MonAgent

Give an AI agent a wallet that can pay, build trust and hire other agents on Monad, without it ever holding a private key.

MonAgent is a plugin for the MetaMask Agent Wallet (mm CLI), built for the Monad Metropolis Hackathon track Best Agent Wallet Plugin. It adds agent-to-agent commerce on Monad mainnet (143) and testnet (10143): payments, on-chain identity and reputation, paid API calls, and escrow. Every transaction and signature is executed and policy-checked by MetaMask.

npm install -g @metamask/agent-wallet@7
mm config set experimentalPlugins true
mm config set experimentalAllowUnverifiedInstalls true
mm plugins install @zakyirsyaad/monagent-plugin --accept-permissions
mm monad identity get 1 --chain-id 143        # read an agent's on-chain identity, no login needed

Why

• Agents need to move money, but shouldn't hold keys. MonAgent never touches keys. It builds a transaction and hands it to MetaMask, which applies its policy engine and can ask a human to approve.
• Agents need to decide whom to trust. Identity and reputation use the official ERC-8004 registries on Monad, so an agent can check a counterparty's track record before paying it.
• Agents buy and sell tool calls. Paid APIs answering 402 Payment Required are paid through x402 with a signed USDC authorization, within a spending limit you set.
• Agents subcontract work. A small escrow contract holds a bounty until the client releases it.

What an agent can do

Quickstart

You need Node.js 22+ and @metamask/agent-wallet 6.2+ or 7.x.

npm install -g @metamask/agent-wallet@7
mm config set experimentalPlugins true
mm config set experimentalAllowUnverifiedInstalls true
mm plugins install @zakyirsyaad/monagent-plugin --accept-permissions

mm monad reputation check 1 --chain-id 143    # reads need no login or funds
mm login                                      # once, before any write
mm init                                       # first run only

Every command takes --chain-id 10143|143 (default 10143) and --json for machine-readable output. Writes need MON for gas on the chain you write to; use mainnet (see Status and limits).

Example: check, pay, rate

# 1. Is this agent trustworthy? (read-only; trust tier is HIGH, MEDIUM, LOW or UNRATED)
mm monad reputation check 1 --chain-id 143

# 2. Pay it (mainnet moves real funds)
mm monad pay --to 0x<agent wallet> --amount 5 --token USDC --chain-id 143

# 3. Leave feedback once the work is done (-100 to 100; you can't rate your own agent)
mm monad reputation give --agentId 1 --value 90 --tag1 quality --chain-id 143

The full command list, with every flag, is in REFERENCE.md.

Use with AI agents

Any agent that can run shell commands can call mm monad … --json. Three packages make that easier:

None of them holds keys. They run on the machine where mm is installed and signed in, and a person still approves writes. Details, tool names and the MCP safety behavior are in REFERENCE.md.

The Claude Code plugin also ships four named workflow agents, each with its own skill and slash command and the same guardrails (read first, confirm before every write, explicit chain, no blind retries, stop on [AWAITING_MFA]):

There is deliberately no escrow or hiring workflow: escrow writes need testnet, and MetaMask currently rejects testnet writes (see Status and limits).

How it works

flowchart LR
  A[AI agent] -->|"mm monad … --json"| H[MetaMask Agent Wallet CLI]
  A -->|MCP tools| K[monagent-mcp]
  K -->|"runs mm, no shell"| H
  H -->|restricted context| P[MonAgent plugin]
  P -->|reads| R[(Monad RPC)]
  P -->|tx / EIP-712 request| E[MetaMask wallet executor]
  E -->|policy check + approval| E
  E -->|signed tx| M[(Monad 143 / 10143)]
  P -->|EIP-3009 authorization| S[x402 server]

The plugin builds a transaction or an EIP-712 payload, and MetaMask decides whether to sign it. Along the way it enforces a few rules:

• Testnet by default, and any chain other than 10143 or 143 is rejected before anything is signed.
• x402 signs exactly what it checked. It accepts one payment requirement on the requested chain, enforces your --maxSpend, then verifies the signer matches --payer before sending anything.
• Only the client can release or refund an escrow job; the worker can't pay itself.

Status and limits

MonAgent is early (0.x). What to know before you rely on it:

• Reads work on both chains; use mainnet for writes. With @metamask/agent-wallet 7.0.0, MetaMask's wallet service answers Invalid chainId for writes on Monad testnet, so they wait on Submitting... and nothing is sent. This is a MetaMask service limit that the plugin can't work around.
• Escrow exists only on testnet, so mm monad jobs … can't complete a write through MetaMask today. The contract is covered by Foundry tests and contract simulation tests in this repo.
• A person is always in the loop for writes: mm login and mm init once, and each write can stop at [AWAITING_MFA] until approved in MetaMask.
• --walletAddress (identity) and --memo (payments) aren't stored on-chain.

Reference

REFERENCE.md has the networks and contract addresses, every command with its flags, the AI agent integrations in detail, and troubleshooting. The agent-facing guide is skills/monad-agent/SKILL.md.

Development

npm install
npm run typecheck
npm test                                           # runs all suites (workspaces, scripts, simulation)
npm run test:all                                   # alias for npm test
npm test --workspace @zakyirsyaad/monagent-plugin  # test plugin directly
npm test --workspace @zakyirsyaad/monagent-mcp     # test MCP server directly
node --test scripts/*.test.mjs                     # repo and packaging guards
(cd contracts && forge test)                       # Foundry contract tests

packages/plugin-monad/   the mm plugin
packages/mcp-monad/      MCP server that wraps the mm CLI
claude-plugin/           Claude Code plugin (workflow agents, slash commands, workflow skills, .mcp.json)
.claude-plugin/          Claude Code marketplace manifest
contracts/               MonadA2AEscrow + Foundry tests
skills/monad-agent/      shared agent skill (SKILL.md), synced into claude-plugin/ and the npm package;
                         the four workflow skills are sourced in claude-plugin/skills/ only
scripts/                 deploy, demo and repo checks

npm run demo:local walks through the main flows against a mocked host and prints placeholder transaction hashes; use the mm commands above for a real demonstration.

License

MIT © 2026 Zaky Irsyad Rais

{
  "$schema": "https://anthropic.com/claude-code/marketplace.schema.json",
  "name": "monagent-marketplace",
  "description": "MonAgent plugins for Claude Code",
  "owner": {
    "name": "Zaky Irsyad Rais"
  },
  "plugins": [
    {
      "name": "monagent",
      "description": "MetaMask Agent Wallet Plugin for Monad A2A Commerce & Trust (ERC-8004 & x402)",
      "version": "0.3.0",
      "author": {
        "name": "Zaky Irsyad Rais"
      },
      "source": "./claude-plugin"
    }
  ]
}