Choose one core outcome
Write down the single most important task your first users should complete. A first version should make that task useful from beginning to end, even if the surrounding feature set is limited.
Separate essentials from assumptions
Some features are required for the main workflow. Others express an idea about what users might want later. Keep those assumptions visible so they do not silently become launch requirements.
Include the unglamorous work
Error handling, empty states, permissions and deployment are part of a working product. Discuss them early so the estimate covers more than polished screenshots.
Agree on a review point
Define what you want to learn after the first release. Feedback should help decide the next milestone. Avoid treating the original feature list as a permanent commitment when real usage points in another direction.

Write the first-version promise
Describe the useful outcome a person can complete in the initial release. For a scheduling product, that might be creating a shift, assigning it and confirming availability. Keep the promise specific enough to test. A list of impressive features is not a substitute for an end-to-end outcome. If the proposed scope contains several unrelated promises, consider which one creates the strongest reason for an initial user to try the product.
Example: define what can wait
A scheduling MVP may need basic team access and clear shift status before it needs advanced forecasting. It may need a reliable way to correct an assignment before it needs a decorative analytics dashboard. Explain why each deferred feature can wait without breaking the core journey. This is different from removing difficult work at random. The first version should remain coherent even when the surrounding feature set is deliberately small.
Include the work behind the screens
Account for permissions, data handling, errors, test environments and launch responsibilities in the scope. A screen count alone does not describe the complete effort. Ask the development team which assumptions could materially change the estimate. Resolve the most consequential ones before committing to a fixed milestone. This helps avoid a situation where the visible interface looks complete while essential operational behavior has never been planned.
Plan the first learning cycle
Choose what to observe after release and how that evidence will influence the next milestone. Interview users about the task they attempted, inspect where they needed help and identify workarounds. Keep new requests visible without immediately treating all of them as commitments. A first version is valuable when it helps the team make better decisions about the product, not simply when it reproduces an early idea with fewer screens.