# What does the VARTA error `invalid_request` mean?

The request body or a parameter is malformed, or missing something the endpoint requires.


**HTTP status:** `400`  ·  **Type:** `invalid_request_error`

## What it means

The request body or a parameter is malformed, or missing something the endpoint requires.

## What causes it

Raised directly by handlers across the API — for example a `POST /v1/calls` body that isn't a JSON object, or is missing `agent_id` or `to` (`backend/app/api/v1/calls.py`), a non-object `context`, or a `POST /v1/trunks` request missing `address` (`backend/app/api/v1/telephony.py`). It is also the fallback code for any unrecognised 400 the platform returns.

## What to do

Check the response's `param` field — it names the offending field — and compare your request body against the endpoint's documented shape.