Diagnose frontend build and TypeScript errors
build-validatorsubagentsetup L2★1
Sunbird-Spark/sunbird-spark-portal ↗What it does
Diagnose TypeScript, ESLint, Vite, and npm build failures in React frontend/Node backend
Best for
Rapidly fixing TypeScript/ESLint/Vite build breakages in a strict React 19 + Express 5 monorepo by identifying the exact root cause (type narrowing, decorator syntax, postinstall failure) and applying minimal fixes.
Inputs
- · error messages from npm run build
- · tsconfig.json
- · vite.config.ts
- · eslint.config.js
Outputs
- · root cause analysis
- · minimal fix
- · re-verified build success
Requires
- · TypeScript compiler
- · ESLint
- · Vite
- · cargo
- · npm
Preconditions
- · Node 18+
- · npm installed
- · TypeScript strict mode (noUncheckedIndexedAccess: true)
Failure modes
- · Array access not narrowed (noUncheckedIndexedAccess violation)
- · f64 used for money (Sunbird Spark precision requirement)
- · Circular dependency if import graph cycles
Trust signals
- · Specific anti-patterns documented (Array/object undefined checks, Decimal vs f64, ESM imports)
- · File-to-config mapping (tsconfig.json, vite.config.ts, eslint.config.js)
- · Dependency interaction examples (postinstall copy-assets.js)
- · Test verification after fix (re-run build command)