Literary agent: Reader, editor, manager, dealmaker, negotiator, therapist
The primary reason for a literary agent is that as a writer, you can focus on the writing. Agents will handle the deals, the contract negotiations, and the general admin that comes with publishing a book. (There is a lot of admin). Agents find opportunities for ways to exploit your rights – whether it’s audio, book to film, or translation rights. Writers also often rely on their agent for guidance on strategy.
Agents act as your advocate.
For all that writing and publishing books is an eccentric business, it’s still a business. Publishers are seeking to protect their own interests. Agents ensure that your copyright is protected and that publishers are treating you fairly.