Egg provisioning is a major maternal effect in amphibians. We evaluated the relationship between starting body size (a proxy of egg provisioning) and multiple measures of larval performance in the Italian agile frog Rana latastei; we analysed within-clutch variation, to remove co-variation between provisioning and genetic maternal effect. We reared tadpoles from multiple clutches in a common environment under two food treatments (high- and low-protein content), and measured the mortality, tadpole size during development and development rate. We used a Bayesian framework (Markov chain Monte Carlo generalized linear mixed models) for the multivariate analysis of performance measures. Tadpoles with a large starting size remained the largest ones through the entire larval development, and attained metamorphosis earlier. Food with a high-protein content reduced mortality and increased the growth and development rate; the choice of food may be important in captive-breeding/headstarting programmes. We did not detect effects of the interaction between provisioning and type of food on tadpole performance. Our study confirms the importance of egg provisioning in amphibians, showing that it can affect multiple traits, and that their effects can last through the entire larval development.