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name: typescript-type-subversion-audit description: Scans TypeScript and TSX code for attempts to bypass the type system, including as any, double-casts through unknown, redundant assertions, suspicious inline ReturnType and Awaited<ReturnType> usage, and single-use local wrapper aliases. Use when auditing src/ for unsafe typing patterns or cleaning up type escapes. compatibility: Requires Node.js and a project-local typescript installation. Defaults to scanning src/**/*.ts and src/**/*.tsx.

TypeScript Type-System Subversion Audit

Use this skill when you need a report-first pass over src/ to find likely attempts to bypass or paper over TypeScript's type system.

The bundled analyzer is conservative by default. It reports high-confidence findings for unsafe casts and review-level findings for inline ReturnType patterns or single-use wrapper aliases.

Default workflow

1. Run the analyzer and save a JSON report.

node .agents/skills/typescript-type-subversion-audit/scripts/find-type-subversions.mjs --source-root src --report /tmp/type-subversions.json

1. Read the text summary first, then inspect the JSON report when you need exact paths, lines, symbols, and suggested fixes.

2. Do not edit files immediately unless the user explicitly asked for remediation. This skill is report-first.

3. For borderline findings, read references/review-guidance.md before proposing code changes.

What it flags

• as any
• double-casts through any or unknown
• redundant assertions where the source type already satisfies the asserted type
• inline ReturnType<...> or Awaited<ReturnType<...>> annotations that look like one-off local plumbing
• non-exported local type aliases that only wrap ReturnType<...> or Awaited<ReturnType<...>> and are used once

Built-in exemptions

• ReturnType<typeof setTimeout> and ReturnType<typeof setInterval>
• JSON.parse(...) as unknown
• parseYaml(...) as unknown
• (await request.json()) as unknown
• (await response.json()) as unknown
• similar .json() decode-boundary hardening to unknown

CLI

node .agents/skills/typescript-type-subversion-audit/scripts/find-type-subversions.mjs --help

Supported flags:

• --project-root <path>
• --source-root <path> default src
• --report <path>
• --format text|json default text

Notes

• The analyzer discovers the repo root by walking upward from the skill directory until it finds both package.json and tsconfig.json.
• The JSON report is intended to be fed back into follow-up cleanup work.
• If a cast looks like a missing platform typing workaround, treat it as a review item and prefer ambient augmentation or a named adapter type over more casting.