Myth

Myth auto-generates Model Context Protocol (MCP) servers for Celo smart contracts. Give it a verified contract address and it fetches the ABI from Blockscout, maps every function and event to an MCP tool, and launches a server your AI agent can call.

Built for Celo's agent-friendly properties: sub-cent gas, fast finality, and stablecoin gas payment via feeCurrency.

Open source under MIT. Contributions welcome — see CONTRIBUTING.md.

Architecture

[Contract Address] → [Blockscout ABI] → [ABI → Zod/JSON Schema] → [MCP Server]
         ↓
 [EIP-1967 Proxy Resolver] → implementation ABI

| Step | Module | What it does | |------|--------|--------------| | 1 | blockscout.ts | GET ?module=contract&action=getabi&address={addr} | | 2 | abi-to-zod.ts | Maps Solidity types → Zod validators + JSON Schema | | 3 | abi-events.ts | Generates query event tools from ABI events | | 4 | celo-tx.ts | Attaches feeCurrency on write txs (pay gas in cUSD/USDT) | | 5 | create-server.ts | Wires tools into @modelcontextprotocol/sdk | | 6 | registry.ts | Multi-contract registry at ~/.myth/registry.json |

Install

# Global CLI
npm install -g @gideondern/myth-celo-mcp

# Or run without installing
npx -y --package @gideondern/myth-celo-mcp myth --help

npm: https://www.npmjs.com/package/@gideondern/myth-celo-mcp

Quick Start

# Infra workflow: add → list → serve
myth add -a 0x765DE816845861e75A25fCA122bb6898B8B1282a -n celo-mainnet --alias cusd
myth list
myth serve   # serves registry (uses ~/.myth/cache for fast restarts)

# Single contract without registry
myth serve -a 0x765DE816845861e75A25fCA122bb6898B8B1282a -n celo-mainnet

# HTTP transport (for remote agents)
myth serve -a 0x765DE816845861e75A25fCA122bb6898B8B1282a -n celo-mainnet --http --port 3100

# Generate a standalone package with manifest + Cursor config
myth generate -a 0x765DE816845861e75A25fCA122bb6898B8B1282a -n celo-mainnet -o ./generated/cusd

Registry & ABI cache

Contracts live in ~/.myth/registry.json. ABIs are cached in ~/.myth/cache/<network>/ (24h TTL).

myth add -a 0x765DE816845861e75A25fCA122bb6898B8B1282a -n celo-mainnet --alias cusd
myth list
myth sync cusd --force   # refresh ABI from Blockscout
myth remove cusd
myth serve               # all registry contracts (cache-first)
myth serve --http        # HTTP transport

Tools are prefixed by alias: cusd_balanceOf, cusd_event_Transfer, etc.

Cursor Integration

Add to ~/.cursor/mcp.json (already configured if you used the setup step):

{
  "mcpServers": {
    "myth-cusd": {
      "command": "npx",
      "args": [
        "-y",
        "--package",
        "@gideondern/myth-celo-mcp",
        "myth",
        "serve",
        "-a",
        "0x765DE816845861e75A25fCA122bb6898B8B1282a",
        "-n",
        "celo-mainnet"
      ],
      "env": {
        "MYTH_FEE_CURRENCY": "cUSD"
      }
    }
  }
}

Serve every contract in your registry (~/.myth/registry.json):

{
  "mcpServers": {
    "myth-registry": {
      "command": "npx",
      "args": ["-y", "--package", "@gideondern/myth-celo-mcp", "myth", "serve", "--registry"]
    }
  }
}

Reload Cursor MCP after saving. For write tools, add MYTH_PRIVATE_KEY to env.

Built-in Meta Tools

Every server includes:

| Tool | Description | |------|-------------| | myth_contract_info | Contract addresses, networks, tool counts | | myth_fee_currencies | Available stablecoins per network for gas |

Networks

| Network | Blockscout API | Default RPC | |---------|----------------|-------------| | celo-mainnet | https://celo.blockscout.com/api | https://forno.celo.org | | celo-sepolia | https://celo-sepolia.blockscout.com/api | https://forno.celo-sepolia.celo-testnet.org |

Environment Variables

| Variable | Description | |----------|-------------| | MYTH_CONTRACT_ADDRESS | Target contract | | MYTH_NETWORK | celo-mainnet or celo-sepolia | | MYTH_RPC_URL | Override RPC endpoint | | MYTH_PRIVATE_KEY | Wallet for write transactions | | MYTH_FEE_CURRENCY | Stablecoin for gas (cUSD, USDT, or 0x...) | | MYTH_REGISTRY_PATH | Registry file (default: ~/.myth/registry.json) | | MYTH_BLOCKSCOUT_API_KEY | Optional Blockscout PRO API key |

Programmatic API

import {
  fetchContractAbi,
  abiToMcpTools,
  launchMythServer,
  launchHttpServer,
  addToRegistry,
} from "@gideondern/myth-celo-mcp";

await launchMythServer({
  contractAddress: "0x765DE816845861e75A25fCA122bb6898B8B1282a",
  network: "celo-mainnet",
  feeCurrency: "cUSD",
});

await launchHttpServer({
  config: { contractAddress: "0x...", network: "celo-mainnet" },
  port: 3100,
});

Development

git clone https://github.com/gideondern/myth-celo-mcp.git
cd myth-celo-mcp
npm install
npm run build
node dist/cli.js add -a 0x765DE816845861e75A25fCA122bb6898B8B1282a -n celo-mainnet --alias cusd
node dist/cli.js serve

References

• celo-mcp — Official Celo MCP server (Python)
• evm-mcp-server — Dynamic EVM tool patterns
• Blockscout Contract API

License

MIT © Gideon Dern