dev-cli

name	dev-cli
description	Phase 5 CLI implementation — build command-line interfaces for a child-task with clear argument parsing, exit codes, and scriptable output. Use when: building a command-line interface for a child-task, defining commands/flags/exit codes, making output scriptable, or the Phase 5 CLI slice.

One-Liner

A CLI is an API for scripts: correct exit codes, parseable stdout, errors on stderr, accurate --help, and no interactive prompt in a non-TTY — so automation can depend on it.

Input: the child-task plan.md + design docs.

Implement

• Define commands/subcommands, flags, and arguments; provide --help for each.
• Use correct exit codes (0 success, non-zero per error class) — scripts depend on them.
• Make output scriptable (stable, parseable) and human-readable; keep errors on stderr.
• Follow the language guide in ../../resources/conventions/.

Examples (Bad vs Good)

# BAD: error to stdout, exit 0 on failure, prose mixed into machine output
print("error: not found"); sys.exit(0)            # scripts can't detect the failure
# GOOD: error to stderr, non-zero exit, clean parseable stdout
print("error: not found", file=sys.stderr); sys.exit(2)
print(json.dumps(result))                          # stdout stays scriptable

Self-check

• --help is accurate; exit codes are correct; no interactive prompt in non-TTY mode. Gate: exit codes correct, stdout parseable, errors on stderr, --help accurate.

Handoff

To check-code-review then test-unit (arg parsing/exit codes) and test-integration (end-to-end command runs) as the frozen strategy requires.