of rumors, OpenAI released GPT-5 in early August. The first weeks of real-world use show a picture less spectacular than the marketing suggested and more useful than many expected. It is worth separating what is genuinely new from what is merely incremental.

Artificial Intelligence

RAG 2.0: knowledge graphs, vectors, and hybrid

RAG 2.0 means retrieval built from several sources at once rather than a single vector search: dense embeddings, lexical matching, and knowledge graphs that capture relationships between entities, with a reranking layer ordering the final candidates. The 2023 pattern of one vector database plus an LLM no longer describes what production systems actually do.

Artificial Intelligence

Computer Use in production: agents that drive the interface

Computer Use in production works today for narrow, repetitive interface tasks where a human still checks the result. Anthropic shipped it in October 2024 calling it experimental and error-prone, and nine months on that framing still holds: teams run it on real work by constraining scope, not by trusting it end to end.

Artificial Intelligence

Gemini 2.5: context scaling and multimodality

Gemini 2.5 Pro reached preview on 25 March 2025 and general availability at the end of June, alongside the cheaper, faster Gemini 2.5 Flash. Two things separate it from Gemini 2.0: a one-million-token context window that behaves stably to at least 500k, and multimodality that has left the demo stage behind.

Artificial Intelligence

The initial Claude 4 family: first quality tests

Anthropic released Claude Opus 4 and Claude Sonnet 4 on 22 May 2025, the first major naming jump since the 3.5 series. Claude 4 reasons noticeably better over long programming tasks: multi-hour refactors that previously stalled without a human nudge now run further alone, and the family targets agentic, multi-step flows.

Artificial Intelligence

Community MCP servers: which ones are worth it

After more than a thousand community MCP servers appeared, the shortlist worth keeping stays small. The five official Anthropic servers in daily use here are filesystem, git, read-only Postgres, fetch, and memory. Servers wrapping Slack, email, or broad SaaS APIs open more attack surface than they repay, and tool-chaining between servers remains unsolved.

Artificial Intelligence

The knowledge graph era is reborn with LLMs

For a decade, knowledge graphs were an academic idea with few real use cases, held back by the cost of building and maintaining the schema. LLMs have changed that equation: they now extract entities automatically and help anchor answers, audit reasoning, and support agents without hallucinating.

Artificial Intelligence

Continuous evaluation of RAG: dashboards that actually matter

Continuous RAG evaluation catches the quiet kind of failure: the system never goes down, never returns errors, never trips a latency alert, it simply answers worse as the index, the model, and user questions drift. Track retrieval precision, effective recall, faithfulness to the retrieved context, answer relevance, and p99 latency.

Artificial Intelligence

LLM wrappers: when they are a business and when they are not

The LLM wrappers that survived the 2022 to 2024 startup wave own something their underlying model cannot supply: proprietary data, network effects, or a workflow users already live inside. Everything else was a thin prompt layer over an API, and structurally bad margins killed it as inference costs rose with usage.

Artificial Intelligence

LLM agent security: the new class of threats

LLM agent security became a real incident category the moment assistants gained tool access. Agents that call tools expose a far wider attack surface than chatbots, and it now carries assigned CVEs, published audit reports, and its own OWASP Top 10. The spread of the Model Context Protocol and agent-driven corporate workflows built that surface in under 18 months.

Architecture

Applying graph RAG to a real product

Graph RAG layers an explicit graph of entities and relationships on top of retrieval, so a question can be answered by traversing connections rather than by vector similarity alone. Microsoft Research published the GraphRAG paper in April 2024 and open-sourced the code that July. Lighter variants such as LightRAG and HippoRAG followed, running on Neo4j or Memgraph.

Artificial Intelligence

AI governance in enterprise: committees, policies, audits

AI governance in a company means a standing committee, written policies, a model and use-case inventory, risk assessment, and audits. The first provisions of the EU AI Act took effect on 2 February 2025, banning practices such as social scoring and requiring minimum AI literacy for staff. Fines reach 35 million euros or 7 percent of global turnover.

Artificial Intelligence

Claude 3.7 Sonnet: the intermediate step toward the 4 family

Claude 3.7 Sonnet, released by Anthropic on February 24, is a careful refinement rather than a generational jump. The same model answers in standard mode or in an extended thinking mode you switch on per request, trading tokens and latency for better results on hard problems. It also ships Claude Code, a command-line tool for programmers.

Architecture

Microsoft’s GraphRAG in enterprise: patterns that work

GraphRAG has been in real enterprise use for over a year: during indexing, an LLM builds a knowledge graph that answers global questions about a corpus well, precisely where classic RAG fails because no single chunk holds the full answer. Here I compare indexing costs, the cases where it pays off, and the hybrid pattern that teams have settled on.

Artificial Intelligence

o3 in public: the reasoning leap is confirmed

o3-mini, the first public release of OpenAI's o3 reasoning series, clearly improves logic, math, and complex code over GPT-4o, though it answers slower and still hallucinates facts. This analysis, based on weeks of real use, explains where it pays off and where it does not.

Artificial Intelligence

Gemini 2.0: integrated tools and agent mode

Gemini 2.0, announced by Google in December, puts tool use and agent behavior at the center of the product: it is designed to execute actions, not only generate text. Its clearest advantages are Flash's one-million-token context window, cheap input tokens, and first-class access to Search, Maps, Cloud, and Workspace. Claude 3.5 Sonnet still leads on complex reasoning.

Artificial Intelligence

AI-assisted code review: an honest adoption story

Two years running AI-assisted code review in a real team leave a clear balance: AI catches mechanical oversights well and writes useful pull-request summaries, but it struggles with architectural judgment and produces many false positives on subtle bugs. The single decision that helped the most was not blocking merges on its automated comments.

Artificial Intelligence

NPU in the PC: faster, cheaper local AI

Qualcomm, Intel and AMD Copilot+ processors have normalised the presence of an NPU in everyday PCs. A 40 TOPS NPU can run quantised Phi-3 Mini drawing just 5-10 W, versus 40-50 W for a laptop GPU doing the same task. What actually changes for running AI models locally, and when it is worth it.

Artificial Intelligence

How to Evaluate a RAG System Without Fooling Yourself

Measuring RAG quality rigorously takes more than skimming a handful of answers: it requires objective metrics (faithfulness, relevance, context precision, and coverage), a golden set of hundreds of curated questions, and regular human validation of the LLM judge to avoid misleading conclusions.

Architecture

Hybrid Search: Combining BM25 and Vectors Seriously

Hybrid search combines BM25 and vector retrieval to cover what each misses alone. Vectors fail on exact identifiers like SKUs or CVEs; BM25 fails when query and document use different vocabulary for the same idea. Reciprocal Rank Fusion (RRF) merges both rankings without depending on their score scales.

Artificial Intelligence

llama.cpp: Optimisations That Keep Surprising

llama.cpp is the C++ library that powers Ollama and much of the local-LLM ecosystem. 2024 added speculative decoding with two- to three-fold speedups, an RPC server for sharding layers across machines, and a stable GGUF format. Ollama covers 90% of cases; going direct pays off with uncommon hardware or specific flags.

Artificial Intelligence

Ollama in 2024: Running LLMs Locally Without Pain

Ollama became the standard for running large language models locally in 2024. It wraps llama.cpp in a single binary with Docker-style CLI and an OpenAI-compatible API. Phi-3 Mini runs in 4 GB; Llama 3.1 8B Q4 needs 6 GB. For production traffic at scale, vLLM remains the correct choice.

Architecture

Model Context Protocol: Anthropic’s Open Proposal

Model Context Protocol (MCP) is the open standard Anthropic published on 25 November 2024 to connect language models with external data and tools over JSON-RPC 2.0. It does not replace function calling: it standardises the server side, aiming to become for context what the Language Server Protocol is for code editors.

Artificial Intelligence

Product-Market Fit in the AI Era: What Changes

Product-market fit for LLM-powered products still depends on the same classic signals: cohort retention, NPS, and revenue expansion. What changes are the higher quality baseline, faster competitor iteration, and where durable moats come from: proprietary data, workflow integration, and network effects.