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SUBMIT A PRSUBMIT AN ISSUElast edit: May 21, 2025

Subtensor Error Codes

This section documents the various types of errors that can arise from Subtensor, the blockchain underlying the Bittensor network.

These errors can surface through different interfaces including the Bittensor CLI (btcli), the Bittensor Python SDK, or extrinsic transaction interfaces such as PolkadotJS.

Subtensor errors can be categorized into three main types:

  1. Subtensor Standard Errors have a well defined error code.
  2. Custom Errors are a little trickier, as they only display a numerical code.
  3. Substrate Errors are inherited by Subtensor from Substrate, the underlying software on top of which it is built.

Error Format​

Most errors from the Bittensor network are returned in the following format:

{
    "code": 1010,
    "message": "Invalid Transaction",
    "data": "Custom error: [Error Code]"
}