GrepAI Trace Callers

This skill covers using grepai trace callers to find all code locations that call a specific function or method.

When to Use This Skill

• Finding all usages of a function before refactoring

• Understanding function dependencies

• Impact analysis before changes

• Code navigation and exploration

What is Trace Callers?

grepai trace callers answers: "Who calls this function?"

func Login(user, pass) {...} ↑ │ ┌───────┴───────────────────┐ │ Who calls Login()? │ ├───────────────────────────┤ │ • HandleAuth (auth.go:42) │ │ • TestLogin (test.go:15) │ │ • CLI (main.go:88) │ └───────────────────────────┘

Basic Usage

grepai trace callers "FunctionName"

Example

grepai trace callers "Login"

Output:

🔍 Callers of "Login"

Found 3 callers:

1. HandleAuth File: handlers/auth.go:42 Context: user.Login(ctx, credentials)

2. TestLoginSuccess File: handlers/auth_test.go:15 Context: result := Login(testUser, testPass)

3. RunCLI File: cmd/main.go:88 Context: err := auth.Login(username, password)

JSON Output

For programmatic use:

grepai trace callers "Login" --json

Output:

{ "query": "Login", "mode": "callers", "count": 3, "results": [ { "file": "handlers/auth.go", "line": 42, "caller": "HandleAuth", "context": "user.Login(ctx, credentials)" }, { "file": "handlers/auth_test.go", "line": 15, "caller": "TestLoginSuccess", "context": "result := Login(testUser, testPass)" }, { "file": "cmd/main.go", "line": 88, "caller": "RunCLI", "context": "err := auth.Login(username, password)" } ] }

Compact JSON (AI Optimized)

grepai trace callers "Login" --json --compact

Output:

{ "q": "Login", "m": "callers", "c": 3, "r": [ {"f": "handlers/auth.go", "l": 42, "fn": "HandleAuth"}, {"f": "handlers/auth_test.go", "l": 15, "fn": "TestLoginSuccess"}, {"f": "cmd/main.go", "l": 88, "fn": "RunCLI"} ] }

TOON Output (v0.26.0+)

TOON format offers ~50% fewer tokens than JSON:

grepai trace callers "Login" --toon

Output:

callers[3]:

• call_site: context: "user.Login(ctx, credentials)" file: handlers/auth.go line: 42 symbol: name: HandleAuth ...

Note: --json and --toon are mutually exclusive.

Extraction Modes

GrepAI offers two extraction modes:

Fast Mode (Default)

Uses regex patterns. Fast and dependency-free.

grepai trace callers "Login" --mode fast

Precise Mode

Uses tree-sitter AST parsing. More accurate but requires tree-sitter.

grepai trace callers "Login" --mode precise

Comparison

Mode Speed Accuracy Dependencies

fast

⚡⚡⚡ Good None

precise

⚡⚡ Excellent tree-sitter

Configuration

Configure trace in .grepai/config.yaml :

trace: mode: fast # fast or precise

enabled_languages: - .go - .js - .ts - .py - .php - .rs

exclude_patterns: - "_test.go" - ".spec.ts"

Supported Languages

Language Extensions

Go .go

JavaScript .js , .jsx

TypeScript .ts , .tsx

Python .py

PHP .php

C/C++ .c , .h , .cpp , .hpp , .cc , .cxx

Rust .rs

Zig .zig

C# .cs

Java .java

Pascal/Delphi .pas , .dpr

Use Cases

Before Refactoring

Find all usages before renaming

grepai trace callers "getUserById"

Check impact of changing signature

grepai trace callers "processPayment"

Understanding Codebase

Who uses this core function?

grepai trace callers "validateToken"

Find entry points to a module

grepai trace callers "initialize"

Debugging

Where is this function called from?

grepai trace callers "problematicFunction"

Code Review

Verify function usage before approving changes

grepai trace callers "deprecatedMethod"

Handling Common Names

If your function name is common, results may include unrelated code:

Problem

grepai trace callers "get" # Too common, many false positives

Solutions

• Use more specific name:

grepai trace callers "getUserProfile"

• Filter results by path:

grepai trace callers "get" --json | jq '.results[] | select(.file | contains("auth"))'

Combining with Semantic Search

Use together for comprehensive understanding:

Find what Login does (semantic)

grepai search "user login authentication"

Find who uses Login (trace)

grepai trace callers "Login"

Scripting Examples

Bash

Count callers

grepai trace callers "MyFunction" --json | jq '.count'

Get caller function names

grepai trace callers "MyFunction" --json | jq -r '.results[].caller'

Get file paths only

grepai trace callers "MyFunction" --json | jq -r '.results[].file' | sort -u

Python

import subprocess import json

result = subprocess.run( ['grepai', 'trace', 'callers', 'Login', '--json'], capture_output=True, text=True )

data = json.loads(result.stdout) print(f"Found {data['count']} callers of Login:") for r in data['results']: print(f" - {r['caller']} in {r['file']}:{r['line']}")

Common Issues

❌ Problem: No callers found ✅ Solutions:

• Check function name spelling (case-sensitive)

• Ensure file type is in enabled_languages

• Run grepai watch to update symbol index

❌ Problem: Too many false positives ✅ Solutions:

• Use more specific function name

• Add exclude patterns in config

• Filter results with jq

❌ Problem: Missing some callers ✅ Solutions:

• Try --mode precise for better accuracy

• Check if files are in ignore patterns

Best Practices

• Use exact function name: Case matters

• Check symbol index: Run grepai watch first

• Use JSON for scripts: Easier to parse

• Combine with search: Semantic + trace = full picture

• Filter large results: Use jq or grep

Output Format

Trace callers result:

🔍 Callers of "Login"

Mode: fast Language files scanned: 245

Found 3 callers:

1. HandleAuth File: handlers/auth.go:42 Context: user.Login(ctx, credentials)

2. TestLoginSuccess File: handlers/auth_test.go:15 Context: result := Login(testUser, testPass)

3. RunCLI File: cmd/main.go:88 Context: err := auth.Login(username, password)

Tip: Use --json for machine-readable output Use --mode precise for more accurate results