The tags are meant to help you describe the fiction. You're on that track! So the player says "I close in on the goblin and smack him with my halberd." He rolls a 7, so the monster gets a counter attack—but the weapon he's using is longer, fictionally the goblin isn't in a place to stab him. So the GM can't just say "the goblin stabs you" because that doesn't follow from the fiction. Instead the GM might say "you stab the goblin sure enough, but the goblin takes advantage of your long swing to get in close on you, closer than you can easily swing your halberd."
Now the player's in a spot, what do they do? (Actually, in this case, I might first turn to another player and ask them what they do about it, but let's ignore that for now and keep with one player.) They'll probably do something about the goblin—if they don't, the goblin stabs them and they take damage. If they do something about the goblin, it'll likely trigger defy danger, but that depends on the exact situation. For example, if the player has a word of recall active maybe they say the word and just disappear. Since that's instantaneous I'd say it doesn't trigger defy danger. On the other hand, maybe the player takes the direct route and says "I plant my foot in the goblin's chest and kick him back so he's right where I can halberd him." That seems fictionally sound—small goblin, human leg, getting kicked back is reasonable—so I'd have the player roll defy danger with Str. Then again, maybe the player goes on the defensive—"I hold my halberd crosswise, like a quarterstaff, and do everything I can to block the goblin's attacks." That sounds like defend to me (defending himself) so that move triggers.
The bottom line is, there's no specific way to handle it. Just keep looking at the fiction and what moves trigger. Defy danger is likely to come up, so keep it in mind, but not always.