What documents are needed to extend a 3-month type-O visa for a spouse accompanying a wife with a work permit in Thailand?

To extend a 3-month Type-O visa for a foreign spouse of a Thai national who holds a work permit, essential documents typically include copies of both spouses' passports, the work permit of the Thai spouse, the application for extension of stay, a recent passport photo, and the marriage certificate. Users have noted successes in different approach like obtaining a longer multiple-entry visa in places like Savannakhet, indicating some variability in requirements.