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Atlas Whoff
Atlas Whoff

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Claude Code Mastery: Multi-File Tasks, Tool Loops, and Custom Skills

#productivity #ai #typescript #claudeai

What Claude Code Is Actually For

Claude Code is not a smarter autocomplete. It's an autonomous coding agent that can read your codebase, plan multi-step changes, write code across many files, run commands, and iterate until the task is done.

The developers using it effectively treat it as a junior engineer: give it a clear brief, let it work, review the output.

Starting a Session Right 

# From your project root
claude

# Claude reads CLAUDE.md automatically -- put your project context there
# cat CLAUDE.md
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# CLAUDE.md

## Stack
Next.js 14 App Router, TypeScript strict, Tailwind, Prisma + PostgreSQL, NextAuth v5

## Commands
- dev: npm run dev
- test: npm test
- db: npx prisma studio

## Patterns
- Server Components by default
- Zod validation on all API inputs
- logger.error() for errors, never console.log in production
- All routes require auth unless explicitly public
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Effective Task Framing 

WEAK:
"Add a feature to export user data"

STRONG:
"Add a CSV export endpoint for user data.

 Requirements:
 - GET /api/user/export.csv
 - Auth required (current user only)
 - Export: id, email, name, plan, createdAt
 - Content-Type: text/csv
 - Rate limit: 1 export per hour per user
 - Return 200 with file, 429 if rate limited

 Test it works by checking the Content-Type header."
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Multi-File Tasks

Claude Code shines when a task touches many files:

"Implement soft delete for the Post model.

 1. Add deletedAt DateTime? to the Post schema and migrate
 2. Update all db.post.findMany() calls to filter where deletedAt is null
 3. Add a delete endpoint that sets deletedAt instead of deleting
 4. Add a restore endpoint for admins
 5. Update the dashboard to show active post count only

 Don't change any UI styles or copy."
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Using the Tool Loop

Claude Code can run commands and react to their output:

"Run the test suite. Fix any failing tests. Don't modify test logic --
 only fix the implementation to match what the tests expect."

"Run npx prisma migrate dev. If there are conflicts, resolve them.
 Then run the app and verify the /dashboard route loads without errors."

"Run npm run build. Fix all TypeScript errors that surface.
 Don't change any logic -- only add types or fix type errors."
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When Claude Gets Stuck 

If Claude is going in circles:
1. /clear -- reset context
2. Re-explain the problem with the specific error message
3. Point it at the exact file and line

"The build is failing at app/dashboard/page.tsx:47.
 The error is: Property 'name' does not exist on type 'Session'.
 The session type is defined in types/next-auth.d.ts.
 Fix the type declaration, not the usage."
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The /compact Command

Long sessions accumulate context. Use /compact to summarize and continue:

/compact  # Summarizes conversation, keeps working
/clear    # Full reset -- use when switching tasks
/cost     # See token usage for the session
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Custom Skills That Extend Claude Code

The Ship Fast Skill Pack adds 10 domain-specific commands:

/auth     # Full NextAuth implementation
/pay      # Stripe billing setup
/deploy   # Docker + CI/CD pipeline
/test     # Test generation for any function
/api      # REST endpoint scaffolding
/db       # Prisma schema from plain English
# + 4 more
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Each skill gives Claude deep context before it writes code -- structured, repeatable results instead of vague AI output.

$49 one-time at whoffagents.com

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