> ## 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.

# Weights API

> The public weights read on the subnet master: the aggregated, chain-ready weight vector for the subnet.

The master computes and serves the aggregated weight vector for the subnet. This
is a public read used by validators (`app_admin.py:136-157`).

## `GET /v1/weights/latest`

Returns the latest aggregated `MasterWeightsResponse` for the subnet. The master
gathers active-challenge inputs and computes the response over the configured
`netuid` and chain endpoint (`app_admin.py:144-151`).

This is a public read (no `require_admin` dependency, `app_admin.py:136`).

```bash theme={"dark"}
curl -s "$MASTER_URL/v1/weights/latest"
```

**Response** — `MasterWeightsResponse` (`schemas/weights.py:33-42`):

| Field                  | Type             | Notes                                                                                           |
| ---------------------- | ---------------- | ----------------------------------------------------------------------------------------------- |
| `netuid`               | integer          | Subnet id; `100` for BASE (`config/settings.py:12`)                                             |
| `chain_endpoint`       | string           | Chain endpoint used for the computation (`schemas/weights.py:35`)                               |
| `uids`                 | array of integer | UIDs in the weight vector (`schemas/weights.py:36`)                                             |
| `weights`              | array of number  | Weights aligned to `uids` (`schemas/weights.py:37`)                                             |
| `hotkey_weights`       | object           | Map of hotkey to weight (`schemas/weights.py:38`)                                               |
| `computed_at`          | datetime         | When the vector was computed (`schemas/weights.py:39`)                                          |
| `expires_at`           | datetime         | Freshness deadline; must be in the future (`schemas/weights.py:40`, `schemas/weights.py:44-48`) |
| `source_challenges`    | array            | Per-challenge contributions, `ChallengeWeightsResult` (`schemas/weights.py:41`)                 |
| `metagraph_updated_at` | datetime         | When the metagraph snapshot was taken (`schemas/weights.py:42`)                                 |

Each entry in `source_challenges` is a `ChallengeWeightsResult`
(`schemas/weights.py:19-24`):

| Field              | Type           | Notes                                                                  |
| ------------------ | -------------- | ---------------------------------------------------------------------- |
| `slug`             | string         | Challenge slug (`schemas/weights.py:20`)                               |
| `emission_percent` | number         | Challenge emission share (`schemas/weights.py:21`)                     |
| `weights`          | object         | Per-hotkey weights from the challenge (`schemas/weights.py:22`)        |
| `ok`               | boolean        | Whether collection succeeded; default `true` (`schemas/weights.py:23`) |
| `error`            | string or null | Error detail when `ok` is false (`schemas/weights.py:24`)              |

The full field-level schema, including the related `ChallengeWeightsResponse` and
`FinalWeights` models, is on the [Weights schema](/reference/weights-schema) page.

## Error responses

| Status | When                                     | Source                 |
| ------ | ---------------------------------------- | ---------------------- |
| `503`  | The master weight service is unavailable | `app_admin.py:138-142` |
| `502`  | Computation raised an unexpected error   | `app_admin.py:154-157` |

## Freshness

The master weights freshness window is defined by
`MASTER_WEIGHTS_FRESHNESS_SECONDS = 720` (`schemas/weights.py:8`). The
`expires_at` field is validated to be in the future when the response is built
(`schemas/weights.py:44-48`).

## Related

<CardGroup cols={2}>
  <Card title="Weights pipeline" icon="scale-balanced" href="/architecture/weights-pipeline">
    How this vector is computed and normalized each epoch.
  </Card>

  <Card title="Validator network" icon="shield-halved" href="/architecture/validator-network">
    The submit-only process that posts this vector on-chain.
  </Card>

  <Card title="Weights schema" icon="table-list" href="/reference/weights-schema">
    The field-level models behind this response.
  </Card>
</CardGroup>