The Mukhtasar Jamiul Ulum book discusses hadiths and among its contents discusses intentions
MEANING OF INTENTION

wrong intention wrong address A practice of worship will not be accepted unless two conditions are met, namely sincerity and ittiba'. Sincerity is related to the practice of the heart, namely intention, while ittiba' is related to one's dzahir practice, whether it is in accordance with the guidance of the Prophet sallallaahu 'alaihi wa sallam in worship or not. In other words, sincere intention is a measure of heart worship and ittiba'ur apostle is a measure of spiritual worship.

Many people, after knowing the truth, know which ones are sunnah and which are bid'ah, they are eager to improve their dzahir practices so that they match the Prophet sallallaahu 'alaihi wa sallam in charity. There is no denying that this is a good practice. But unfortunately we often pay less attention to problems related to the heart, namely intention. So we raise this theme in this edition.

Definition of Intention

An intention (intention) in language means al qashdu (intend) and al iraadah (desire) or in other words qashdul quluub wa iraadatuhu (intention and heart's desire). Whereas the definition of intention in terms is as explained by Shaykh Abdurrahman bin Nashir as Sa'di, he said, "Intention is the intention in doing good deeds to draw closer to Allah, seeking His pleasure and reward." (Bahjah Quluubil Abraar wa Qurratu 'Uyuunil Akhyaar Syarah Jawaami'ul Akhbar p. 5)

Shaykh Shalih bin Abdul Aziz Alu Shaykh explained that there are two kinds of intentions in terms of the scholars:

Intentions related to worship. This is the term that is meant by the fiqh experts in various laws when they say, "The first condition: intention". What they mean is the intention for worship that distinguishes one worship from another. For example, to distinguish prayer from fasting, and distinguish obligatory prayer from sunnah prayer.

Intentions related to whom the worship is addressed to. Intention with this understanding is often termed sincere. (Syarah Al Arba'in An Nawawiyyah fil Ahadith Ash Shahihah an Nabawiyyah –Majmu'atul Ulama'- p.31-32)