What problem does it solve? Developers working on the gcl-core modpacks module need to understand two different modpack archive formats and a multi-step import algorithm before modifying any code, and getting the format rules wrong produces unsafe paths, disallowed downloads, or broken instances. ## Core Features & Use Cases - Format Detection: Identifies Modrinth .mrpack archives via modrinth.index.json and CurseForge packs via a manifest.json with manifestType minecraftModpack, rejecting anything else as UnknownFormat. - Safe Parsing Rules: Documents sha1 requirements, loader dependency constraints, host allowlists, safe_join path checks, and the 8 MiB manifest read cap that prevent malicious archives from escaping the game directory. - Import Algorithm Reference: Describes the full import flow from instance creation through loader install, file placement, hash-based Modrinth lookups, CurseForge batch resolution, override copying, and partial-instance cleanup on failure. - Use Case: Before editing gcl-core modpacks/ to add a new loader or change file placement, read this Skill to learn exactly how PackPlan is built and which errors each malformed input produces. ## Quick Start Read this Skill before modifying the gcl-core modpacks module so the .mrpack and CurseForge parsing rules and import algorithm guide your changes.
