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

# Rust — Error Handling

## Error Handling

All SDK methods return `polynode::Result<T>`, which wraps `polynode::Error`:

```rust,no_run theme={null}
use polynode::{PolyNodeClient, Error};

# async fn example() -> polynode::Result<()> {
let client = PolyNodeClient::new("pn_live_YOUR_KEY")?;

match client.market("invalid-token-id").await {
    Ok(market) => println!("{:?}", market),
    Err(Error::NotFound(msg)) => println!("not found: {}", msg),
    Err(Error::Auth(msg)) => println!("auth failed: {}", msg),
    Err(Error::RateLimited(msg)) => println!("rate limited: {}", msg),
    Err(Error::Api { status, message }) => println!("API error {}: {}", status, message),
    Err(Error::Http(e)) => println!("network error: {}", e),
    Err(Error::Disconnected) => println!("WebSocket disconnected"),
    Err(e) => println!("other: {}", e),
}
# Ok(())
# }
```

### Error Variants

| Variant                   | When it occurs                                       |
| ------------------------- | ---------------------------------------------------- |
| `Http`                    | Network-level request failure                        |
| `WebSocket`               | WebSocket connection or protocol error               |
| `Json`                    | Response deserialization failure                     |
| `Api { status, message }` | Server returned a non-success status                 |
| `Auth`                    | 401 or 403 from the API                              |
| `RateLimited`             | 429 from the API                                     |
| `NotFound`                | 404 from the API                                     |
| `Disconnected`            | WebSocket connection lost                            |
| `Decompression`           | zlib decompression failure                           |
| `ConnectionClosed`        | Server closed the WebSocket                          |
| `Url`                     | URL parse error                                      |
| `Trading`                 | Trading-specific error (feature: `trading`)          |
| `Signing`                 | EIP-712 signing failure (feature: `trading`)         |
| `Sqlite`                  | Local database error (feature: `cache` or `trading`) |
| `Io`                      | File I/O error (feature: `cache` or `trading`)       |
| `Cache`                   | Cache-specific error (feature: `cache`)              |