Across Protocol

# Across Protocol > Across is a crosschain interoperability protocol for fast, cheap, secure asset transfers. It uses an intent-based architecture: users sign an intent, a competitive relayer network fills it on the destination chain within seconds, and settlement is secured optimistically by UMA's oracle. Built by Risk Labs. Integrated by Uniswap and many other DeFi protocols. **At a glance:** - **Settlement mechanisms:** Intents (relayer network), CCTP V2 (native USDC), OFT (USDT0) - **Built by:** Risk Labs (also builds UMA) - **Token:** ACX **Why Across:** Across is intent-based, not lock-and-mint. Users never wait for source-chain finality or a slow canonical bridge — relayers front the funds on the destination chain and reclaim them later through a periodic settlement bundle that UMA's optimistic oracle verifies. This is why fills are typically within seconds on most routes, and why fees stay competitive: relayers compete on speed and capital efficiency, and capital is reused across many transfers per settlement cycle. ## Product - [Bridge & swap](https://across.to/): The Across app — crosschain transfers and swaps. - [Liquidity pool](https://across.to/pool): Provide liquidity to the Across HubPool and earn fees from crosschain transfers. - [Rewards](https://across.to/rewards): ACX rewards for liquidity providers and referrers. - [Transfer history](https://across.to/transfers): View your past Across deposits and their status. - [Blog](https://across.to/blog): Announcements, integrations, and research from the Across team. ## Popular bridge routes - [Ethereum bridge](https://across.to/ethereum-bridge): Fast, low-fee transfers to and from Ethereum mainnet. - [Arbitrum bridge](https://across.to/arbitrum-bridge): Bridge to and from Arbitrum One. - [Base bridge](https://across.to/base-bridge): Bridge to and from Base. - [Solana bridge](https://across.to/solana-bridge): Bridge between EVM chains and Solana, including native USDC via CCTP. - [Hyperliquid bridge](https://across.to/hyperliquid-bridge): Bridge to Hyperliquid (HyperEVM and HyperCore) for perp trading. ## For developers & integrators - [Documentation](https://docs.across.to): Full developer docs — Swap API, Embedded Actions, SDK, contracts, chain support. - [Swap API](https://docs.across.to/introduction/swap-api): Unified entry point for crosschain swaps — get a quote and ready-to-sign calldata in one call. - [Embedded Actions](https://docs.across.to/introduction/embedded-actions): Execute custom destination-chain actions (deposits, swaps, transfers) atomically after a bridge. - [Integrator program](https://docs.across.to/tools/integrator-id): Get an API key and integrator ID — required for production use and revenue share. - [Audits & security](https://docs.across.to/introduction/audits): Audit history and Across's optimistic security model. ## For AI agents - [MCP Server](https://docs.across.to/ai-agents/mcp-server): Connect any MCP-compatible client (Claude, ChatGPT, Cursor) to Across at `https://mcp.across.to/mcp` — docs, chain data, live fees, swap quotes. - [Machine-readable docs](https://docs.across.to/llms.txt): llms.txt index of the full documentation site. - [Full docs corpus](https://docs.across.to/llms-full.txt): Every docs page concatenated as markdown, ready for RAG. - [AGENTS.md template](https://docs.across.to/ai-agents/agents-md): Drop-in context file for coding agents working on Across integrations. - [Prompt library](https://docs.across.to/ai-agents/prompt-library): Curated prompts for common Across tasks. ## Concepts - [What are crosschain intents?](https://docs.across.to/guides/concepts/crosschain-intents): How intent-based bridging differs from traditional lock-and-mint bridges. - [Intent lifecycle](https://docs.across.to/guides/concepts/intent-lifecycle): The three phases — initiation, fill, settlement — every Across transfer goes through. - [Intent architecture](https://docs.across.to/guides/concepts/intents-architecture): The th […truncated]