AWS pinpoint documentation change
Summary
Made IsoCountryCode field optional for non-country-specific origination identities (like RCS agents) and updated ClientToken validation to allow empty strings (minimum length 0, pattern changed from + to *)
Security assessment
These are API specification updates to support new origination identity types (RCS agents) that don't require country codes. The ClientToken change from required to optional with relaxed validation could have security implications if tokens are used for security purposes, but there's no evidence this addresses a specific security vulnerability. The changes appear to be feature enhancements rather than security fixes.