# Cross-Chain Transaction Explorer

> Follow one transaction across chains: source tx, bridge deposit and destination fill on a timeline. Give a transaction hash on an EVM chain or a Solana signature. The explorer decodes the source transaction, detects bridge deposits (Circle CCTP, Across, OP Stack and Arbitrum canonical bridges, Wormhole messages), asks the bridge's own status service where the funds went, looks the destination transaction up on the destination chain, and draws the whole journey as one timeline and graph.

Part of usefulweb.site (https://usefulweb.site/). Results are deterministic calculations from the inputs and the listed assumptions; the API returns exactly what the web page shows.

## Use it
- Human interface: https://crosschaintransactionexplorer.usefulweb.site/ (interactive tool at https://crosschaintransactionexplorer.usefulweb.site/tool)
- JSON API: POST https://crosschaintransactionexplorer.usefulweb.site/api/v1/calculate with a JSON object of inputs (schema: https://crosschaintransactionexplorer.usefulweb.site/api/v1/tool)
- OpenAPI: https://crosschaintransactionexplorer.usefulweb.site/openapi.json
- MCP (Streamable HTTP): https://crosschaintransactionexplorer.usefulweb.site/mcp - tool `cross_chain_transaction_explorer`

## Inputs
- mode (select): What do you have?
- chain (select): Source chain (EVM) - Ignored for Solana signatures, which are detected automatically.
- hash (text): Transaction hash or Solana signature
- logs (textarea): Source receipt logs JSON (offline mode) - The "logs" array of eth_getTransactionReceipt.
- followDestination (boolean): Look up the destination transaction

## Method
- EVM source: the Transaction Decoder tool decodes the transaction (status, block time, finality, call, token transfers); the Bridge Transfer Tracker tool finds bridge deposit events (CCTP v1/v2, Across, OP Stack, Arbitrum) and queries the bridge's status service.
- Solana source: getTransaction (jsonParsed, maxSupportedTransactionVersion 0) on the public mainnet-beta RPC; invoked programs are matched against verified Wormhole and Circle CCTP program ids; token balance changes come from pre/post token balances.
- Wormhole: the source hash is looked up on the Wormholescan operations API, which reports the target chain and the redeem transaction when delivered.
- Destination: when a status service returns a destination transaction (e.g. the Across fillTx or a Wormhole redeem) on a supported EVM chain, it is decoded on that chain with the Transaction Decoder.
- Elapsed time = destination block time − source block time. Pasted logs are decoded offline without any network call (no timestamps).