Day 2: First interactive session

Lesson 2 60 min

Lesson note: Day 2 — First interactive session (inside a real repository)

Aligned with the ClaudeForge “Lesson 1.2” naming in setup.sh and the generated README.md.

What this lesson is about

You move from isolated prompts to working inside a real codebase: navigating files, loading only the context you need, making a focused change, and proving it with tests and scripts. The “interactive session” is the claude CLI session in sample-repo, using patterns like /add, /status, and accepting a diff—while tests and verify_session.sh confirm the outcome.

Prerequisites

Git 2.40+
Python 3.11+ (3.12 OK)
Claude Code CLI: npm install -g @anthropic-ai/claude-code → claude --version
For lesson guards: ANTHROPIC_API_KEY unset (per setup.sh / verify_session.sh); use SKIP_* only if you know why.

Learning objectives

Component Architecture

Work in a git-backed sample-repo with a normal src/ layout and pytest.
Learn context discipline: use the context inspector to see which paths to load and rough token cost before a session.
Run a verification loop: install deps → run tests → (optional) interactive claude session → verify_session.sh.
Understand lesson environment rules for early modules: ANTHROPIC_API_KEY unset (CLI / Pro login flow), claude CLI available.

Technical objectives (what the scaffold provides)

Reproducible layout via setup.sh: everything generated under lesson-1-first-session/ next to the script (not dependent on arbitrary cwd).
Editable install + venv (sample-repo/.venv) so installs work on PEP 668–style systems.
Runnable harness: stdlib metrics HTTP server (src/server.py), dashboard (dashboard/index.html), start.sh / stop.sh, demo_metrics.sh to exercise counters.
Makefile shortcuts: make test, make demo, etc.

Success criteria (as documented in the project)

Flowchart

get_user_by_email present in UserAuthService (and tests green).
make test / pytest tests/unit/ passes.
With ./start.sh and ./sample-repo/scripts/demo_metrics.sh, dashboard metrics show non-zero demo-related counters.
For Modules 1–7 style checks: echo $ANTHROPIC_API_KEY empty when using lesson verification (unless you intentionally skip guards).

Out of scope (by design)

Production auth (password hashing is illustrative SHA-256; comments say use bcrypt in production).
Heavy frameworks; metrics server is stdlib-only for the lesson harness.

Learning Objectives

✓ Work in a git-backed sample-repo with a normal src/ layout and pytest.
✓ Learn context discipline: use the context inspector to see which paths to load and rough token cost before a session.
✓ Run a verification loop: install deps → run tests → (optional) interactive claude session → verify_session.sh.
✓ Understand lesson environment rules for early modules: ANTHROPIC_API_KEY unset (CLI / Pro login flow), claude CLI available.

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