Quickstart

Welcome to CSC!

This quickstart guide will have you using AI-powered coding assistance in a few minutes. By the end, you'll understand how to use CSC for common development tasks.

Before you begin

Make sure you have:

• A terminal or command prompt open
• A code project to work with
• A CoStrict account

Step 1: Install CSC

Install globally from npm

npm install -g @costrict/csc --registry=https://registry.npmjs.org/

After installation, you can use the csc command.

Step 2: Start your first session

Open your terminal in any project directory and start CSC:

cd /path/to/your/project
csc

You'll see the CSC welcome screen with your session information, recent conversations, and latest updates. Type /help for available commands or /resume to continue a previous conversation.

Step 3: Log in to your account

CSC requires an account to use. When you start an interactive session with the csc command, you'll need to log in:

csc
# You'll be prompted to log in on first use

/login
# Follow the prompts to log in with your account

You can log in using any of these account types:

• CoStrict (recommended)
• Custom provider

Option 1: CoStrict Enterprise Login (Recommended)

Once logged in, your credentials are stored and you won't need to log in again. To switch accounts later, use the /login command.

Option 2: Third-Party API Direct Connection

Fill in information in the UI

For individual users or self-hosted API services. Select CoStrict Compatible / OpenAI / Gemini, and fill in the following:

Field	Description	Example
Base URL	API service URL	https://api.example.com/v1
API Key	Authentication key	sk-xxx
Haiku Model	Fast model	claude-haiku-4-5-20251001
Sonnet Model	Balanced model	claude-sonnet-4-6
Opus Model	High-performance model	claude-opus-4-6

You can also edit the config file directly

Skip the interactive login and edit ~/.costrict/settings.json directly:

{
  "env": {
    "ANTHROPIC_BASE_URL": "https://api.example.com/v1",
    "ANTHROPIC_AUTH_TOKEN": "sk-xxx",
    "ANTHROPIC_DEFAULT_HAIKU_MODEL": "claude-haiku-4-5-20251001",
    "ANTHROPIC_DEFAULT_SONNET_MODEL": "claude-sonnet-4-6",
    "ANTHROPIC_DEFAULT_OPUS_MODEL": "claude-opus-4-6"
  }
}

Private Deployment

Private deployment requires the following configuration:

• For CLI usage, set the COSTRICT_BASE_URL environment variable before starting
• After authentication, credentials are stored at ~/.costrict/share/auth.json, which takes priority for server configuration

Step 4: Model selection

> /model  # Start switching models

Step 5: Ask your first question

Let's start with understanding your codebase. Try one of these commands:

what does this project do?

CSC will analyze your files and provide a summary. You can also ask more specific questions:

what technologies does this project use?

where is the main entry point?

explain the folder structure

You can also ask CSC about its own capabilities:

what can CSC do?

how do I create custom skills in CSC?

can CSC work with Docker?

Note: CSC reads your project files as needed. You don't have to manually add context.

Step 6: Make your first code change

Now let's make CSC do some actual coding. Try a simple task:

add a hello world function to the main file

CSC will:

1. Find the appropriate file
2. Show you the proposed changes
3. Ask for your approval
4. Make the edit

Note: CSC always asks for permission before modifying files. You can approve individual changes or enable "Accept all" mode for a session.

Step 7: Use Git with CSC

CSC makes Git operations conversational:

what files have I changed?

commit my changes with a descriptive message

You can also prompt for more complex Git operations:

create a new branch called feature/quickstart

show me the last 5 commits

help me resolve merge conflicts

Step 8: Fix a bug or add a feature

CSC is proficient at debugging and feature implementation.

Describe what you want in natural language:

add input validation to the user registration form

Or fix existing issues:

there's a bug where users can submit empty forms - fix it

CSC will:

• Locate the relevant code
• Understand the context
• Implement a solution
• Run tests if available

Step 9: Test out other common workflows

There are a number of ways to work with CSC:

Refactor code

refactor the authentication module to use async/await instead of callbacks

Write tests

write unit tests for the calculator functions

Update documentation

update the README with installation instructions

Code review

review my changes and suggest improvements

💡 Tip: Talk to CSC like you would a helpful colleague. Describe what you want to achieve, and it will help you get there.

Essential commands

Here are the most important commands for daily use:

Command	What it does	Example
csc	Start interactive mode	csc
csc "task"	Run a one-time task	csc "fix the build error"
csc -p "query"	Run one-off query, then exit	csc -p "explain this function"
csc -c	Continue most recent conversation in current directory	csc -c
csc -r	Resume a previous conversation	csc -r
/clear	Clear conversation history	/clear
/help	Show available commands	/help
exit or Ctrl+D	Exit CSC	exit

See the CLI reference for a complete list of commands.

Pro tips for beginners

For more, see best practices and common workflows.

Be specific with your requests

Instead of: "fix the bug"

Try: "fix the login bug where users see a blank screen after entering wrong credentials"

Use step-by-step instructions

Break complex tasks into steps:

1. create a new database table for user profiles
2. create an API endpoint to get and update user profiles
3. build a webpage that allows users to see and edit their information

Let CSC explore first

Before making changes, let CSC understand your code:

analyze the database schema

build a dashboard showing products that are most frequently returned by our UK customers

Save time with shortcuts

• Press ? to see all available keyboard shortcuts
• Use Tab for command completion
• Press ↑ for command history
• Type / to see all commands and skills