Error Handling

near-kit converts cryptic RPC JSON errors into typed JavaScript Error classes. You can catch these errors and handle them logically.

The Error Hierarchy

All errors extend NearError. You can check for specific types using instanceof.

import {
  FunctionCallError,
  AccountDoesNotExistError,
  NetworkError,
} from "near-kit"

try {
  await near.call("contract.near", "method", {})
} catch (e) {
  if (e instanceof FunctionCallError) {
    // The contract logic failed
    console.log("Panic:", e.panic)
    console.log("Logs:", e.logs)
  } else if (e instanceof AccountDoesNotExistError) {
    // The account isn't real
    console.log(`Account ${e.accountId} not found`)
  } else if (e instanceof NetworkError) {
    // RPC is down
    if (e.retryable) {
      // You might want to try again
    }
  }
}

Panic Messages

When a contract fails, the most important info is the Panic Message. near-kit extracts this from the deep RPC response and puts it right on error.panic.

Common panics include:

• ERR_NOT_ENOUGH_FUNDS
• ERR_INVALID_ARGUMENT
• Smart contract panicked: ...

Use this string to debug or show user-friendly error messages in your UI.