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+## AIDL error handling
+
+Starting in **Android U (14)**, `libmediadrm` (app-side) understands extra error
+details from **AIDL** DRM HALs passed through the binder exception message
+as a json string. The supported fields are:
+* `cdmError` (*int*)
+* `oemError` (*int*)
+* `context` (*int*)
+* `errorMessage` (*str*)
+
+The errors details will be reported to apps through the java interface
+`android.media.MediaDrmThrowable`. Please see the javadoc of `MediaDrmThrowable`
+for detailed definitions of each field above.