פִּ֭י יְדַבֵּ֣ר חָכְמ֑וֹת וְהָג֖וּת לִבִּ֣י תְבוּנֽוֹת׃
Mi boca hablará sabiduría; Y el pensamiento de mi corazón inteligencia.
Rashi on Psalms
and the thoughts of my heart are understanding The thoughts of my heart are understanding.
Ibn Ezra on Psalms
"My mouth" - to teach all the wisdom hidden from them, which those wise of heart explain by riddles.
Ibn Ezra on Psalms
And "thoughts and insights" - that my heart thought.