LLM Skills vs Tools: The Missing Layer in Agent Design

TLDR: A tool is a single callable capability (search, SQL, calculator). A skill is a reusable mini-workflow that coordinates multiple tool calls with policy, guardrails, retries, and output structure.

16 min read

Little's Law: The Secret Formula for System Performance

TLDR: Little's Law (\(L = \lambda W\)) connects three metrics every system designer measures: \(L\) = concurrent requests in flight, \(\lambda\) = throughput (RPS), \(W\) = average response time. If l

9 min read

Fine-Tuning LLMs: The Complete Engineer's Guide to SFT, LoRA, and RLHF

TLDR: A pretrained LLM is a generalist. Fine-tuning makes it a specialist. Supervised Fine-Tuning (SFT) teaches it your domain's language through labeled examples. LoRA does the same with 99% fewer tr

30 min read

How AI Coding Agents Work: Models, Context, Sessions, and Memory

TLDR: An AI coding agent is an LLM stapled to a tool registry, wrapped in an orchestration loop that painstakingly rebuilds state on every single API call — because the model itself is completely stat

34 min read