JustIn Code (justincode)

JustIn Code is a terminal app that lets you talk to an AI assistant for help with files, code, commands, MCP tools, and web search.

What is it?

• You open it in a terminal with the justincode command.
• You type requests in normal language.
• It uses the AI model you configure in justincode.json.
• Web search, MCP servers, and skills are optional extras.

Requirements

• Node.js 20 or newer
• npm
• A normal interactive terminal window
• An API key for an AI model provider
• Optional: a web search API key if you want live web results

Install

npm install -g justin-code

Start the app:

justincode

Quick check:

justincode --help

The first time you run it, the app creates the settings file and shows its location. Usually:

• Windows: C:\Users\YOUR_NAME\.config\justincode\justincode.json
• macOS/Linux: ~/.config/justincode/justincode.json

Set up justincode.json

Open the existing justincode.json file and change only the values you need. Do not delete the rest of the file.

Add your model key

Choose the model you want in models.selected, then paste your key into the matching provider apiKey.

Example:

"models": {
  "selected": "openai/gpt-4o-mini",
  "providers": {
    "openai": {
      "options": {
        "baseURL": "https://api.openai.com/v1",
        "apiKey": "PASTE_YOUR_OPENAI_KEY_HERE"
      },
      "models": {
        "gpt-5.2": {
          "name": "gpt-5.2"
        },
        "gpt-4o-mini": {
          "name": "gpt-4o-mini"
        }
      }
    }
  }
}

This follows the same structure the app already uses in justincode.json.

If you use another provider, add your key to that provider and set selected to provider/model. Keep the rest of the JSON structure as it is.

Add your web search key

Web search is optional. If you want it, set the provider name in webSearch.selected and paste the API key for that provider.

Example:

"webSearch": {
  "selected": "tavily",
  "providers": {
    "tavily": {
      "apiKey": "PASTE_YOUR_TAVILY_KEY_HERE"
    }
  }
}

Add MCP servers

MCP servers give the agent extra tools.

Example using the k8s-port-forward MCP server:

"mcp": {
  "enabled": true,
  "servers": {
    "k8s-port-forward": {
      "command": "npx",
      "args": ["-y", "k8s-port-forward-mcp@latest"],
      "env": {},
      "disabled": false
    }
  }
}

Check the MCP server's documentation for its prerequisites (tools, auth, environment).

After saving, restart justincode or run /mcp reload so the agent loads the server. Then you can ask the agent to use its tools.

Add skills

Skills are small instruction files that teach the agent a specific job or workflow.

1. Create a folder inside one of these directories: ~/.agents/skills, ~/.justincode/skills, or .justincode/skills
2. Inside that folder, create a file named SKILL.md
3. Add the skill name to skills.active or enable it with /skills enable

Example skills config:

"skills": {
  "enabled": true,
  "directories": [
    "~/.agents/skills",
    "~/.justincode/skills",
    ".justincode/skills"
  ],
  "active": ["My Skill"]
}

Uninstall

npm uninstall -g justin-code

If you also want to remove your personal settings, delete the justincode.json file after uninstalling.