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Learn to use Claude well

Practical, plain-English how-tos, from the fundamentals to shipping real work.

  • From a hand-written character dictionary to real subword tokenizers: how text becomes the numbers a model reads, and why that changes cost.

    LearningBeginnerRead the guide
  • Read a diff, approve or redirect each edit, and keep every change easy to undo, so you can move fast with a coding agent and still trust what lands.

    CodingBeginnerRead the guide
  • Log prompts, tool calls, latencies and outcomes so you can trace a bad AI answer back to its cause and fix the step that failed.

    AgentsAdvancedRead the guide
  • Build a small evaluation set, score outputs against it, and run it on every change so you catch quality regressions before your users do.

    AgentsAdvancedRead the guide
  • Where an AI system actually spends money, tokens, retries, oversized contexts, the wrong model, and the levers that cut spend without hurting quality.

    AgentsAdvancedRead the guide
  • What changes when an agent leaves your laptop: where it runs, how it gets secrets and tools, and the smallest safe first deployment.

    AgentsAdvancedRead the guide
  • Set Claude Cowork up to succeed: point it at the right files, paste the ticket, name the constraints, and say what it should leave alone.

    CodingAdvancedRead the guide
  • Why agents forget between steps, and three simple ways to carry knowledge forward: passing state, scratch space, and stored notes.

    AgentsAdvancedRead the guide
  • What a tool is for an agent, how to describe one clearly, and why the description decides whether the agent picks the right tool.

    AgentsAdvancedRead the guide
  • Guardrails are the checks around a model that validate inputs and outputs, block unsafe actions, and fail safely without making the system useless.

    AgentsAdvancedRead the guide
  • Models time out, refuse, and return junk: design retries, fallbacks, validation, and clear failure messages so one bad call does not take the system down.

    AgentsAdvancedRead the guide
  • Bound an agent with a clear goal, a tool allow-list, step limits, checks, and stop conditions so it finishes instead of looping.

    AgentsAdvancedRead the guide
  • Give an agent real-world abilities by connecting MCP servers, and decide which servers and permissions it gets so it stays safe and useful.

    AgentsAdvancedRead the guide
  • What breaks when AI traffic grows (rate limits, queues and slow calls) and the patterns that keep your system responsive under load.

    AgentsAdvancedRead the guide
  • A debugging loop for AI agents: trace every step, reproduce the bad run, find the one weak step and tighten it until the agent behaves.

    AgentsAdvancedRead the guide
  • Hand a bug to Claude Cowork with a symptom, a way to reproduce, the suspected area, and a clear pass condition, then review the diff it returns.

    CodingAdvancedRead the guide
  • Hand Claude Cowork the work people skip: tests for behaviour you already shipped and fresh docs, with a brief that keeps the output in your house style.

    CodingAdvancedRead the guide
  • When to let Claude reason step by step before it answers, how to ask for it from the Claude Code CLI, and the tasks where thinking first pays off.

    PromptingIntermediateRead the guide
  • Split a large request into a plan and small steps so Claude has clear targets, and use plan mode in Claude Code to review the plan before code changes.

    PromptingIntermediateRead the guide
  • What a vector database does and how to pick one: pgvector for a small project, a dedicated vector store once you need production scale and speed.

    RAGAdvancedRead the guide
  • Split documents into retrievable chunks: sensible sizes, overlap, structure-aware boundaries, and the metadata that makes each chunk findable.

    RAGAdvancedRead the guide
  • Set up the GitHub MCP server so Claude reads issues, pull requests, and code from your repos directly, with no more copy and paste between tabs.

    MCPAdvancedRead the guide
  • What an embedding is in plain English: a list of numbers that captures meaning, so you can search by what text means instead of the exact words it uses.

    RAGAdvancedRead the guide
  • Measure whether your RAG setup answers well: build a labelled question set, score retrieval and generation separately, and track the results.

    RAGAdvancedRead the guide
  • A repeatable loop for diagnosing a bad result and tightening your prompt until Claude gives you what you want, every time you run it.

    PromptingIntermediateRead the guide
  • Telling Claude who to be and how to sound changes which facts it surfaces, how deep it goes, and how the final answer reads to you.

    PromptingIntermediateRead the guide
  • Add a web search MCP server and the official fetch server so Claude Code can look things up online and read live web pages for you.

    MCPAdvancedRead the guide
  • Keep retrieval accurate as your documents change: re-index updates, sync deletions, and clear out stale content on a regular schedule.

    RAGAdvancedRead the guide
  • When to run an MCP server as a local subprocess versus connect to one hosted over HTTP, and the trade-offs each choice carries.

    MCPAdvancedRead the guide
  • Improve retrieval so Claude gets the right passages every time: better chunks, sharper queries, and metadata filters that cut the noise.

    RAGAdvancedRead the guide
  • When pasting documents straight into the prompt is enough, when you need retrieval instead, and how to tell which one your task needs.

    RAGAdvancedRead the guide
  • Add a reranking step to your RAG pipeline so the most relevant passages reach Claude first, instead of getting buried under near-misses.

    RAGAdvancedRead the guide
  • Check MCP server config into the repo so everyone gets the same tools, and keep secrets out of the file with environment variable expansion.

    MCPAdvancedRead the guide
  • A couple of worked examples in the prompt teach Claude the exact format and quality you want, and they work better than describing it in prose.

    PromptingIntermediateRead the guide
  • Four ways to cut Claude hallucinations: ask for sources, let it say it does not know, ground claims in your text, and verify before you trust.

    PromptingIntermediateRead the guide
  • Expose one endpoint of your own API to Claude as a single MCP tool, with a clear input schema and a quick CLI test loop.

    MCPAdvancedRead the guide
  • A clear instruction names four things (the task, the inputs, the output you want and the limits) so Claude does the work you meant.

    PromptingIntermediateRead the guide
  • Stand up a working MCP server with the official SDK, expose a tool and a resource, and connect it to a real client so Claude can use it right away.

    MCPIntermediateRead the guide
  • Build production agents on the harness behind Claude Code: built-in tools, permissions, sessions, and your own custom tools, all from one SDK.

    AgentsAdvancedRead the guide
  • A tour of the Claude Code slash commands and skills worth knowing, what each one does, when to reach for it, and which ones you can safely ignore.

    CodingIntermediateRead the guide
  • Automate formatting, linting, and logging around every tool call, and lock down what an agent is allowed to do with permission modes and deny lists.

    CodingIntermediateRead the guide
  • Install a terminal coding agent, authenticate, point it at a real project, and ship your first committed change in about ten minutes.

    CodingBeginnerRead the guide
  • Plan mode, memory, subagents, hooks, and code review: the everyday habits that make Claude Code fast, predictable, and safe to use on real projects.

    CodingBeginnerRead the guide
  • Let Anthropic run the agent loop and sandbox for you. Define an agent once, then drive it over a simple REST API without managing any infrastructure.

    AgentsAdvancedRead the guide
  • Fill the context window with exactly what the model needs, in the right order, and prune everything else so answers stay accurate and costs stay low.

    CodingIntermediateRead the guide
  • The context window is an agent's only working memory. What you load, what you leave out, and the order you use decide whether it succeeds or spirals.

    AgentsIntermediateRead the guide
  • Hand Claude a folder and a plain-English brief, and Cowork handles the steps, edits, and results while you watch or step away.

    CodingAdvancedRead the guide
  • A clear anatomy of what Claude Code is under the hood, so you can configure it, extend it, and trust it on real work in your own projects.

    CodingAdvancedRead the guide
  • How a coding agent splits work across subagents that each run in their own context, and why a subagent can inherit the main model or use a cheaper one.

    CodingIntermediateRead the guide
  • Write self-contained task briefs that give Claude Cowork everything it needs to finish the job without stopping to ask you questions halfway through.

    CodingAdvancedRead the guide
  • The habits that separate power users from casual users of Claude Code, from a tight CLAUDE.md to plan mode, subagents and reviewing the diff.

    CodingIntermediateRead the guide
  • The building blocks of LangChain (models, prompts, tools and chains) in plain English, plus when a plain provider SDK is all you need.

    AgentsAdvancedRead the guide
  • Model an agent's control flow as a graph of state, nodes and edges, and learn the loops that let an agent act, check its work and pause.

    AgentsAdvancedRead the guide
  • What the Model Context Protocol is, the problem it solves, its three server primitives, and how a request flows from start to finish.

    MCPIntermediateRead the guide
  • Why code retrieval is its own problem, how coding agents find context with grep and structure, and when embeddings help.

    RAGAdvancedRead the guide
  • Retrieval-augmented generation from first principles: chunk, embed, retrieve and ground the answer, then evaluate what you built.

    RAGAdvancedRead the guide
  • Use git worktrees to fan out several Claude Code sessions across independent tasks at the same time, then integrate the results without merge chaos.

    CodingBeginnerRead the guide
  • Install Claude Code, sign in, point it at a real project, and lay the groundwork that makes every later session go smoothly.

    CodingBeginnerRead the guide
  • A practical map of the MCP ecosystem: the three primitives, the kinds of servers, how clients connect, and how to pick servers you can trust.

    MCPBeginnerRead the guide
  • What tool calling is, how the request, decide, run and return loop works, and what makes a good tool, with real examples and no API boilerplate.

    CodingBeginnerRead the guide
  • Claude Cowork is an agentic tab inside Claude Desktop that takes a self-contained brief, runs the work on its own, and hands you back a finished result.

    CodingAdvancedRead the guide
  • Match the task to the mode. Cowork earns its keep on scoped, independent, verifiable work; interactive chat suits exploratory or high-stakes work.

    CodingAdvancedRead the guide
  • Turn repeatable multi-step tasks into pipelines by chaining custom slash commands, plan mode, structured hand-offs, and fan-out subagents inside Claude Code.

    CodingIntermediateRead the guide