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
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
grepai trace callers "getUserById"
grepai trace callers "processPayment"
Understanding Codebase
grepai trace callers "validateToken"
grepai trace callers "initialize"
Debugging
grepai trace callers "problematicFunction"
Code Review
grepai trace callers "deprecatedMethod"
Handling Common Names
If your function name is common, results may include unrelated code:
Problem
grepai trace callers "get"
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:
grepai search "user login authentication"
grepai trace callers "Login"
Scripting Examples
Bash
grepai trace callers "MyFunction" --json | jq '.count'
grepai trace callers "MyFunction" --json | jq -r '.results[].caller'
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
