competition-file-parser-chain

# Competition File Parser Chain Use this skill only as a downstream specialization after `$ctf-sandbox-orchestrator` is already active and has established sandbox assumptions, node ownership, and evidence priorities. If that has not happened yet, return to `$ctf-sandbox-orchestrator` first. Use this skill when the hard part is following a file from ingress through every parser, extractor, converter, or deserializer boundary that matters. Reply in Simplified Chinese unless the user explicitly requests English. ## Quick Start 1. Preserve the original upload and every derived artifact separately. 2. Map the chain in order: ingress, temp storage, archive extraction, format conversion, parser call, deserialization, and final consumer. 3. Record filenames, MIME guesses, extensions, temp paths, and parser choices before mutating anything. 4. Separate client-visible validation from backend parser behavior. 5. Reproduce the smallest file-processing chain that yields the decisive branch or artifact. ## Workflow ### 1. Map File Ingress And Derivation - Record request shape, multipart names, content type, filename, temp paths, upload staging, and storage keys. - Note every derived artifact: extracted archive member, converted preview, generated thumbnail, temp document, or deserialized object. - Keep original file and each derivative labeled separately. ### 2. Trace Parser And Conversion Boundaries - Show which parser, converter, extractor, or deserializer runs at each step. - Record parser-specific decisions driven by extension, MIME, magic bytes, schema, archive member names, or embedded metadata. - Distinguish parsing success, preview success, conversion success, and business-logic acceptance. ### 3. Reduce To The Decisive File Chain - Compress the result to the smallest sequence: upload -> derived artifact -> parser boundary -> resulting effect. - State clearly whether the decisive weakness lives in archive handling, MIME inference, file conversion, path resolution, or deserialization. - If the chain becomes mostly a generic async worker problem after enqueue, hand off to the tighter queue or worker skill. ## Read This Reference - Load `references/file-parser-chain.md` for the ingress checklist, parser checklist, and evidence packaging. ## What To Preserve - Original uploads, derived files, temp paths, storage keys, parser names, and conversion steps - The exact boundary where backend behavior diverges from user-visible validation - One minimal replayable file-processing sequence that reaches the decisive effect