This article was short, but very helpful. I’m familiar with the prisoner exchanges and the idea of surrendered soldiers being “paroled”, but had never realised the “make an effort” component of it:
Following centuries-old precedent, the United States and Confederate governments used parole and prisoner exchange early in the Civil War, relying on the honor of the parties involved to comply with any terms.
On January 27th, 1862, in return for parole, Col. Milton J. Ferguson of Wayne County gave a pledge of honor to obtain the release of Lieutenant Colonel George W. Neff of Kentucky within 60 days or to surrender to the jailer in Ohio County.
In the interim, Ferguson could neither return to active service against the United States nor provide any aid or information to its enemies.