Zero In

Zero In

When To Activate

Instructions

Before ANY Search

Answer these four questions:

State it in one sentence. Be specific.

BAD:  "authentication stuff"
GOOD: "the function that validates JWT tokens on API requests"

If you can't state it in one sentence, you don't know what you're looking for.

Describe what you expect to find:

• File type? (.ts, .py, .go, config file?)
• Function, class, or config?
• Roughly how big? (one-liner vs module?)
• What would it import/use?

Example: "Probably a middleware function in TypeScript, imports jsonwebtoken
or jose, has 'verify' or 'validate' in the name, 20-50 lines"

Based on project conventions:

• Which directory? (src/, lib/, middleware/, utils/?)
• What would the file be named?
• Near what other code?

Example: "Likely in src/middleware/ or src/auth/, file probably named
auth.ts, jwt.ts, or middleware.ts"

Check the project structure first if unsure:

ls -la src/
find . -type d -name "*auth*" -o -name "*jwt*"

List synonyms, abbreviations, variations:

Example for JWT validation:
- verify, validate, check, authenticate
- jwt, token, bearer, authorization
- middleware, handler, guard, interceptor

Your first search term is rarely the one the codebase uses.

Then Search

Now search, using insights from scoping:

# Start with WHERE + ALIASES
grep -r "verify.*token" src/middleware/
grep -r "jwt" src/auth/

# If needed, broaden
grep -r "token" src/ --include="*.ts"

Verify The Result

Before declaring "found it":

• Does this match what I described in step 2?
• Is this THE thing, or just A thing that mentions it?
• If it's a function, trace who calls it
• If it's config, trace what uses it

Output Format

## Search Scope

**Looking for:** [one sentence]

**Would look like:** [description]

**Likely location:** [directories/files]

**Search terms:** [list of aliases]

## Search Results

Found: [file:line]

Verified: [Yes/No - why]

NEVER

• Start grepping without answering the four questions
• Search for vague terms ("stuff", "thing", "code")
• Stop at the first result without verifying it's THE answer
• Broaden search before narrowing location
• Ignore project structure/conventions

ALWAYS

• State what you're looking for in one sentence first
• Check project structure before searching
• List 3+ aliases/synonyms for your search term
• Verify the result matches your expected shape
• Narrow by location before broadening by term

Example

User: "Find where we handle rate limiting"

Scoping:

Looking for: The middleware or function that tracks request counts and returns 429 when limit exceeded

Would look like: Middleware function, probably uses Redis or in-memory store, has "rate" or "limit" or "throttle" in name, checks request count, returns 429

Likely location: src/middleware/, maybe src/api/, file named rateLimit.ts or throttle.ts

Search terms: rate, limit, throttle, 429, tooMany, requests

Search:

# Check structure first
ls src/middleware/
# Found: auth.ts, cors.ts, rateLimit.ts  <-- bingo

# Verify
grep -n "429\|rate\|limit" src/middleware/rateLimit.ts

Result: src/middleware/rateLimit.ts:23 - rateLimiter middleware using Redis, returns 429 after 100 req/min.

Verified: Yes - matches expected shape (middleware, uses Redis, returns 429).

The Failure That Spawned This Skill

Grepping "auth" in a 50k line codebase. 200+ results. Refined to "login". Still 80 results. Spent 20 minutes reading wrong files. Finally found it in src/middleware/session.ts - wasn't called "auth" or "login" anywhere. Should have asked "where would session validation live?" first.