The cover letter should_.

When writing a cover letter, you should:

introduce yourself

mention the job (or kind of job) you're applying for (or looking for)

show that your skills and experience match the skills and experience needed to do the job

encourage the reader to read your resume

finish with a call to action (for example, asking for an interview or a meeting).

Keep it short. A cover letter is meant to be a summary of your resume, so don't write more than one page.