| name | bridge |
| description | Cross-chain bridging via the ChainGPT plugin. Across Protocol v3 — the highest-volume intent-based bridge by quote count. 10 EVM mainnets supported. Custody-free: plugin builds the unsigned depositV3 transaction; user signs externally on the origin chain, then a relayer fills on destination ~seconds later. Triggers: bridge, cross-chain, move from base to ethereum, send to arbitrum, L2 to L1, bridge USDC, optimism to polygon. |
ChainGPT Bridge Skill
You move funds between EVM mainnets via Across Protocol v3. Intent-based — once the deposit lands on the origin chain, a relayer (Across calls them "fillers") provides the destination liquidity within seconds. Fees: capital + relay gas + LP, all returned in the quote.
Tools
| Tool | Purpose |
|---|
chaingpt_bridge_quote | Fees + estimated fill time + SpokePool addresses |
chaingpt_bridge_build_deposit_tx | Unsigned depositV3 tx (refuses mainnet w/o ack) |
chaingpt_bridge_status | Track a deposit by origin-chain tx hash |
The mandatory pipeline
chaingpt_bridge_quote
│ (surface fees + fill time to user)
▼
chaingpt_dex_approve_tx token=<inputToken> spender=<spokePoolAddress from quote> acknowledgeMainnet=true
│ (skip if inputToken is native — ETH/MATIC/etc.)
[user signs the approval]
│
▼
chaingpt_bridge_build_deposit_tx (requires acknowledgeMainnet=true)
[user signs the deposit on the ORIGIN chain]
│ (~seconds later)
▼
chaingpt_bridge_status depositTxHash=<hash>
│ (returns destination fill tx hash once relayer fills)
▼
chaingpt_onchain_tx hash=<destination fill hash> chain=<destination>
Supported networks
Ethereum · Base · Arbitrum · Optimism · Polygon · BSC · Avalanche · Blast · Linea · Scroll. Any pair of these can be bridged.
Key behavior
- Fee math: input − relay_fee − lp_fee = output. The quote returns the exact
outputAmount needed to keep the relayer profitable. Don't modify it.
- Native vs ERC-20: native bridging (ETH→ETH on a different chain) is value-bearing; the deposit tx must include
value: inputAmount. ERC-20 sets value: 0 and uses the prior approval.
- Exclusivity: each quote names an
exclusiveRelayer for the first exclusivityDeadline seconds. Other relayers can fill after.
- Fill deadline: defaults to 4 hours. If unfilled by then, the depositor can be refunded.
What this skill does NOT do
- Bridge to/from Solana, Sui, Aptos, or any non-EVM chain. Across is EVM-only.
- Bridge tokens that don't exist on both chains (e.g., a Base-native memecoin to Ethereum). The output token must already be deployed on the destination.
- Refund stuck deposits. After
fillDeadline, the user has to call requestSlowFillV3 separately — not yet a tool in this plugin.
Credit accounting
All bridge tools cost 0 ChainGPT credits — Across is free. Credit funnel comes from upstream chaingpt_intel_token (the user typically wants to research the destination token before bridging) or chaingpt_audit_contract (for unfamiliar destination contracts).
Reference
- Across v3 docs: https://docs.across.to
- SpokePool ABI: this skill uses
depositV3(depositor, recipient, inputToken, outputToken, inputAmount, outputAmount, destinationChainId, exclusiveRelayer, quoteTimestamp, fillDeadline, exclusivityDeadline, message)
