How would you describe the protagonist of "The Snows of Kilimanjaro"? Name three of his most important characteristics and supply examples from the story that support your idea.

Harry, the protagonist of "The Snows of Kilimanjaro," is brutally honest with himself, compassionate and loyal enough to try to protect Helen from his brutal honesty, and a failed writer. 
Dying in Africa from a gangrened leg, Harry doesn't romanticize his life or situation but squarely faces what is: he will die, he's bored with life and death, and he does not love Helen. When she says to him "You're not going to die," he says:

"Don't be silly. I'm dying now. Ask those bastards." He looked over to where the huge, filthy birds [vultures] sat, their naked heads sunk in the hunched feathers.

He thinks of death without denial: 

It came with a rush; not as a rush of water nor of wind; but of a sudden, evil-smelling emptiness and the odd thing was that the hyena slipped lightly along the edge of it.

He admits he's tired of everything:

I'm getting as bored with dying as with everything else, he thought.

He thinks to himself that "he did not love her [Helen] at all," and earlier on he tells Helen this when she asks if he loves her:

"No," said the man. "I don't think so. I never have."

Yet he is compassionate enough to realize he is hurting her, and he wants to spare her, so he says to her:

"I'm crazy as a coot and being as cruel to you as I can be. Don't pay any attention, darling, to what I say. I love you, really. You know I love you. I've never loved any one else the way I love you."
He slipped into the familiar lie he made his bread and butter by.

The final sentence about the "lie" that supported him shows he understands he didn't make it as a writer. Instead, he married a wealthy woman who supported him, lied about loving her, and now is about to die with many of his stories never written:

However you make your living is where your talent lies. He had sold vitality, in one form or another, all his life and when your affections are not too involved you give much better value for the money. He had found that out but he would never write that, now, either. No, he would not write that, although it was well worth writing.

He abandoned his love of writing for comfort and security and now it's too late: he "would not write that."
Harry has been damaged by the war and takes that with him into death.