If this is the case, the only condition for providing your services in the Czech Republic is to notify the relevant Czech authority. The notification is not necessary if your business is not regulated in the Czech Republic.
There is no all-encompassing EU definition of “temporary” and “occasional” provision of services, so it is to be assessed on a case-by-case basis. The relevant factors to consider are the duration, regularity, frequency and continuity of providing the service in the host state.
In case of uncertainty, it is advisable to consult the Czech Trade Licence Office in the area where you plan to conduct your business activity. Typical examples of cross-border provision of services include construction services (even lasting for several years), IT and consulting services, beauty services, etc.
Entrepreneurs are not allowed to provide cross-border services on a regular basis, for example, one day a week or one week a month. In general, services tied to a particular place (e.g. the operation of a restaurant, a hotel, etc.) cannot be provided cross-border. As a general rule, if you as a company or an entrepreneur become integrated into the economy of the host state with regular customers, you have to establish a business there.