---
title: CelFilterValidation
description: CelFilterValidation describes the validation configuration returned to
source_url:
  html: https://thru.org/docs/api-ref/grpc/messages/thru/common/v1/cel-filter-validation/
  md: https://thru.org/docs/api-ref/grpc/messages/thru/common/v1/cel-filter-validation.md
---

# CelFilterValidation

CelFilterValidation describes the validation configuration returned to clients to help them build safe filter expressions.

**Package:** `thru.common.v1`

## Fields

| Field | Type | # | Description |
| - | - | - | - |
| `allowed_functions` | repeated `string` | 1 · optional | List of allowed CEL function names for a specific request type. |
| `allowed_fields` | repeated `string` | 2 · optional | List of allowed field names accessible to the CEL expression. |
| `max_complexity` | `uint32` | 3 · optional | Maximum AST node count permitted for a CEL expression. |