/evm-atlas

Across Bridging

Overview

Use Across as a read-only source for Across Protocol intent-based deposit/fill status, matching an origin deposit transaction to its destination fill transaction, and enumerating recent deposits for a route.

Default to the public API base URL:

https://app.across.to/api

No API key is required or documented for these read endpoints.

Never execute bridge steps from this skill. Do not sign messages, submit deposit transactions, or call any Across SpokePool write method (depositV3, fillV3Relay, speedUpV3Deposit, etc.). Returned deposit and fill data are for inspection only.

Across is an intents/relayer bridge, not a lock-and-mint bridge: a depositor locks funds into an origin-chain SpokePool, and an off-chain relayer immediately fronts the equivalent output on the destination-chain SpokePool from its own inventory, later reimbursed through Across's UMA-secured bundle settlement. There is no destination mint event to look for; the report-relevant destination event is a relayer-funded fill, not a mint.

Read-Only Router

Use this router after the known origin and destination chains are confirmed against references/generated/target-mainnets.json.

1. Known origin deposit tx hash: call GET /deposit/status?depositTxHash=<hash>&originChainId=<id>. This is the most useful lookup — connects a known origin-chain deposit transaction to its relayer fill.
2. Known origin chain + deposit ID: call GET /deposit/status?originChainId=<id>&depositId=<id> when the numeric SpokePool deposit ID is known instead of a tx hash (e.g. decoded from a V3FundsDeposited log).
3. Browse recent/matching deposits: call GET /deposits with optional filters (originChainId, destinationChainId, depositor, recipient, status, limit) to find a deposit when only a wallet or route is known, not an exact tx hash or deposit ID.
4. Supported routes: call GET /available-routes to check which origin/destination chain and token pairs Across currently supports; optionally filter with originChainId, destinationChainId, originToken, destinationToken.

Example status lookup by deposit tx hash:

curl -sS "https://app.across.to/api/deposit/status?depositTxHash=0xTX_HASH&originChainId=1"

Example status lookup by origin chain + deposit ID:

curl -sS "https://app.across.to/api/deposit/status?originChainId=1&depositId=4181942"

Example deposit browse:

curl -sS "https://app.across.to/api/deposits?originChainId=1&destinationChainId=8453&limit=5"

GET /deposit/status requires either depositTxHash or (originChainId + depositId); calling it with no identifying params returns a 400 IncorrectQueryParamsException, and an unmatched deposit returns a 404 DepositNotFoundException.

Request Fields

Do not invent wallet addresses. Use only user-provided or known on-chain addresses.

Report Fields

Extract and report these fields when present (from /deposit/status or a /deposits row — both share the same schema):

inputAmount and outputAmount are raw integer units in the respective token's smallest denomination. Convert with token decimals when present. USD fee fields (bridgeFeeUsd, fillGasFeeUsd) are already decimal.

SpokePool Contracts and Events

Across routes deposits and fills through per-chain SpokePool contracts rather than a single hub contract. The Ethereum mainnet SpokePool is at 0x5c7BCd6E7De5423a257D81B442095A1a6ced35C5 (an EIP-1967 proxy; current implementation labeled Ethereum_SpokePool on block explorers). Resolve SpokePool addresses on other target chains from references/generated/target-mainnets.json or the chain's block explorer rather than hardcoding a full table here.

When decoding logs directly instead of using the API, the relevant SpokePool events are:

Both the current and deprecated event names are present in the deployed SpokePool ABI; a specific deposit emits only one of the pair depending on the protocol version active at that block. Match an origin deposit to its destination fill by the shared depositId (and originChainId), not by matching transaction hashes across chains.

Status Values

Interpret the status field as:

For filled or slowFilled, still verify the destination fill transaction directly with explorer or RPC data when the destination chain is a target chain.

Failure Handling

• 400 IncorrectQueryParamsException from /deposit/status: supply either depositTxHash or both originChainId and depositId.
• 404 DepositNotFoundException: report that Across has no record for those params and continue normal explorer/RPC analysis; do not assume the deposit never happened, since /deposit/status only indexes deposits made through Across's own SpokePool flow.
• /deposits returning an empty array: broaden or drop filters, or fall back to a direct depositTxHash lookup.
• status: "expired" or "refunded": report as a failed/refunded transfer; verify the refund transaction on the origin chain when a target chain.
• Rate limiting or 5xx responses: back off and continue explorer/RPC analysis.

Sources

• https://docs.across.to/reference/api-reference
• https://docs.across.to/introduction/what-is-across
• https://docs.across.to/concepts/intents
• https://github.com/across-protocol/contracts