register-subnet

Registers a brand-new subnet with the signing coldkey as its owner and the wallet's hotkey as the subnet-owner hotkey. The network registration cost — potentially thousands of TAO — is taken from the coldkey; it doubles after each new subnet registration and decays linearly back over the lock reduction interval, and is only known at execution time, so a configured spend cap blocks this call until raised. The full cost becomes the new subnet's initial TAO pool reserve — a sunk cost, not a refundable deposit. Network registrations are rate-limited per coldkey. If the chain is at its subnet limit, registering dissolves the non-immune subnet with the lowest EMA price to free the slot (the new subnet reuses its netuid). The new subnet starts inactive: call start_call once the chain's activation delay has passed to activate it; the subnet's share of TAO emission additionally stays off until root enables the subnet's emission-enabled flag. This is a major, expensive commitment — check the current cost before sending.

Parameters

Address parameters (--hotkey, --coldkey, --dest, ...) accept a raw ss58 address, an address-book or proxy-book name, or a local wallet/hotkey name.

CLI

Preview with --dry-run (shows fee, effects, and policy result without submitting), then submit:

btcli tx register-subnet --dry-run
btcli tx register-subnet -w my_coldkey

Python

import bittensor as sub
from bittensor.wallet import Wallet

wallet = Wallet(name="my_coldkey", hotkey="my_hotkey")
intent = sub.RegisterSubnet()

async with sub.Client("finney") as client:
    plan = await client.plan(intent, wallet)   # fee, effects, policy — no submission
    result = await client.execute(intent, wallet)
    if not result.success:
        print(result.error.code, result.error.remediation)

Or build it by op name, as an agent would:

await client.execute_tool("register_subnet", {...}, wallet)