Right. My point being that nobody can really say that a social contract applies to all tables and, given how it will vary, it's not something that helps show an approach is a breach of the social contract. It might be for some and not for others. I think from the perspective of the rules the DM gets to say what the outcome of every action declaration is. Some might not like this or outsource some of this to the players, but that does little to show the game's support for players establishing fiction outside of their control.
Right.
So from the perspective of the rules, the DM decides what every rules outcome of an action declaration is.
But a social contract might govern who gets to narrate what part of the consequences of that action is, because in D&D the rules themselves are usually silent on who owns the narration in cases where the player character is the focus of the narration or the results.
Consider the attack declaration.
The player declares, "I attack the ogre.", rolls a D20 and adds per the rules his bonuses to hit, resulting in say a "14".
The GM responds, after consulting the rules whether this hits or not, and reports back to the player accordingly.
The rules state that if the attack hits, the player rolls damage and its applied against the ogre's hit point total, and if he does not that he does not roll damage.
But they are pretty silent on how to handle this as a process of play, so...
a) Some tables may never narrate the result. The result is simply a deduction of hit points are not and what it looks like isn't important.
b) Some tables may agree to let the DM narrate the result of the hit or miss in a cinematic fashion - "You swing a mighty blow at the ogre, but he turns it aside with his great oaken club!" or "You plunge your blade deep into the ogre's flesh, tearing a gaping wound in its hip. The ogre staggers, roars in pain but despite the wound..."
c) Some tables may decide however, that since misses or hits primarily involve actions by the player's character, that the player ought to be the one narrating the scene once the player knows the general result. This avoids the DM establishing something about the character that goes against the player's conception of his character.
d) Some tables may use a combination, with either the GM or the player adding narration if they feel they have something that adds to the scene, and ignore narration if no one is inspired and we're trying to get the combat over quickly. Or these tables may let the DM narrate some general physical positioning, and allow the player to add detail and color by saying specifically how their character's respond to the success or miss. This works well with tables that have played with each other enough that they can take cues and understand intuitively where each side draws the lines.
All of that is "goodrightfun" if it works for the table.
What you'll find no table really doing if it is to remain a table for long is allowing players to overrule the game by narrating their own preferred results over what the rules process and the GM have established. For example, you won't find many tables that allow the player to narrate that, as a result of a hit on the ogre, that the ogre sits down and begins to cry, or flees in panic, or begs for mercy. Nor ought the player narrate the result of a non-lethal hit as a decapitation, since the rules haven't created the fictional positioning - "The ogre is now dead." yet, but decapitation tends to imply that it is. The ogre is after all an NPC, and so narration pertaining to the ogre properly belongs to the GM. Anything beyond what the has already confirmed, "You wounded it a bit.", is not proper narration, and a player that breaks the social contract and adds improper narration a lot will soon find that part of the social contract up for debate.
Likewise, any GM that violates the player's prerogative of playing their own character to the extent that he uses cinematic narration about a miss to consistently make a player seem ridiculous - every miss is cinematically an epic fumble, puts words in the mouth of the player's character so that they say stupid and unheroic things in response to missing, or interpreting the miss as the character perform ridiculous actions like attacking the wall by mistake, or stumbling around, is very likely to find he has dissatisfied players, because the player will eventually come to dislike having his character characterized by someone other than himself especially if they feel the characterization is unfair and disrespectful. (Of course, a player may want to be playing a ridiculous clown, but those players with very specific ideas about how they want to play are more than any others the ones who appreciate being allowed to narrate their own outcomes, or at least add on to them.)