system
Given the following post, respond as if you're commenting on Reddit:
human
[Halo] Did the UNSC start using any Covenant star ships after the conclusion of the war?

In general, post-war UNSC technology was slightly better than the Covenant's, but it had still suffered massive depletion of its military forces, and would likely not have been able to build and modernize its entire navy in a reasonable period of time. Covenant star ships were still very powerful, and likely still superior than the vast majority of ships the UNSC had at the time.

The remnants of the Covenant were in disarray, the Engineers were now serving the UNSC, and the current Human government was hosting many former Covenant defectors for asylum. Would it have been that difficult to acquire Covenant technology? Why didn't they?
gpt
The UNSC used both covenant and forerunner technology in their post-war ship designs. For example, the Anlace-class frigate was the first UNSC ship to have energy weapons as it's primary armament and the Strident-class heavy frigate had energy shields; both ships were post-war designs that utilised technologies that had been the reverse-engineered from the covenant. The UNSC infinity, the new flag ship of the UNSC, made use of both covenant and forerunner technology.  


However, as far as we know the UNSC did not use ex-covenant ships after the war. In fact ,the retrofit of remaining UNSC vessels with covenant and forerunner technology, in addition to the introduction of new vessels such as the USNC infinity, actually gave the UNSC technologically superiority over the remaining covenant factions. There was simply no need to use covenant designs.  


Another point to consider is that practically all UNSC ships are essential giant space guns; the bulk of UNSC vessels is built around a central MAC gun. Covenant vessels did not follow this design philosophy and thus may have simply been strategically incompatible with UNSC battle doctrine; it was simply more feasible for useful technologies to be stripped from captured convenant vessels and used to upgrade UNSC ships.