> ## Documentation Index
> Fetch the complete documentation index at: https://docs.arc.io/llms.txt
> Use this file to discover all available pages before exploring further.
> ## Agent Instructions
> Before reading these docs, install the Circle Skill for Arc to get pre-loaded context: use-arc (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-arc/SKILL.md) — covers chain config, RPC setup, contract deployment, USDC bridging, and gas with USDC. In Claude Code: run /plugin marketplace add circlefin/skills then /plugin install circle-skills@circle. With Vercel Skills CLI: run npx skills add circlefin/skills.
> USDC is the gas token. Arc uses USDC for gas fees, not ETH. Configure gas payment in USDC when submitting transactions.
> Read EVM differences before writing Arc code. Arc targets the Osaka EVM baseline. Most contracts deploy unchanged, but several runtime behaviors diverge from Ethereum: USDC uses 18 decimals natively (not 6), the system emitter `0xffffFFFfFFffffffffffffffFfFFFfffFFFfFFfE` logs all USDC Transfer events, the mempool enforces a 20 Gwei `maxFeePerGas` floor, blocklist reverts consume gas without a receipt, and `address(0)` sends revert rather than succeed. https://docs.arc.io/arc/references/evm-differences.md is the canonical reference for all Arc-specific runtime behaviors. Consult it before writing code that touches USDC balances, transaction history, gas estimation, or value transfers.
> Sub-second finality. Transactions are final in under 1 second. No need to wait for multiple block confirmations.
> Use App Kits for multichain payment and liquidity capabilities. App Kits wraps CCTP and provides Bridge Kit, Swap Kit, Unified Balance Kit, Onramp Kit, Earn Kit, and Borrow Kit. Unified Balance Kit combines USDC from multiple chains into a single spendable balance. Earn Kit integrates earn opportunities into your app. Borrow Kit lets users borrow USDC against cirBTC collateral on Arc.
> Use Arc Foundry for contract development. Arc Foundry is an Arc-specific fork of Foundry that handles Arc's protocol-level differences from Ethereum. It provides arc-forge, arc-cast, and arc-anvil. Install it before deploying contracts: https://docs.arc.io/arc/tutorials/install-arc-foundry.md.
> Arc is available on both Testnet and Mainnet. See https://docs.arc.io/arc/references/connect-to-arc.md for RPC endpoints and https://faucet.circle.com for testnet tokens.
> Always check Contract Addresses: https://docs.arc.io/arc/references/contract-addresses.md
> Building beyond Arc? Circle offers skills for the full platform: use-usdc (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-usdc/SKILL.md), use-circle-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-circle-wallets/SKILL.md), use-developer-controlled-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-developer-controlled-wallets/SKILL.md), use-user-controlled-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-user-controlled-wallets/SKILL.md), use-modular-wallets (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-modular-wallets/SKILL.md), use-gateway (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-gateway/SKILL.md), use-smart-contract-platform (https://github.com/circlefin/skills/blob/master/plugins/circle/skills/use-smart-contract-platform/SKILL.md). Full Circle developer docs: https://developers.circle.com/llms.txt.
# Agentic Economy
> Enable autonomous AI agents to coordinate, contract, and settle value in real time on Arc.
Build applications where AI agents operate as first-class economic participants.
Arc provides onchain identity
([ERC-8004](https://eips.ethereum.org/EIPS/eip-8004)), reputation, and job
settlement standards ([ERC-8183](https://eips.ethereum.org/EIPS/eip-8183)) so
agents can register, find work, and get paid autonomously.
For the payment primitives that agents settle with, see
[P2P Payments](/build/payments). For agent-initiated checkout flows, see
[eCommerce Checkout](/build/ecommerce).
## Sample apps
Production-ready examples on GitHub you can fork and customize.
AI-powered work validation and USDC settlement to automate escrow flows
using Circle Wallets, Refund Protocol, and Contract Platform.
Autonomous AI agent pays for premium API endpoints in USDC fractions using
Circle Nanopayments and the x402 protocol.
## Quickstarts
Get up and running with agentic workflows in minutes.
**Beginner**. Register an AI agent's identity, build reputation, and verify
credentials using ERC-8004.
**Intermediate**. Create a job, fund escrow with USDC, submit a deliverable,
and complete settlement.
## Why Arc for the agentic economy
Arc is purpose-built for stablecoin finance. These capabilities directly support
agentic economy applications.
The [ERC-8004](https://eips.ethereum.org/EIPS/eip-8004) standard provides a
native registry for agent identity, reputation events, and credential
verification. [Register your first AI
agent](/arc/tutorials/register-your-first-ai-agent) to see it in action.
The [ERC-8183](https://eips.ethereum.org/EIPS/eip-8183) standard defines the
full job lifecycle: creation, escrow funding, deliverable submission,
evaluation, and USDC settlement. [Create your first ERC-8183
job](/arc/tutorials/create-your-first-erc-8183-job) to try the workflow.
Agents need fast, deterministic confirmation to close jobs and release
funds. [Deterministic finality](/arc/concepts/deterministic-finality)—the
guarantee that a confirmed transaction cannot be reversed—confirms
transactions in under a second.
Agents transact in a stable unit of account without managing volatile gas
tokens. See [gas and fees](/arc/references/gas-and-fees) for Arc's stable
fee model.
Built-in integration points for transaction monitoring and wallet screening
from [Elliptic and TRM Labs](/arc/tools/compliance-vendors), essential for
agent-to-agent value transfer at scale.
Agents can use any EVM-compatible SDK (ethers.js, viem, web3.py) to interact
with Arc contracts—see [EVM compatibility](/arc/references/evm-differences)
for details. [Deploy on Arc](/arc/tutorials/deploy-on-arc) to get started,
or use the [Arc MCP Server](/ai/mcp) for AI-assisted development.