Your First Real Change, Made by an Agent and Checked by You

This chapter installs Claude Code, opens it inside a small shared-list web app, and walks through fixing one real bug — blank items being addable — end to end: describing the project, requesting a narrow change, reading the diff, running tests, manually verifying the behavior, adding a test, and committing. It closes with two recent changes to the tool, Auto permission mode and default model updates, and what to check about each. Episode page & show notes Visit website Getting the tool onto your machine The chapter walks through installing Claude Code as a standalone application rather than through npm, explaining why the native installer (fetched with curl or the PowerShell script) is the recommended path — it updates itself and needs no Node.js runtime — while noting Homebrew, WinGet, and Linux package repositories as valid alternatives, per the setup instructions. It covers system requirements, the sign-in flow through a browser, and the built-in diagnostic reached with slash doctor for fixing installation and network problems, drawn from the CLI reference. Opening a real project Once launched inside a small shared-list web app, the chapter shows the workspace trust prompt, the live session display showing model and context usage, and the two permission modes — Manual, which asks before every write or command, and Auto, now the default for Pro, Max and Team plans, which only interrupts for destructive operations. It draws on the permissions documentation and the interactive mode guide to explain what each mode actually shows you and why reading a diff before approving it matters. Making one change and proving it The core of the chapter is a single fix: stopping blank or whitespace-only list items from being added. It shows the tool describing the project first, proposing a small diff, running the test suite after a command-approval prompt, and then a manual click-through of the app to confirm the behavior actually changed — because a passing suite only proves what it already tested. A new test is added, deliberately watched failing and then passing, before a single readable commit closes the loop. What changed recently in Claude Code A short section flags two changes that affect a first session directly: Auto mode becoming the default permission mode on Pro, Max and Team plans, and Sonnet 5 becoming the default model with support for pinning a default model via environment variable, both listed in the Claude Code changelog and the what's new page.