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

# Sensitive fields

> Hide customer data fields from AI agents and from teammates without access.

Some customer data shouldn't reach an AI agent or every teammate: a tax ID, a
card's last digits, a home address. Mark those fields **sensitive** and Boom
hides their values. Nothing is sensitive until you mark it.

A hidden value is **still stored** and keeps working: segments still filter on
it and messages can still use it. What changes is who can **read** it.

| Who reads | What they see |
| - | - |
| AI agents (in conversations, the in-app assistant, MCP tools) | `[redacted]` in place of the value, always |
| Teammates whose role can see sensitive data (Owner, Admin, Developer) | The value |
| Everyone else in your organization | A **Hidden** marker instead of the value |

## What you can mark

* **Contact fields** every person has: email, phone number, first name and last
  name. The external ID can't be hidden, because Boom uses it to match people
  across your systems.
* **People attributes**: any key in your people attribute catalog.
* **Custom object attributes**: any key in a custom object type's catalog. A
  hidden attribute with nested data (an object or a list) is hidden whole.

Marking a contact field doesn't mark an attribute that copies it (an `email`
attribute beside the built-in email). Settings suggests those copies so you can
hide them too.

A new attribute from a sync starts visible, and a sync never changes what
you've hidden.

## Where to mark fields

* **Settings › Sensitive data** in the dashboard. Owners and Admins can change
  it; other roles with access to settings see it read-only.
* The [REST API](/api-reference/overview): `GET` and `POST
  /api/v1/cdp/sensitive-fields`. Up to 100 changes per call, applied all or
  nothing: an unknown field fails the whole call.
* [MCP](/use-mcp): the same tools, `cdp_sensitive_fields_get` and
  `cdp_sensitive_fields_set`. A connected AI tool can only **hide** a field.
  Asking it to make one visible again returns `sensitive_unmark_forbidden`; do
  that in Settings or with the REST API.

```json theme={null}
POST /api/v1/cdp/sensitive-fields
{
  "changes": [
    { "scope": "built_in", "field": "PHONE_NUMBER", "isSensitive": true },
    { "scope": "people", "key": "rfc", "isSensitive": true },
    { "scope": "custom_object", "type": "order", "key": "card_last4", "isSensitive": true }
  ]
}
```

<Note>
  Sensitive data settings are being rolled out by organization. Until they are
  on for yours, marking fields returns `sensitive_data_unavailable`; reading the
  list always works.
</Note>


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