Vaccination and health: not required.

No visa is required. May stay in Costa Rica up to 30 calendar days, extendable up to a total of ninety (90) calendar days, according to the applicable legislation. 

Documentation to be submitted:

1. Ticket of continuity of travel or return to the country of origin.
2. Proof of economic solvency, which corresponds to US$100.00 for each month of tourism.
3. Passport in good condition and valid for at least three (3) months.

More details, here.

More information, here.