# start-call (/docs/tx/start-call)

Flips a freshly registered subnet from inactive to active: the subnet
token becomes tradable and alpha emission into the subnet's epochs
begins. It does not enable the subnet's share of TAO emission — that
additionally requires the root-gated emission-enabled flag, which only
root can set. Owner-only, callable once per subnet, and only after the
chain's minimum delay since the subnet was registered — calling too
early fails. Until this is called the subnet earns nothing, so run it
as soon as the delay allows.

| Signer    | Pallet          | Wraps                        |
| --------- | --------------- | ---------------------------- |
| `coldkey` | SubtensorModule | `SubtensorModule.start_call` |

## Parameters [#parameters]

| Parameter | Type    | Required | Description                                       |
| --------- | ------- | -------- | ------------------------------------------------- |
| `netuid`  | integer | yes      | Subnet to activate; the signer must be its owner. |

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

## CLI [#cli]

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

```bash
btcli tx start-call \
  --netuid <int> --dry-run
btcli tx start-call \
  --netuid <int> -w my_coldkey
```

## Python [#python]

```python
import bittensor as sub
from bittensor.wallet import Wallet

wallet = Wallet(name="my_coldkey", hotkey="my_hotkey")
intent = sub.StartCall(netuid=1)

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:

```python
await client.execute_tool("start_call", {...}, wallet)
```