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

# Attach evidence

> Add and retrieve audit-bound file evidence on a supported quality record.

The **Attachments / evidence** panel is available when the `attachments` feature is enabled for your
organization. The current UI supports document versions and deviations.

## Add evidence to a deviation

1. Open the deviation detail page.
2. In **Attachments / evidence**, choose a file no larger than 25 MB.
3. Select **Upload** and confirm that the file appears in the panel.
4. Review the displayed file name, type, size, uploader, timestamp, and SHA-256 digest.

Invariant computes the SHA-256 digest on the server. The attachment record and its add event are
written together, binding the server-computed digest into the tamper-evident audit trail. Adding a new
attachment does not require a reason for change.

## Download and verify evidence

Select **Download** beside an attachment. The download requires an authenticated session in the same
organization. Before serving the file, Invariant recomputes its SHA-256 digest and rejects the
download if the stored bytes differ from the digest bound to the attachment and audit event.

<Note>
  The attachment model accepts CAPA and change-control targets for later UI reuse, but their detail pages
  do not yet expose this upload panel. Do not rely on CAPA or change-control file upload until that UI is
  available.
</Note>

<Note>
  End-user deletion and retention-policy controls are not available in this release. Apply your approved
  retention and evidence-handling procedures outside this workflow where required.
</Note>

See [Deviations](/invariant/reference/deviations) for the surrounding investigation workflow and
[Audit Trail](/invariant/reference/audit-trail) for reviewing covered events and chain integrity.