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

# API Deprecation Policy

> How ChainPatrol versions its API, what counts as a breaking change, and the notice you'll get before anything changes underneath you.

ChainPatrol versions its API by URL, with the version encoded as a major-version
segment in the path — the current version is `/api/v2`. This page explains how
long a version stays supported, what triggers a notice, and how that notice
reaches you.

## Versioning

Every endpoint is served under a versioned path, e.g.
`https://app.chainpatrol.io/api/v2`. A new major version is introduced only
when we need to make breaking changes; the previous major version keeps
running, unchanged, for the length of its deprecation window.

## Breaking vs. non-breaking changes

<CardGroup cols={2}>
  <Card title="Non-breaking" icon="circle-check">
    New fields, new endpoints, and new optional parameters. These ship
    without advance notice — existing integrations are unaffected.
  </Card>

  <Card title="Breaking" icon="triangle-exclamation">
    Removing or renaming a field/endpoint, changing a field's type or
    semantics, tightening validation, or making an optional parameter
    required. These require a deprecation notice.
  </Card>
</CardGroup>

## Deprecation window

Breaking changes require a **minimum of 90 days' advance notice**. The
deprecated version remains fully supported for the entire notice window —
no functionality is removed or degraded before the window ends.

<Note>
  **Security exception:** security-critical fixes may need to ship faster
  than the standard 90-day window. When that happens, we give as much
  advance notice as we can responsibly provide given the severity of the
  issue.
</Note>

## How you'll be notified

We notify you through all of the following channels for every breaking
change:

<Steps>
  <Step title="Email">
    Sent to your organization's designated technical contact.
  </Step>

  <Step title="Public changelog">
    Published to the [ChainPatrol changelog](https://chainpatrol.com/changelog).
  </Step>

  <Step title="HTTP response headers">
    Affected endpoints return `Deprecation` and `Sunset` headers, per
    [RFC 8594](https://www.rfc-editor.org/rfc/rfc8594), for the duration of
    the deprecation window.
  </Step>
</Steps>

Make sure your organization's technical contact is up to date so deprecation
emails reach the right person — see
[Update Current User](/docs/external-api/user-me-update) or
[List User Organizations](/docs/external-api/user-orgs) to review your contact
details.

## Staying ahead of breaking changes

* Check the [changelog](https://chainpatrol.com/changelog) periodically.
* Watch for `Deprecation` and `Sunset` response headers on the endpoints you
  call, and alert on their appearance.
* Keep your organization's technical contact current so you don't miss the
  email notice.