Agent Instructions

Source: AGENTS.md

You are working in a small TypeScript CLI. Prefer tiny, testable changes.

Table of Contents

• Agent Instructions — Parcel Path
• Setup
• Commands to know
• Coding rules
• Custom skills
• Definition of done

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Agent Instructions — Parcel Path

You are working in a small TypeScript CLI. Prefer tiny, testable changes.

Setup¶

npm install
npm test
npm run typecheck

Commands to know¶

Command	Purpose
npm test	Unit tests (Vitest)
npm run dev -- track --id <id>	Local CLI entry
npm run build	Emit dist/

Coding rules¶

1. One vertical slice at a time — parse input → call carrier adapter → print result.
2. No network in unit tests — mock carrier clients.
3. Never log tracking tokens or full addresses — redact PII in errors and verbose logs.
4. Match existing naming: CarrierAdapter, TrackingEvent, formatTimeline().

Custom skills¶

Day-to-day workflows live in custom-skills/ (add carrier, local track debug, fixtures, PII review, vertical slices). Prefer invoking those skills over re-deriving steps from scratch.

Definition of done¶

• Tests cover the happy path and one failure path
• README.md mentions any new user-facing flag
• Exit codes: 0 success, 1 usage/validation, 2 carrier/runtime failure