Across Developer DocumentationAI Agents
Give your AI agent crosschain superpowers with a single command.
Add Across to your agent with one command
npx skills add https://github.com/across-protocol/skills --yesCompatible with Claude Code, Codex, Cursor, Openclaw, and more.
Connect to the Across MCP Server
https://mcp.across.to/mcpAdd this URL to any MCP-compatible client — Claude Desktop, Claude Code, Cursor, VS Code Copilot, Windsurf, Codex.
What your agent gets
Once installed, your AI agent can:
- Bridge tokens across 23+ chains with natural language commands
- Get live quotes — fees, estimated fill times, and optimal routes
- Execute crosschain swaps — USDC, USDT, WETH, and more
- Track deposits — check fill status and confirmations in real time
- Compose embedded actions — bridge + swap + deposit into DeFi in one transaction
Supported Agents
| Agent Framework | Status |
|---|---|
| Claude Code | Supported |
| Codex | Supported |
| Cursor | Supported |
| Openclaw | Supported |
Two ways to connect
| Approach | Best for | Setup |
|---|---|---|
Skills CLI (npx skills add) | Claude Code, Codex, Cursor, Openclaw | One command — installs tool definitions directly into your agent config |
| MCP Server | Claude Desktop, Cursor, Windsurf, VS Code Copilot, Codex | Point your client at https://mcp.across.to/mcp — search docs, query chains, get live bridge fees |
Use both together or pick whichever fits your workflow.
Supported Chains
Across currently supports 26 mainnet chains:
| Chain | Chain ID | Chain | Chain ID |
|---|---|---|---|
| Ethereum | 1 | Arbitrum | 42161 |
| Optimism | 10 | Base | 8453 |
| Polygon | 137 | BNB Smart Chain | 56 |
| zkSync | 324 | Linea | 59144 |
| Scroll | 534352 | Blast | 81457 |
| Mode | 34443 | Lisk | 1135 |
| Zora | 7777777 | Ink | 57073 |
| Unichain | 130 | Soneium | 1868 |
| World Chain | 480 | Lens | 232 |
| Lighter | 2337 | Tempo | 4217 |
| HyperCore | 1337 | HyperEVM | 999 |
| MegaETH | 4326 | Monad | 143 |
| Plasma | 9745 | Solana | 34268394551451 |
For contract addresses and explorer links, see the Chains & Contracts page. For the live list, query the /swap/chains endpoint.
How it works
The skills package provides your agent with structured tool definitions that map directly to the Across Swap API. Your agent receives:
- Chain discovery — query supported chains and tokens
- Quote generation — get executable calldata for any crosschain transfer
- Transaction execution — approval and bridge transaction helpers
- Status tracking — monitor deposits until they're filled
The agent handles the entire flow autonomously — from selecting the right route to executing the transaction.
Example prompt
Once the skill is installed, you can simply tell your agent:
Bridge 100 USDC from Arbitrum to BaseThe agent will discover chains, look up token addresses, fetch a quote, handle approvals, and execute the bridge — all without any additional code.
Explore
MCP Server
Search docs, query chains, and get live bridge fees from any MCP-compatible client. Hosted at mcp.across.to.
Machine-Readable Docs
Feed Across documentation to agents and RAG pipelines via llms.txt endpoints.
AGENTS.md Template
Drop-in AGENTS.md for repos integrating Across — gives coding agents full context.
Prompt Library
Curated prompts for discovery, quoting, execution, tracking, and DeFi composition.
Agent Workflows
End-to-end examples showing real agent sessions performing crosschain tasks.