diff --git a/src/pages/docs/platform/errors/codes.mdx b/src/pages/docs/platform/errors/codes.mdx
index 558f6e095c..af56f22b37 100644
--- a/src/pages/docs/platform/errors/codes.mdx
+++ b/src/pages/docs/platform/errors/codes.mdx
@@ -154,6 +154,14 @@ Examples of this error include attempting to use [channel objects](/docs/liveobj
 Resolution: The following steps can help resolve this issue:
 * Upgrade the Ably SDK to a version that supports the requested operation.
 
+## 40025: Unsupported SDK API <a id="40025"/>
+
+This error occurs when an SDK method is called using an API shape that is no longer supported.
+
+An example of this error is calling an ably-js v2 method using the v1 Node-style callback signature. The v2 SDK is Promise-based and no longer accepts a trailing callback argument. See the [ably-js v2 migration guide](https://github.com/ably/ably-js/blob/main/docs/migration-guides/v2/lib.md) for details on migrating from v1 callbacks to Promises.
+
+Resolution: Update the call site to use the supported API for your SDK and version.
+
 ## 40030: Invalid publish request (unspecified) <a id="40030"/>
 
 This error occurs when a [publish request](/docs/pub-sub#publish) is malformed.