codemap

name	codemap
description	Navigate codebases efficiently using structural indexes. Use when finding symbol definitions (classes, functions, methods), exploring file structure, or locating code by name. Reduces token consumption by 60-80% through targeted line-range reads instead of full file scans.
allowed-tools	Read, Bash, Glob, Grep
user-invocable	true

CodeMap - Codebase Structural Index

Navigate codebases efficiently using pre-built structural indexes stored in .codemap/ directories.

When to Use This Skill

USE CodeMap when:

• Finding where a class, function, method, or type is defined
• Understanding a file's structure before reading it
• Searching for symbols by name
• Reducing token usage during codebase exploration

READ full files when:

• Understanding implementation details
• Making edits to code
• The symbol isn't in the index (new/untracked file)

Quick Reference

# Find a symbol by name (case-insensitive)
codemap find "SymbolName"

# Filter by type
codemap find "handle" --type method
codemap find "User" --type class
codemap find "Config" --type interface

# Show file structure with all symbols
codemap show path/to/file.ts

# Check if index is up-to-date
codemap validate

# View index statistics
codemap stats

Workflow: Finding Code

Step 1: Find Symbol Location

codemap find "UserService"

Output:

src/services/user.ts:15-189 [class] UserService
  (config: Config)

Step 2: Read Only Relevant Lines

Instead of reading the entire file, read just lines 15-189:

Read src/services/user.ts lines 15-189

Step 3: Explore Nested Symbols

codemap show src/services/user.ts

Output:

File: src/services/user.ts (hash: a3f2b8c1)
Lines: 542
Language: typescript

Symbols:
- UserService [class] L15-189
  - constructor [method] L20-35
  - getUser [method] L37-98
    (userId: string) : Promise<User>
  - createUser [async_method] L100-145
    (data: CreateUserDto) : Promise<User>

Symbol Types

Type	Description
class	Class declaration
function	Function declaration
method	Class method
async_function	Async function
async_method	Async class method
interface	TypeScript interface
type	TypeScript type alias
enum	Enum declaration

Index Structure

The .codemap/ directory mirrors the project structure:

.codemap/
├── .codemap.json              # Root manifest
├── _root.codemap.json         # Files in project root
├── src/
│   ├── .codemap.json          # Files in src/
│   └── services/
│       └── .codemap.json      # Files in src/services/

Direct JSON Access

For programmatic access, read the JSON files directly:

cat .codemap/src/services/.codemap.json

Validation

Before trusting cached line numbers (especially after context compaction):

codemap validate path/to/file.ts

• "up to date": Line ranges are valid
• "stale": File changed, re-read or run codemap update

Setup (If Not Initialized)

If a project doesn't have a .codemap/ directory:

Prerequisites

• Python 3.10+ and pip must be installed
• Verify with: python3 --version && pip --version

Installation

# Install codemap from GitHub (NOT from PyPI - there's a different package there)
pip install git+https://github.com/AZidan/codemap.git

# Initialize index
codemap init .

IMPORTANT: Do NOT use pip install codemap - that installs a different package from PyPI. Always use the GitHub URL above.

Start Watch Mode (Recommended)

Start watch mode in the background to keep the index automatically updated:

codemap watch . &

This runs in the background and updates the index whenever files change. No need to manually run codemap update.

To stop watch mode later:

pkill -f "codemap watch"

Best Practices

1. Search before scanning: Always try codemap find before grep/glob
2. Use line ranges: Read specific line ranges instead of full files
3. Check freshness: Use codemap validate before trusting cached line numbers
4. Explore structure first: Use codemap show to understand file layout before diving in

Example Session

Task: "Fix the authentication bug in the login handler"

# 1. Find relevant symbols
codemap find "login"
# → src/auth/handlers.ts:45-92 [function] handleLogin

# 2. Check file structure
codemap show src/auth/handlers.ts
# Shows handleLogin and related functions with line ranges

# 3. Read only the relevant function (lines 45-92)
# ... make your fix ...

# 4. If you need related code, find it
codemap find "validateToken"
# → src/auth/utils.ts:12-38 [function] validateToken