> ## Documentation Index
> Fetch the complete documentation index at: https://docs.joinbase.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Weight setting

> The validator weight-setting cadence and the on-chain submit path.

The validator does not compute scores. The master computes the final UID weight
vector, and the validator fetches it and submits it on-chain. This page covers
the cadence and the validation the validator applies before every submission.

## The submit loop

The submit loop calls `submit_latest_weights` on a fixed interval through
`run_epoch_loop` (`src/platform_network/cli_app/main.py:825-831`,
`bittensor/validator_loop.py:10-18`). The loop runs the callback, then sleeps
the interval, then repeats (`bittensor/validator_loop.py:13-18`).

## Cadence

| Cadence                   | Default   | Source                                                                           |
| ------------------------- | --------- | -------------------------------------------------------------------------------- |
| Validator submit interval | **360 s** | `config/validator.example.yaml:19`, `src/platform_network/config/settings.py:45` |
| Master epoch interval     | **360 s** | `config/master.example.yaml:14`, `src/platform_network/config/settings.py:28`    |
| Weights freshness ceiling | **720 s** | `config/validator.example.yaml:22`, `src/platform_network/config/settings.py:48` |

The validator submit interval (`weights_interval_seconds`) and the master epoch
interval (`epoch_interval_seconds`) share the same default of 360 seconds. The
supervisor's compute-only weights task also runs on the master's
`epoch_interval_seconds` (`src/platform_network/supervisor/weights.py:89-101`).

## What happens each tick

<Steps>
  <Step title="Fetch the latest vector">
    The validator fetches the master's vector from `GET /v1/weights/latest`
    (`validator/weights_client.py:18-30`).
  </Step>

  <Step title="Validate the payload">
    The runner rejects the payload if any check fails
    (`validator/normal_runner.py:93-107`):

    * the payload `netuid` does not match the configured netuid
    * the payload has expired (`expires_at` is in the past)
    * the payload is stale (older than `weights_freshness_seconds`)
    * the `uids` vector is empty
    * the `weights` vector is empty
    * `uids` and `weights` lengths differ
  </Step>

  <Step title="Submit on-chain">
    If the payload passes, the validator calls `set_weights` with the hotkey
    wallet (`validator/normal_runner.py:84`,
    `bittensor/weight_setter.py:27-44`). The call uses
    `wait_for_inclusion=False` and `wait_for_finalization=False`
    (`bittensor/weight_setter.py:39-40`).
  </Step>

  <Step title="Handle rejection">
    A subtensor rejection is detected and logged, and the tick returns without
    raising (`validator/normal_runner.py:88-90`,
    `bittensor/weight_setter.py:7-18`).
  </Step>
</Steps>

## Freshness ceiling

The freshness check compares `now - computed_at` against
`weights_freshness_seconds`, which defaults to **720 seconds**
(`validator/normal_runner.py:99`, `src/platform_network/config/settings.py:48`).
A vector older than this ceiling is skipped, so the validator never submits a
stale vector even if a fetch succeeds.

## If submission is not configured

If the weights client, weight setter, or netuid is not configured,
`submit_latest_weights` logs a warning and returns without submitting
(`validator/normal_runner.py:64-71`).

## Next steps

<CardGroup cols={2}>
  <Card title="The submitter" icon="paper-plane" href="/validators/submitter">
    The submit-only on-chain process.
  </Card>

  <Card title="Configuration" icon="sliders" href="/validators/configuration">
    Tune the cadence and freshness values.
  </Card>
</CardGroup>