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

# Error Handling

> Handle errors from @cofhe/sdk operations using typed CofheError objects

All SDK operations return values directly and throw typed `CofheError` objects on failure. This replaces the `Result` wrapper pattern used by `cofhejs`.

## Catching errors

```typescript theme={null}
import { isCofheError, CofheErrorCode, Encryptable } from '@cofhe/sdk';

try {
  const [encrypted] = await client
    .encryptInputs([Encryptable.uint32(42n)])
    .execute();
} catch (err) {
  if (isCofheError(err)) {
    console.error(err.code);    // CofheErrorCode enum value
    console.error(err.message); // human-readable description
  }
}
```

## CofheError structure

Every `CofheError` has:

* `code` — a `CofheErrorCode` enum value identifying the error type
* `message` — a human-readable description of what went wrong

Use `isCofheError(err)` to check if a caught error is a `CofheError`.

## Common error codes

| Error code       | When it occurs                                              |
| ---------------- | ----------------------------------------------------------- |
| `ZkPackFailed`   | `encryptInputs` exceeded the 2048-bit plaintext limit       |
| `PermitNotFound` | No permit found for the given `chainId + account`           |
| `PermitInvalid`  | The permit signature is invalid or expired                  |
| `DecryptFailed`  | Decryption request was rejected by the Threshold Network    |
| `NotConnected`   | Attempted an operation before calling `client.connect(...)` |

## Error handling patterns

### Encryption errors

```typescript theme={null}
import { isCofheError, CofheErrorCode, Encryptable } from '@cofhe/sdk';

try {
  const encrypted = await client
    .encryptInputs([Encryptable.uint128(veryLargeValue)])
    .execute();
} catch (err) {
  if (isCofheError(err) && err.code === CofheErrorCode.ZkPackFailed) {
    console.error('Input too large — split into multiple calls');
  }
}
```

### Decryption errors

```typescript theme={null}
import { isCofheError, CofheErrorCode, FheTypes } from '@cofhe/sdk';

try {
  const plaintext = await client
    .decryptForView(ctHash, FheTypes.Uint32)
    .execute();
} catch (err) {
  if (isCofheError(err) && err.code === CofheErrorCode.PermitNotFound) {
    // Create a permit and retry
    await client.permits.getOrCreateSelfPermit();
    const plaintext = await client
      .decryptForView(ctHash, FheTypes.Uint32)
      .execute();
  }
}
```