Part of a series but if you want to read it anyway all you need to take away is, Loki has been part of the team for probably 5 years now and is mostly reformed
A great golden castle of light sprouted from Loki's rug. It shimmered as he adjusted the algorithm holding the miniature imitation of Asgard's crown jewel together. He sighed and stepped back to admire his handiwork, then, after a few contemplative moments, allowed the light algorithm to fulfill its purpose. A fleet of tiny ships popped into existence and Loki watched as they attacked the structure. Only a few were able to pull in close before the protective bubble, activated by a theoretical Heimdall, encased the city; and those that did were quickly annihilated.
The simulation was over in a matter of minutes. With a wave of his hand Lok dissipated the palace and began to pace
The complete stagnation of his life frustrated him to no end. It had become apparent to him in the last few months that he was not meant for a life of complacency. Never before had his existence been so dull and easily predictable; for the life of him he could not imagine how anyone could live such a lifestyle comfortably.
He conjured a knife, flipping it agitatedly. Spinning around, twisting the rug underneath him, Loki flung the knife towards one of his bookshelves; where it stuck firmly in the dark hardwood with a solid thunk. "Ugh, this is unbearable! I will wither away here and none shall be any the wiser until they deign to grace me with their presence!"
In response to his outburst, Jarvis, his only reliable sounding board of late, sprang to life. "Sir, may I suggest, as I have in the past, that you allow yourself a looser leash. There is nothing to keep you from doing so..." The AI trailed off, it already knew his answer.
Shaking his head, Loki scowled down at his arm, the culprit of his torment, the tracker. "My leash as you so aptly put it, is not mine to control. I feel as much a hound of S.H.I.E.L.D. as Rogers, Barton, and Romanoff. I, simply, am not the attack dog but the caged one."
Jarvis's next words were more to his liking. "Then you would not be interested in reading the mission briefing Ms. Romanoff has sent regarding her latest assignment." There was a pause as Jarvis waited for him to crack. "Both she and-"
"Ah, she mentioned being assigned to a mission with Steve this morning. They must have made it back. Yes, print the thing out for me, Jarvis. I'll take a look at it as I walk the city for the hundredth time."
Half an hour later, with briefing in hand and hair pulled back; Loki strolled to his cafe of choice. One thing he had learned from his months of inactivity was that Midgardians, when on unawares, are remarkably ignorant to appearances. There was no need for elegant disguises when a plain hat or hooded jacket would accomplish the same effect.
Situating himself in a secluded corner, Loki flipped through the documents over a cup of tea. Much to his annoyance a great deal of the briefing was encoded. Even more frustrating, after taking the time to decipher the lettering; it turned out to be nothing more than different ways to say "classified", followed by a smiley face, obviously Natasha's doing. At the end of the deeply unsatisfying read was a note from Natasha that read: "Sorry! Too secret for you. Call you later" closed off by a final infuriating smiley face.
"Oh, that's rich. How typical." Gathering himself up he swept out of the cafe. Taking his annoyance out on a random customer, freezing the man's coffee with a wave of his fingers. He hurried down the street, lamenting the cheap thrills he had been brought to.
Natasha did call him, early in the dark morning hours.
In the middle of solving a delicate glass puzzle, his phone rang. He grasped the glass sphere tight with one hand to avoid dropping it; with the other he reached for the phone, swiping for speaker. Going back to inspecting the puzzle he spoke, allowing more than a little resentment seep into his voice. "Took you long-" Shaky breathing on the other end of the line cut off his sarcastic greeting. With nothing forthcoming, Loki cautiously continued, caught off guard. "Natasha..?"
He could hear her attempting to compose herself on the other side. Utterly alarmed, Loki found himself unable to speak. Only once before had he heard her cry and that had been merely a clever trick. This, clearly, was not that.
After a minute that seemed to stretch on forever, she spoke, voice still wavering just slightly. "Fury is dead."
Glass crunched as Loki dropped the puzzle from his hand. Shocked, his mind had trouble processing her words. "Wha-what?"