JSON in, JSON out. MCP-compatible. Single Rust binary. Built for LLMs, automation pipelines, and developers who think in JSON.
Quick Start · Commands · Agent mode · Create Protocol · MCP
Every blockchain CLI today is either a heavyweight toolkit (Foundry) or a chain-specific SDK bundle. Neither is built for agents. arbitrum-cli wraps Arbitrum RPC behind a clean surface that:
- Emits JSON by default so agents can pipe output anywhere
- Has a generic
execcommand for any RPC method - Exposes tools via MCP so Claude, Cursor, or any AI agent can call it natively
- Ships as a single Rust binary —
cargo install arbitrum-cliand go
Part of the agent-first blockchain CLI suite by kcolbchain.
cargo install arbitrum-cli
# Query the latest block (JSON output, agent-ready)
arbitrum-cli block latest
# Check an address balance
arbitrum-cli balance 0xC75020d5f669F5D15Afcb81b0e5F6d21bCDa9664
# Check a token balance (USDC on Arbitrum)
arbitrum-cli token \
0xaf88d065e77c8cC2239327C5EDb3A432268e5831 \
0xC75020d5f669F5D15Afcb81b0e5F6d21bCDa9664
# Get current gas price
arbitrum-cli gas
# Human-readable output
arbitrum-cli block latest --human| Command | What it does |
|---|---|
block <number|latest> |
Fetch block info |
tx <hash> |
Fetch transaction by hash |
balance <address> |
Native ETH balance |
token <token> <address> |
ERC-20 balance with decimals |
call --data <hex> <to> |
Read contract via eth_call |
gas |
Current gas price + block number |
watch blocks |
Stream new blocks (polling) |
exec <method> --params '[...]' |
Generic RPC passthrough |
agent-deposit <address> --action ... |
Create Protocol AgentDeposit — balance, deposit, withdraw, registered |
mcp |
Start MCP server for AI agents |
info |
List supported Arbitrum chains |
All commands default to JSON output. No flags, no ceremony — pipe it into jq, feed it to an LLM, or forward to any tool.
# Agent-friendly
arbitrum-cli balance 0xC750... | jq .balance_eth
# Generic RPC for agents — any method, any params
arbitrum-cli exec eth_chainId --params '[]'
arbitrum-cli exec eth_getLogs --params '[{"fromBlock":"latest","address":"0x..."}]'Use --human for colored terminal output when you're debugging.
Works out of the box with Create Protocol AgentDeposit on Arbitrum. Create Protocol is an AI agent economy where agents register, deposit USDC, execute tasks, and earn fees — arbitrum-cli is the tool an agent uses to see and move its own on-chain funds.
# How much USDC does this agent have on deposit?
arbitrum-cli agent-deposit 0xC75020d5f669F5D15Afcb81b0e5F6d21bCDa9664 --action balance
# Is this agent registered in Phase 1?
arbitrum-cli agent-deposit 0xC75020d5f669F5D15Afcb81b0e5F6d21bCDa9664 --action registered
# Prepare an unsigned deposit tx (1 USDC = 1_000_000 raw, 6 decimals).
# The CLI never holds keys — sign + broadcast externally.
arbitrum-cli agent-deposit 0xC750... --action deposit --amount 1000000
# Same shape for withdraw
arbitrum-cli agent-deposit 0xC750... --action withdraw --amount 500000The AgentDeposit contract address is resolved automatically per chain (Arbitrum One, Arbitrum Sepolia). Override with --contract 0x… for forks or staging deployments.
Phase 1 of Create Protocol is live on Sepolia with Arbitrum One redeployment imminent — see createprotocol.org.
Expose arbitrum-cli as a Model Context Protocol server so Claude, Cursor, or any MCP-compatible agent can call Arbitrum directly.
arbitrum-cli mcp --bind 127.0.0.1:3456Tools exposed:
arbitrum.block·arbitrum.tx·arbitrum.balance·arbitrum.tokenarbitrum.call·arbitrum.gas·arbitrum.exec
(MCP integration is stubbed in v0.1 — full stdio + SSE support in v0.2.)
# Use a custom RPC (env var)
export ARBITRUM_RPC_URL=https://arb-mainnet.g.alchemy.com/v2/YOUR_KEY
arbitrum-cli block latest
# Or pass inline
arbitrum-cli --rpc https://arb1.arbitrum.io/rpc gasDefault RPC: https://arb1.arbitrum.io/rpc (Arbitrum One)
| Tool | Purpose |
|---|---|
arbitrum-cli |
Arbitrum chain access |
superchain-trace |
OP Superchain cross-chain message debugger |
stylus-profiler |
Arbitrum Stylus WASM binary analyzer |
gas-oracle |
L2 gas cost prediction via blob fees |
MIT — do whatever you want. Attribution appreciated.
See kcolbchain.com/join. Good first issues welcome.