Claude Opus 5.5 tool_choice 400: 3 SDKs Tested (2026)
September 25, 2026
Claude Opus 5.5 rejects forced tool_choice with a 400. I captured what the AI SDK, LangChain and the raw SDK actually send, and built a preflight check.
#langchain
Token-Aware Text Chunking for RAG in TypeScript (2026)
June 28, 2026
Token-aware text chunking for RAG in TypeScript: recursive splitting with @langchain/textsplitters and js-tiktoken, plus chunk size and overlap tuning.
Local AI with Ollama + Qwen3: RAG, Agents & Vector Stores
March 5, 2026
Production local AI on your own hardware: Ollama + Qwen3, ChromaDB RAG, tool-calling agents, quantization, and security. Runnable code, zero cloud.
Building a Robust RAG System: A Complete Implementation Guide
February 21, 2026
Build a robust RAG system end to end: chunking, embeddings, vector stores, hybrid retrieval, reranking, and eval harnesses you actually need in production.
Mastering LangChain Agents: A Complete Hands-On Tutorial
February 18, 2026
Build, test, and ship LangChain agents — how tool use, memory, and reasoning loops work, with performance, security, and monitoring patterns for production.