# Extension contacts

- [Favorite](/development-portsip/rest-apis/version-22.1/api-reference/user/extension-contacts/favorite.md)
- [Unfavorite](/development-portsip/rest-apis/version-22.1/api-reference/user/extension-contacts/unfavorite.md)
- [Sync tokens](/development-portsip/rest-apis/version-22.1/api-reference/user/extension-contacts/sync-tokens.md)
- [Diff](/development-portsip/rest-apis/version-22.1/api-reference/user/extension-contacts/sync-tokens/diff.md)