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.

zero-in