> For the complete documentation index, see [llms.txt](https://docs.getblock.io/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.getblock.io/api-reference/solana-sol/getfirstavailableblock-solana.md).

# getFirstAvailableBlock - Solana

Example code for the getFirstAvailableBlock JSON-RPC method. Complete guide on how to use the getFirstAvailableBlock JSON-RPC method in the GetBlock Web3 documentation.

This method returns the lowest confirmed block slot that has not been purged from the node's ledger. It defines the earliest point historical queries can reach on that node.

## Parameters

This method does not accept any parameters.

## Request

{% tabs %}
{% tab title="cURL" %}
{% code overflow="wrap" %}

```bash
curl --location --request POST 'https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/' \
--header 'Content-Type: application/json' \
--data-raw '{
    "jsonrpc": "2.0",
    "method": "getFirstAvailableBlock",
    "params": [],
    "id": "getblock.io"
}'
```

{% endcode %}
{% endtab %}

{% tab title="@solana/web3.js" %}
{% code title="example.js" %}

```javascript
const { Connection } = require('@solana/web3.js');

const connection = new Connection('https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/', 'confirmed');

const firstSlot = await connection.getFirstAvailableBlock();

console.log(firstSlot);
```

{% endcode %}
{% endtab %}

{% tab title="Request" %}
{% code title="example.py" %}

```python
import requests

response = requests.post(
    'https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/',
    headers={'Content-Type': 'application/json'},
    json={
        'jsonrpc': '2.0',
        'method': 'getFirstAvailableBlock',
        'params': [],
        'id': 'getblock.io'
    }
)

print(response.json()['result'])
```

{% endcode %}
{% endtab %}

{% tab title="Rust" %}
{% code title="example.rs" %}

```rust
use reqwest::Client;
use serde_json::{json, Value};

#[tokio::main]
async fn main() -> Result<(), Box<dyn std::error::Error>> {
    let client = Client::new();

    let response = client
        .post("https://shared.eu-central-1.getblock.io/<ACCESS-TOKEN>/")
        .header("Content-Type", "application/json")
        .json(&json!({
            "jsonrpc": "2.0",
            "method": "getFirstAvailableBlock",
            "params": [],
            "id": "getblock.io"
        }))
        .send()
        .await?
        .json::<Value>()
        .await?;

    println!("Result: {}", response["result"]);
    Ok(())
}
```

{% endcode %}
{% endtab %}
{% endtabs %}

## Response

```json
{
    "jsonrpc": "2.0",
    "id": "getblock.io",
    "result": 386201344
}
```

## Response Parameters

| Parameter | Type   | Description                                            |
| --------- | ------ | ------------------------------------------------------ |
| jsonrpc   | string | JSON-RPC protocol version ("2.0")                      |
| id        | string | Request identifier matching the request                |
| result    | number | Lowest confirmed block slot still retained by the node |

## Use Cases

* **History Bounds**: Check whether a target slot is inside the node's retained range
* **Archive Routing**: Route older queries to an archive endpoint when the slot falls below this value
* **Backfill Planning**: Set the floor for a historical ingestion job
* **Error Prevention**: Avoid slot-missing errors by validating range inputs up front

## Error Handling

| Error Code | Message           | Description                                                 |
| ---------- | ----------------- | ----------------------------------------------------------- |
| -32603     | Internal error    | Node failed to read the lowest cleanup slot from blockstore |
| -32005     | Node is unhealthy | The node has fallen behind the cluster tip                  |