| 400 | VALIDATION_ERROR | Request payload failed validation |
| 400 | INVALID_PERSONA | Persona id is not a valid UUID |
| 400 | INVALID_STYLE | Style id is not a valid UUID |
| 400 | INVALID_AMOUNT | Credit amount is invalid or negative |
| 400 | MISSING_IMAGE_URL | Missing source image for an image-based thumbnail request |
| 400 | MISSING_TARGET_IMAGE | Missing target image for faceswap |
| 400 | MISSING_FACE_REFERENCE | Missing face reference image for faceswap |
| 400 | CONTENT_POLICY | Request blocked by content policy |
| 400 | CANNOT_DELETE_PROCESSING | Attempted to delete a pikzonality while processing |
| 401 | MISSING_API_KEY | Missing X-Api-Key header |
| 401 | INVALID_API_KEY_FORMAT | API key does not start with pkz_ |
| 401 | INVALID_API_KEY | API key is unknown |
| 401 | API_KEY_INACTIVE | API key is disabled |
| 401 | API_KEY_DELETED | API key was deleted |
| 402 | INSUFFICIENT_CREDITS | Balance is too low for requested operation |
| 403 | API_ACCESS_NOT_ENABLED | Account does not have API access |
| 404 | NOT_FOUND | Requested pikzonality does not exist |
| 404 | API_USER_NOT_FOUND | API user record is missing (API access setup issue) |
| 409 | NAME_RESERVED | Pikzonality name is reserved |
| 409 | NAME_ALREADY_EXISTS | Pikzonality name already in use |
| 499 | CANCELLED | Upstream generation was cancelled |
| 500 | GENERATION_FAILED | Upstream generation/scoring/title failure |
| 500 | CONFIGURATION_ERROR | Missing or invalid service configuration variable |
| 500 | CONFIG_ERROR | FAL webhook configuration is incomplete |
| 500 | INVALID_MODEL | No configured generation model for the requested route/model |
| 500 | INVALID_IMAGE | Image URL/body is invalid or not an accessible image |
| 500 | DOWNLOAD_FAILED | Failed to download an input or generated image |
| 500 | UPLOAD_FAILED | Failed to upload generated output to storage |
| 500 | DELETE_FAILED | Failed to delete generated storage artifacts |
| 500 | OUTPAINT_FAILED | Failed while enlarging image with AI outpainting |
| 500 | TITLE_GENERATION_ERROR | Title generation model failed |
| 500 | PARSE_ERROR | Could not parse title model response |
| 500 | FAL_ERROR | FAL generation/webhook processing failed |
| 503 | SERVICE_UNDER_MAINTENANCE | Service maintenance window is active |
| 504 | GENERATION_TIMEOUT | Thumbnail generation exceeded timeout |
| 504 | SCORING_TIMEOUT | Thumbnail scoring exceeded timeout |
| 504 | TITLE_TIMEOUT | Title generation exceeded timeout |
| 504 | FAL_TIMEOUT | FAL generation request exceeded timeout |
