Online Judge MCP Server

This is a Model Context Protocol (MCP) server that provides AI agents with tools to interact with an Online Judge API.

Features

Provides the following tools:

• list_problems(offset, limit): List available problems on the OJ.
• list_my_submissions(offset, limit): List recent submissions made by the authenticated user.
• get_problem_details(problem_id): Fetch detailed descriptions, samples, limits, and rules of a problem.
• submit_code(problem_id, code, language): Submit source code to a specific problem.
• get_submission_status(submission_id): Check the polling status of a code submission.

Requirements

• Python 3.10 or higher
• uv (recommended) or pip

Setup & Running

1. Install dependencies:

   pip install -e .
   

2. Run the MCP server locally: Set the following environment variables before running:

   set OJ_URL="http://localhost:8000" # Replace with actual OJ URL
   set OJ_USERNAME="your-username"
   set OJ_PASSWORD="your-password"
   
   oj-mcp-server
   

Installation in MCP Clients

To use this server with an MCP-compatible client like Claude Desktop, Cursor, or Cline, you need to add it to your client's MCP configuration settings.

Claude Desktop

Edit your claude_desktop_config.json:

{
  "mcpServers": {
    "oj-mcp-server": {
      "command": "uv",
      "args": [
        "--directory",
        "c:/dev/oj-mcp-server",
        "run",
        "oj-mcp-server"
      ],
      "env": {
        "OJ_URL": "http://localhost:8000",
        "OJ_USERNAME": "your-username",
        "OJ_PASSWORD": "your-password"
      }
    }
  }
}

Cursor / Cline

In the MCP settings panel, add a new server:

• Type: command
• Name: oj-mcp-server
• Command: uv --directory c:/dev/oj-mcp-server run oj-mcp-server (or the direct path to the python executable if installed via pip)
• Environment: Set OJ_URL, OJ_USERNAME, and OJ_PASSWORD

(Make sure to adjust the directory path to wherever you cloned the repository)

OpenCode

To configure the MCP server in the OpenCode IDE, you can edit your opencode.json configuration file (located globally at ~/.config/opencode/opencode.json or in your project directory). Add the server under the mcp key:

{
  "mcp": {
    "oj-mcp-server": {
      "type": "local",
      "command": [
        "uv",
        "--directory",
        "c:/dev/oj-mcp-server",
        "run",
        "oj-mcp-server"
      ],
      "environment": {
        "OJ_URL": "http://localhost:8000",
        "OJ_USERNAME": "your-username",
        "OJ_PASSWORD": "your-password"
      }
    }
  }
}