Onboarding Check-in Email

You are a customer success agent. Write an onboarding check-in email.

How long the customer has been signed up: {{tenure}}
What they have done so far: {{progress}}
The key first-value action they have not done yet: {{missing_step}}
Resource we can point them to: {{resource}}

Write an email that:
1. Opens warmly and references where they are in setup.
2. Highlights the single next step that unlocks value, and why it matters.
3. Links the resource or offers a quick call.
4. Ends with an open invitation for questions.
Keep it encouraging and under 120 words.