The council of Trent anathematized anyone believing in salvation by grace alone through faith alone in Christ alone.
Which is not to be understood as faith which is alone, as Luther himself and many other Reformers expounded on, but which term is used to exclude works as obtaining justification on the basis of the merit of works (and thus faith in such), just as "in Christ alone" is not to be understood as alone in Deity and actions, excluding the Father and Spirit, but as excluding faith in mortals, such as Mary and "saints," or any institution, which Catholicism fosters confidence in.
Yet there is more than one sense of merit, one being that which is owed due to the moral worth of such, as if a wage, and another which is purely of grace, in which God, as He promises, rewards obedience of believers but which God alone is the author of. For man could not and would not believe on the Lord Jesus or follow Him unless God gave him life, and breath, and all good things he has, (Acts 17:25) and convicted him, (Jn. 16:8) drew him, (Jn. 6:44; 12:32) opened his heart, (Acts 16:14) and granted repentance (Acts 11:18) and gave faith, (Eph. 2:8,9) and then worked in him both to will and to do of His good pleasure the works He commands them to do. (Phil. 2:13; Eph. 2:10)
And which "obedience of faith," by the Spirit, (Romans 8:14; 16:26) are credentials of faith, justifying/vindicating man as being a believer, by grace, and fit to be rewarded (Rev. 3:4; Heb. 10:35) for which God alone is actually worthy of.
However, in the gospel of Rome what is meant "by grace alone" is that by the grace of God man actually becomes good enough to be with God and atone for sins, usually commencing at death.