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

# Update Agent

> Update an existing AI agent

If a field is not provided, it will not be updated. To remove a field, set it to `null`.

### Pre-call webhook fields

You can configure a webhook that runs before an inbound call is created. Include any of the following fields when updating an agent:

* `pre_call_webhook_url` – URL that will receive a `POST` request before the call starts.
* `pre_call_webhook_auth_token` – optional bearer token sent in the `Authorization` header.
* `pre_call_webhook_timeout` – how many seconds to wait for the webhook response (defaults to `5`).
* `pre_call_webhook_enabled` – set to `true` to enable the webhook.

See [Call Flow](/call-flow) for details on when this webhook is triggered during a call.