Grepai Trace Graph

# GrepAI Trace Graph

This skill covers using `grepai trace graph` to build complete call graphs showing all dependencies recursively.

## When to Use This Skill

- Mapping complete function dependencies
- Understanding complex code flows
- Impact analysis for major refactoring
- Visualizing application architecture

## What is Trace Graph?

`grepai trace graph` builds a recursive dependency tree:

```
main
├── initialize
│   ├── loadConfig
│   │   └── parseYAML
│   └── connectDB
│       ├── createPool
│       └── ping
├── startServer
│   ├── registerRoutes
│   │   ├── authMiddleware
│   │   └── loggingMiddleware
│   └── listen
└── gracefulShutdown
    └── closeDB
```

## Basic Usage

```bash
grepai trace graph "FunctionName"
```

### Example

```bash
grepai trace graph "main"
```

Output:
```
🔍 Call Graph for "main"

main
├── initialize
│   ├── loadConfig
│   └── connectDB
├── startServer
│   ├── registerRoutes
│   └── listen
└── gracefulShutdown
    └── closeDB

Nodes: 9
Max depth: 3
```

## Depth Control

Limit recursion depth with `--depth`:

```bash
# Default depth (2 levels)
grepai trace graph "main"

# Deeper analysis (3 levels)
grepai trace graph "main" --depth 3

# Shallow (1 level, same as callees)
grepai trace graph "main" --depth 1

# Very deep (5 levels)
grepai trace graph "main" --depth 5
```

### Depth Examples

**--depth 1** (same as callees):
```
main
├── initialize
├── startServer
└── gracefulShutdown
```

**--depth 2** (default):
```
main
├── initialize
│   ├── loadConfig
│   └── connectDB
├── startServer
│   ├── registerRoutes
│   └── listen
└── gracefulShutdown
    └── closeDB
```

**--depth 3**:
```
main
├── initialize
│   ├── loadConfig
│   │   └── parseYAML
│   └── connectDB
│       ├── createPool
│       └── ping
├── startServer
│   ├── registerRoutes
│   │   ├── authMiddleware
│   │   └── loggingMiddleware
│   └── listen
└── gracefulShutdown
    └── closeDB
```

## JSON Output

```bash
grepai trace graph "main" --depth 2 --json
```

Output:
```json
{
  "query": "main",
  "mode": "graph",
  "depth": 2,
  "root": {
    "name": "main",
    "file": "cmd/main.go",
    "line": 10,
    "children": [
      {
        "name": "initialize",
        "file": "cmd/main.go",
        "line": 15,
        "children": [
          {
            "name": "loadConfig",
            "file": "config/config.go",
            "line": 20,
            "children": []
          },
          {
            "name": "connectDB",
            "file": "db/db.go",
            "line": 30,
            "children": []
          }
        ]
      },
      {
        "name": "startServer",
        "file": "server/server.go",
        "line": 25,
        "children": [
          {
            "name": "registerRoutes",
            "file": "server/routes.go",
            "line": 10,
            "children": []
          }
        ]
      }
    ]
  },
  "stats": {
    "nodes": 6,
    "max_depth": 2
  }
}
```

## Compact JSON

```bash
grepai trace graph "main" --depth 2 --json --compact
```

Output:
```json
{
  "q": "main",
  "d": 2,
  "r": {
    "n": "main",
    "c": [
      {"n": "initialize", "c": [{"n": "loadConfig"}, {"n": "connectDB"}]},
      {"n": "startServer", "c": [{"n": "registerRoutes"}]}
    ]
  },
  "s": {"nodes": 6, "depth": 2}
}
```

## TOON Output (v0.26.0+)

TOON format offers ~50% fewer tokens than JSON:

```bash
grepai trace graph "main" --depth 2 --toon
```

> **Note:** `--json` and `--toon` are mutually exclusive.

## Extraction Modes

```bash
# Fast mode (regex-based)
grepai trace graph "main" --mode fast

# Precise mode (tree-sitter AST)
grepai trace graph "main" --mode precise
```

## Use Cases

### Understanding Application Flow

```bash
# Map entire application startup
grepai trace graph "main" --depth 4
```

### Impact Analysis

```bash
# What depends on this utility function?
grepai tr