#tutorial
All the articles tagged with "tutorial".
- 16 min read
LangChain and LangGraph middleware: seven small lessons
Middleware lets you run your own code around an agent's model and tool calls. Seven tiny Node.js lessons in one file: logging, timing, retries, tool errors, call limits, dynamic models, and run order.
- 17 min read
LangGraph graphs explained: eight small lessons
A graph is just state, nodes and edges. Eight tiny Node.js lessons, with flowcharts for each one: linear, branching, loops, parallel, chat messages, and a full agent graph you build by hand.
- 13 min read
Tool calling from scratch with LangChain and Node.js
A model on its own can only write text. Tools let it do real things. Ten tiny Node.js lessons, with flowcharts: your first tool, the tool-calling loop, many tools, parallel calls, error handling, and building the loop by hand with LangGraph.
- 34 min read
Hybrid search with PostgreSQL, pgvector and TypeScript
Keyword search finds the exact word 'iPhone'. Vector search understands 'Apple smartphone'. One Postgres query that runs both and merges the results.