CLI Application Code Review Patterns

Stack-specific rules loaded by dh:code-reviewer when CLI entrypoints are detected (argparse, click, typer, commander.js, or similar argument parsing libraries).

Read Review principles before applying these checks; it defines authority, applicability, evidence, and blocking criteria. Establish the command's supported platforms and human/machine output contracts before prescribing an exact flag or exit code.

Exit Codes

• Verify exit status distinguishes success from failure under the documented command contract, including partial-success or best-effort modes where supported.
• Report success status after a required operation failed when callers cannot detect that failure; distinguish an overall failure from a documented recoverable warning.
• Common conventions: 1 for general errors, 2 for usage/argument errors, 3+ for application-specific codes documented in --help
• Verify fatal paths reach a non-zero exit through the framework or explicit exit handling; printing to stderr alone is not a failure signal for a caller that checks exit status.