# ONNX012: duplicate-metadata-keys

**Code:** `ONNX012`

**Name:** `duplicate-metadata-keys`

**Severity:** error

**Category:** spec

**Target:** model

**Fixable:** No

## Message

Model has duplicate keys in metadata_props.

## Suggestion

Remove duplicate metadata keys, keeping one entry per key.

## Details

The metadata_props field of a model must not contain duplicate keys.