# Invalid request

`VALIDATION_ERROR` · HTTP 400

## What it means

A query parameter or path segment did not match what the operation accepts.

## What to do

The `detail` field names each parameter that was wrong and what it accepts. Every parameter's format is listed on the operation's reference page.

```json
{
  "type": "https://fentlig.se/developers/errors/validation-error",
  "title": "Invalid request",
  "status": 400,
  "code": "VALIDATION_ERROR"
}
```