WASHINGTON — As hard as it may be for lawmakers and the White House to reach an agreement to raise the federal debt ceiling in the coming weeks, striking a budget bargain is just the beginning of the real work.

When and if bipartisan talks being overseen by Vice President Joseph R. Biden Jr. produce some combination of spending cuts, major program changes and revenue increases, the House and Senate must then assemble those various agreements into legislative form and approve them.

While many members of Congress might like the overall framework of any budget deal, some are sure to balk at the legislative detail required to wring money out of popular programs like farm subsidies, Medicaid and Medicare or to force federal retirees to kick in more of their own money for their pensions.

It is one thing to back a general agreement to cut the budget; it can be another thing entirely to support the specific legislation to do so.