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

# E1213 — Input bytes failed schema validation

> Input bytes failed schema validation

# E1213 — Input bytes failed schema validation

| Property     | Value                     |
| ------------ | ------------------------- |
| **Code**     | `1213`                    |
| **Slug**     | `E1213`                   |
| **Category** | `validation` (Validation) |

## What happened

Input bytes failed schema validation.

## Why it happened

The input payload does not conform to the expected schema (e.g., invalid CBOR structure, wrong field types).

## How to fix

Check encoding and field layout against the target handler's expected schema.

## Receipt example

```json theme={null}
{
  "code": 1213,
  "slug": "E1213",
  "category": "validation",
  "what": "Input bytes failed schema validation",
  "fix": "Check encoding and field layout against the target handler's expected schema.",
  "docs_url": "https://docs.cowboy.inc/errors/E1213"
}
```

***

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