What it is
It is a database specialized in storing vectors (embeddings) and answering "give me the N most similar to this one". Unlike a traditional database that looks for exact matches, this one searches by similarity.
Why it matters to an agency
It is the piece that makes RAG and semantic search over your client's documents possible.
Example
Storing all the help articles as vectors and, when a question comes in, retrieving the 3 most relevant ones to answer it.