Typical continuo instruments used in french baroque music are "basses de violon" (a cello-like, large scaled instrument often replaced by the cello in modern performances), organ, harpsichord, theorbo, bass viol and bassoon or "basse de cromorne" (a kind of bass oboe).
Since the instrumental ensemble is mostly constricted to 4 parts only (wind instruments and violins playing the same line), it is very easy to reduce the instrumentation if needed.