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

# Error Codes Reference

> Complete reference of ZKScore API error codes

## Overview

Comprehensive list of all error codes returned by the ZKScore API.

## Error Code Format

Error codes follow the pattern: `ZKS-XXX-YYY`

* `XXX`: Category code
* `YYY`: Specific error number

## Common Error Codes

| Code          | Description            | Resolution              |
| ------------- | ---------------------- | ----------------------- |
| `ZKS-001-001` | Identity not found     | Verify ZKS ID exists    |
| `ZKS-001-002` | Identity not activated | Activate identity first |
| `ZKS-002-001` | Invalid API key        | Check API key           |
| `ZKS-002-002` | Rate limit exceeded    | Implement backoff       |
| `ZKS-003-001` | Score not found        | User has no score yet   |
| `ZKS-004-001` | Achievement not found  | Verify achievement ID   |
| `ZKS-005-001` | Network error          | Retry request           |

## Related Documentation

* [Error Handling](/guides/error-handling)
* [Status Codes](/reference/status-codes)