In your email, mention:
- The job title
- The employment type (for example, if it’s a full-time position or if it’s a fixed-term contract)
- The must-have requirements (like knowledge of industry, years of experience)
- The salary range (including additional bonuses if applicable)
- The seniority level (if it’s not clear from the job title)
- The time frame you want to close this hire in (including your preferred start date)
- The next steps (for example, whether you’re expecting a confirmation or whether you’re going to schedule a call/meeting to discuss details)
You could also include a document with the detailed job description that will give the agency recruiters a better understanding of the candidates you’re looking for.
Subject line: New job requisition from [Company_name] / New open role at [Company_name]: [job title]
Dear / Hi [partner’s name],
As discussed, we’d like to hire a new [Job title] for our [department]. We’re looking for a professional with at least  years of relevant work experience with expertise in [X technology] who’ll be able to [build mobile applications from scratch]. This is a [full time] position and the salary range is [$Y – $Z]. Attached you’ll find the detailed job description you can use to advertise the job and source candidates.
Ideally, we’d like to have our new hire onboard on [date]. So, we should have a shortlist of [five] candidates by [date]. Please let me know if this sounds like a reasonable timeframe for the particular position.
Feel free to reach out if you need me to clarify the qualification criteria or the scope of responsibilities. I’m also happy to answer any other questions you may have about the position.
[Your email signature]