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

# Load Index

Loads and returns an existing `EncryptedIndex` instance.

```python theme={null}
client.load_index(
    index_name,
    index_key = None,
)
```

### Parameters

| Parameter    | Type    | Description                                                                                                                                       |
| ------------ | ------- | ------------------------------------------------------------------------------------------------------------------------------------------------- |
| `index_name` | `str`   | Name of an existing index                                                                                                                         |
| `index_key`  | `bytes` | *(Optional)* 32-byte encryption key. Required for indexes created with the SDK-supplied KEK path (`provider: none`); omit for KMS-backed indexes. |

<Note>In v0.17 `index_key` is optional. KMS-backed indexes (created with `kms_name`) omit it — the server resolves the DEK via the persisted `KMSBlob`. SDK-supplied indexes (created with only `index_key`) must re-supply the same 32-byte key here.</Note>

<Warning>
  For SDK-supplied indexes, the encryption key must exactly match the key used during index creation. KMS-backed indexes are tied to their `kms_name` slot in the service YAML — load fails if that slot is missing or unreachable.
</Warning>

### Returns

An instance of `EncryptedIndex` bound to the loaded index. The SDK probes the describe endpoint during load, so a missing or inaccessible index raises here rather than silently returning a phantom handle.

### Exceptions

<AccordionGroup>
  <Accordion title="ValueError">
    * Raised if `index_key` is provided but is not exactly 32 bytes.
    * Raised if the index does not exist on the server (the describe probe fails).
    * Raised if the supplied key does not match the cached envelope hash (SDK-supplied path).
    * Raised by the server if a KMS-backed index's slot is unavailable.
  </Accordion>

  <Accordion title="Network/API Errors">
    * Raised if the API request fails due to network issues.
    * Raised if the server returns an HTTP error status.
    * Raised if the server is unreachable or times out.
  </Accordion>
</AccordionGroup>

### Example Usage

#### SDK-supplied index

```python theme={null}
from cyborgdb import Client

client = Client(base_url='http://localhost:8000', api_key='your-api-key')

# Same 32-byte key used during create_index()
index_key = your_existing_32_byte_key

index = client.load_index("my_index", index_key)
```

#### KMS-backed index

```python theme={null}
# No key required — the server resolves the DEK via the index's KMSBlob.
index = client.load_index("kms_index")
```