Sub Killer MCP Server

MCP server for Dead Subscription Killer — scan wallets, detect crypto subscriptions, manage approvals on Monad.

The first MCP server for blockchain subscription management.

What Is This?

An MCP (Model Context Protocol) server that lets AI agents (Claude, Cursor, Windsurf, etc.) scan wallets for forgotten token approvals and subscriptions on the Monad blockchain.

Use Cases

• "Scan my wallet for risky approvals" — agent calls scan_wallet
• "What is this spender address?" — agent calls identify_spender
• "How much would I save on Monad vs Ethereum?" — agent calls estimate_gas_savings
• "Do a security audit of my wallet" — agent uses security_audit prompt

Tools

Tool	Description
scan_wallet	Scan a wallet for active token approvals
identify_spender	Identify what a spender address is (protocol, category, risk)
get_known_protocols	List all known DeFi protocols with risk levels
check_allowance	Check allowance for specific token/spender
get_contract_stats	Get user stats from SubscriptionKiller contract
get_contract_subscriptions	Get subscriptions from contract
estimate_gas_savings	Compare gas costs Monad vs Ethereum
get_network_info	Get Monad network details

Resources

Resource	Description
sub-killer://protocols/all	Full known protocols database
sub-killer://protocols/categories	Protocol categories
sub-killer://network/testnet	Monad testnet config
sub-killer://network/mainnet	Monad mainnet config

Prompts

Prompt	Description
analyze_wallet	Comprehensive wallet analysis
security_audit	Security-focused approval audit
compare_networks	Gas cost comparison Monad vs Ethereum

Setup

Claude Desktop

Add to ~/Library/Application Support/Claude/claude_desktop_config.json:

{
  "mcpServers": {
    "sub-killer": {
      "command": "node",
      "args": ["/path/to/sub-killer-mcp/src/index.js"]
    }
  }
}

Cursor

Add to .cursor/mcp.json:

{
  "mcpServers": {
    "sub-killer": {
      "command": "node",
      "args": ["/path/to/sub-killer-mcp/src/index.js"]
    }
  }
}

With npx (after publishing)

{
  "mcpServers": {
    "sub-killer": {
      "command": "npx",
      "args": ["-y", "sub-killer-mcp"]
    }
  }
}

Install & Run

npm install
node src/index.js

Test

node src/test.js

Known Protocols Database

Includes 40+ known DeFi protocols across categories:

• DEX: Uniswap, SushiSwap, PancakeSwap, 1inch
• Lending: Aave, Compound
• Staking: Lido, Rocket Pool, Coinbase
• NFT: OpenSea, Blur
• Derivatives: dYdX, GMX
• Bridges: Base, Optimism, Arbitrum

Architecture

sub-killer-mcp/
├── src/
│   ├── index.js          # MCP server entry point
│   ├── test.js            # Test suite
│   ├── tools/
│   │   └── index.js       # Tool definitions & handlers
│   ├── lib/
│   │   └── scanner.js     # Blockchain scanner (viem)
│   └── data/
│       └── protocols.js   # Known protocols DB
├── package.json
└── README.md

Why Monad?

Metric	Ethereum	Monad
Gas per tx	$20-50	$0.001
Finality	12 min	<1s
TPS	15	10,000

Batch-cancelling 10 subscriptions costs ~$300 on Ethereum. On Monad: $0.01.

License

MIT