> ## Documentation Index
> Fetch the complete documentation index at: https://fhenix-ci-version-drift-check.mintlify.site/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
  }
}
```

## What a CofheError carries

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       |
| `ConsumingContractUninitialized` | `execute()` was called without `setConsumingContract(...)`  |
| `ACPNotFound`                    | No ACP found for the given `chainId + account`              |
| `ACPInvalid`                     | The ACP signature is invalid                                |
| `ACPExpired`                     | The ACP is past its expiration                              |
| `ACPRevoked`                     | The issuer revoked this ACP                                 |
| `ACPDenied`                      | The ACP does not cover the requested handle                 |
| `ACPRequired`                    | The flow needs an ACP and none was supplied                 |
| `DecryptFailed`                  | Decryption request was rejected by the Threshold Network    |
| `NotConnected`                   | Attempted an operation before calling `client.connect(...)` |

<Note>
  The `Permit*` codes are gone. `PermitNotFound` and `PermitInvalid` are now `ACPNotFound` and `ACPInvalid`. The set also expanded: expiry, revocation, and scope denial each have their own code, so you no longer have to infer which one applied from the message.
</Note>

## Error handling patterns

### Encryption errors

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

try {
  const encrypted = await client
    .encryptInputs([Encryptable.uint128(veryLargeValue)])
    .setConsumingContract(contractAddress)
    .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.ACPNotFound) {
    // Create an ACP and retry
    await client.acp.getOrCreateSelfACP();
    const plaintext = await client
      .decryptForView(ctHash, FheTypes.Uint32)
      .execute();
  }
}
```

### Distinguishing why an ACP is invalid

The decrypt flows call `ACPUtils.validate(acp)` internally before talking to the Threshold Network. That helper enforces **schema + signed + not-expired** all at once, so when it fails the recovery path depends on **which** check tripped.

Use the non-throwing `ValidationUtils.isValid` helper from `@cofhe/sdk/acps` to pre-flight the active ACP and route based on the typed reason, which avoids the thrown error path entirely:

```typescript theme={null}
import { FheTypes } from '@cofhe/sdk';
import { ValidationUtils } from '@cofhe/sdk/acps';

const active = client.acp.getActiveACP();
const result = active
  ? ValidationUtils.isValid(active)
  : { valid: false, error: 'not-signed' as const };

if (!result.valid) {
  switch (result.error) {
    case 'expired':
      await client.acp.getOrCreateSelfACP(); // create a fresh one
      break;
    case 'not-signed':
      await client.acp.getOrCreateSelfACP(); // prompt the wallet to sign
      break;
    case 'invalid-schema':
      client.acp.removeActiveACP(); // stored payload is malformed
      break;
  }
}

const plaintext = await client
  .decryptForView(ctHash, FheTypes.Uint32)
  .execute();
```

`ValidationResult.error` is the typed union `'invalid-schema' | 'expired' | 'not-signed' | null`. See [validating ACPs](/client-sdk/guides/acps#validating) for the full helper surface.

<Note>
  If you prefer the throwing path: `ACPUtils.validate(acp)` raises plain `Error`s with messages `ACP is expired` / `ACP is not signed` (or a Zod schema error). These are not wrapped in `CofheError`, so use `err.message` rather than an error code to branch.
</Note>