#3 High
The Blank Slate
Skipping CLAUDE.md — no project context
! 85% of new users affected, 2-3x more correction rounds
Starting Claude without a CLAUDE.md file means every session wastes 10-15 minutes rebuilding context. Claude generates generic code requiring 2-3x more corrections. 60% of Claude Code support tickets come from this "ghost context" anti-pattern.
DON'T
No CLAUDE.md — Claude guesses everything
# No CLAUDE.md exists "color:#7C5CFC">claude -p "Add a new API endpoint" # Claude guesses: # - Wrong framework (Express instead of Fastify) # - Wrong test runner (Jest instead of Vitest) # - Wrong style (classes instead of functions) # - Wrong directory structure # You spend 20 min correcting...
DO
CLAUDE.md with build commands and conventions
# CLAUDE.md (50-100 lines, specific) ## Build "color:#7C5CFC">npm run dev # Start dev server "color:#7C5CFC">npm test # Run vitest "color:#7C5CFC">npm run lint # ESLint + Prettier ## Conventions - Use Fastify, not Express - Functional components only - Tests: colocate in __tests__/ - API routes: src/routes/{resource}.ts
Sources
HumanLayer Blog Anthropic Best Practices