Lab ch04: From Atlas to Eval Set

Following the Chapter 4 Lab steps:

Your input is your Chapter 3 failure mode atlas v1. python labs/ch04/run.py: the generation pipeline drafts YAML by "failure mode × persona" into labs/ch04/drafts/ (default seven modes × four personas; pass your own mode names via --modes, control drafts per cell with --n).
Review every draft by hand: edit until it reads like a real user, or throw it away. Watch synthetic distortion in particular. When several angry cases read as the same anger, rewrite them yourself, and write different angers.
For every sev-1 failure mode, hand-write at least one anchor case, made assertion-decidable wherever possible (golden-task-design-protocol.md in templates/ch04/).
Land the reviewed cases as cases/cases-50, then run python labs/ch04/coverage.py: which cells are empty? Are the sev-1 rows non-zero? Rule every empty cell "fill" or "reasoned empty" and log it in the annotation bar of templates/ch04/coverage-matrix.md.
Drill one expiry: suppose the refund ceiling rises ($500 → $680, drill only, the policy ledger stays unchanged), check the basis register in templates/ch04/label-expiry-policy.md, and list the affected cases.

Without a model API: run.py needs a model (it exits with an error; MODEL_FAKE=1 is test-only), but all drafts can be hand-written, the pipeline only saves first-draft effort; coverage.py is fully offline and runs any time.

Files in this lab

Full directory: repo/labs/ch04/