The fields and logic discussed in this guide pertain to the JSON response object from the /v2/tx/status endpoint of the Skip Go API. Refer to the API Reference for detailed schema information.

Understanding the status of a cross-chain transaction and its individual steps is crucial for building a clear and reliable user experience. This guide explains how to interpret the relevant fields from the /v2/tx/status API response to determine if a transaction (and each of its constituent transfers) is pending, successful, has encountered an error, or has been abandoned.

This approach is useful for driving UI elements such as progress indicators, status messages, and error displays in your application.

Example /v2/tx/status Response

Below is an example of a JSON response from the /v2/tx/status endpoint, illustrating some of the key fields discussed in this guide:

{
  "state": "STATE_COMPLETED_SUCCESS",
  "transfer_sequence": [
    {
      "cctp_transfer": {
        "from_chain_id": "42161",
        "to_chain_id": "8453",
        "state": "CCTP_TRANSFER_RECEIVED",
        "txs": {
          "send_tx": {
            "chain_id": "42161",
            "tx_hash": "0xYOUR_SEND_TRANSACTION_HASH_HERE_...",
            "explorer_link": "https://arbiscan.io/tx/0xYOUR_SEND_TRANSACTION_HASH_HERE_..."
          },
          "receive_tx": {
            "chain_id": "8453",
            "tx_hash": "0xYOUR_RECEIVE_TRANSACTION_HASH_HERE_...",
            "explorer_link": "https://basescan.org/tx/0xYOUR_RECEIVE_TRANSACTION_HASH_HERE_..."
          }
        },
        "src_chain_id": "42161",
        "dst_chain_id": "8453"
      }
    }
  ],
  "next_blocking_transfer": null,
  "transfer_asset_release": {
    "chain_id": "8453",
    "denom": "0x833589fCD6eDb6E08f4c7C32D4f71b54bdA02913",
    "amount": "YOUR_EXAMPLE_AMOUNT",
    "released": true
  },
  "error": null
}

Core Concepts for Status Interpretation

The logic relies on a few key pieces of information typically available in the /v2/tx/status API response object:

  1. The Overall Transaction Status: This provides a high-level view of the entire multi-step operation.

    • Look at the top-level state field in the response.
    • Possible values include:
      • 'STATE_COMPLETED_SUCCESS': The entire transaction finished successfully.
      • 'STATE_COMPLETED_ERROR': The transaction finished, but an error occurred.
      • 'STATE_ABANDONED': The transaction was abandoned (e.g., due to timeout or user action).
    • If the state is not one of these terminal states, it’s generally assumed to be pending or in progress.
  2. The Next Blocking Step (or Failure Point): This indicates which specific transfer in the sequence is currently active, or which one caused a failure or abandonment.

    • Utilize the next_blocking_transfer.transfer_sequence_index field (if next_blocking_transfer exists in the response).
    • This will be an index pointing to an operation within the top-level transfer_sequence array.
  3. Categorizing Each Operation in the Sequence: For each operation within the transfer_sequence array of the response, you can determine its individual status:

    • Loading/Pending:

      • The operation’s index matches the next_blocking_transfer.transfer_sequence_index (if next_blocking_transfer exists).
      • AND the overall transaction is still in progress (i.e., the top-level state is not STATE_COMPLETED_ERROR or STATE_ABANDONED).
    • Error/Failed/Abandoned:

      • The operation’s index matches the next_blocking_transfer.transfer_sequence_index (if next_blocking_transfer exists - it is typically null if the overall state is terminal (e.g., STATE_COMPLETED_SUCCESS, STATE_COMPLETED_ERROR, or STATE_ABANDONED) as the transaction is no longer actively blocked or has finished successfully).
      • AND the overall transaction state (the top-level state field) is STATE_COMPLETED_ERROR or STATE_ABANDONED.
      • Additionally, if the overall transaction state is STATE_COMPLETED_ERROR and this is the last operation in the sequence, it is also considered to be in an error state.
      • Note: If the overall transaction state is STATE_COMPLETED_ERROR, it’s also crucial to inspect the specific error object within each individual transfer step in the transfer_sequence (e.g., step.ibc_transfer.packet_txs.error, step.cctp_transfer.error, etc.). This will help pinpoint the exact leg(s) that encountered issues, as the next_blocking_transfer might be null if the transaction reached a terminal error state rather than getting stuck midway.
    • Success:

      • If the overall transaction state (top-level state field) is STATE_COMPLETED_SUCCESS, then all operations in the sequence are considered successful.
      • If the overall transaction is still in progress, or has failed/been abandoned, any operation before the next_blocking_transfer.transfer_sequence_index (if next_blocking_transfer exists - see note above about it typically being null in terminal states) is assumed to have completed successfully.

Example Implementation Logic (JavaScript)

The following JavaScript snippet demonstrates how these concepts can be translated into code to determine the status of each step.

// Assume 'transfer' is the main transaction object from our API
// and 'totalSteps' is the length of transfer.transfer_sequence

// 1. Determine overall transaction status from the main transaction object
const isTransactionSuccessful = transfer.state === 'STATE_COMPLETED_SUCCESS';
const isTransactionFailed = transfer.state === 'STATE_COMPLETED_ERROR';
const isTransactionAbandoned = transfer.state === 'STATE_ABANDONED';

// 2. Get the index of the step that is currently blocking progress or has failed
const nextBlockingIndex = transfer.next_blocking_transfer?.transfer_sequence_index;

// Then, when we process each 'step' in the 'transfer.transfer_sequence' at a given 'index':
// (This logic would typically be inside a loop, e.g., transfer.transfer_sequence.forEach((step, index) => { ... }))

// 3. Categorize the current step:

// Is this step currently "pending" (loading)?
const isStepPending = index === nextBlockingIndex && 
                      !isTransactionFailed && 
                      !isTransactionAbandoned;

// Is this step in an "error" state (or part of an abandoned flow)?
// 'totalSteps' would be transfer.transfer_sequence.length
const isStepAbandonedOrFailed = (isTransactionAbandoned || isTransactionFailed) && 
                                (index === nextBlockingIndex || (index === totalSteps - 1 && isTransactionFailed));

// If 'isTransactionSuccessful' is true, this step is part of an overall successful transaction.
// If a step isn't 'isStepPending' and isn't 'isStepAbandonedOrFailed', 
// and its 'index < nextBlockingIndex' (for an ongoing or failed tx), it's also implicitly a success.

// These boolean flags (isStepPending, isStepAbandonedOrFailed, isTransactionSuccessful)
// are then used to drive the UI styling for that specific step (e.g., node color, edge animation, icons).
// For example:
// if (isStepAbandonedOrFailed) { /* show error UI */ }
// else if (isStepPending) { /* show loading UI */ }
// else { /* show success UI (either part of overall success, or completed before a pending/error state) */ }

By implementing logic based on these fields and states, you can provide users with accurate and timely feedback on the progress of their cross-chain transactions.

Understanding Asset Release (transfer_asset_release)

The transfer_asset_release object in the /v2/tx/status response provides crucial information about where the user’s assets have ultimately landed or are expected to be claimable, especially in scenarios involving swaps or complex routes.

Key fields include:

  • chain_id: The chain ID where the assets are located.
  • denom: The denomination (asset identifier) of the released assets.
  • amount: The quantity of the released assets.
  • released: A boolean indicating if the assets have been definitively released to the user (e.g., available in their wallet or claimable). If false, it might indicate that assets are still in a contract or awaiting a final step for release.

In the event of a cross-chain swap failure, the transfer_asset_release field is particularly important for determining the location and state of the user’s funds. For a comprehensive understanding of how assets are handled in different failure scenarios (e.g., pre-swap vs. post-swap failures), please refer to our detailed guide on Handling Cross-Chain Failure Cases.