> ## Documentation Index
> Fetch the complete documentation index at: https://help.parafin.ai/llms.txt
> Use this file to discover all available pages before exploring further.

# Program parameters

> Constrain the generated designs — building size, room mix, parking, open space, budget, and program options.

**Program parameters** constrain which designs Parafin generates. Tighten a parameter to narrow the results, then regenerate. Each section below is one accordion in the panel.

Some parameters may not appear for every brand or plan. Prototype-only brands generate from a fixed set of designs, so the building and filter controls below are hidden for them.

## Building

| Control | What it does                                                                                 |
| ------- | -------------------------------------------------------------------------------------------- |
| Floors  | Sets the allowed range for the number of floors.                                             |
| Height  | Sets the allowed range for building height.                                                  |
| Keys    | Sets the allowed range for the number of guestrooms.                                         |
| Zoning  | Shows the zoning limits applied to the design. Use **Edit Zoning** to review or adjust them. |

## Room Mix

| Control           | What it does                                                       |
| ----------------- | ------------------------------------------------------------------ |
| Room-type sliders | One slider per room type sets that type's target share of the mix. |

## Site Open Space

| Control      | What it does                                                                                                                               |
| ------------ | ------------------------------------------------------------------------------------------------------------------------------------------ |
| Open space % | Minimum share of the site left unbuilt and unpaved. Variants without adequate paved area for the required parking spaces are filtered out. |

## Parking

| Control           | What it does                                         |
| ----------------- | ---------------------------------------------------- |
| Spaces Per Key    | Required parking spaces per guestroom (up to 5).     |
| Additional spaces | Extra parking spaces beyond the per-key requirement. |

## Budget

| Control            | What it does                                                                            |
| ------------------ | --------------------------------------------------------------------------------------- |
| Development Budget | Sets the target all-in development budget. Variants outside the range are filtered out. |

## Program Options

| Control          | What it does                                                                                       |
| ---------------- | -------------------------------------------------------------------------------------------------- |
| Prototypes Only  | Limits results to the brand's standard prototype layouts.                                          |
| Category options | Additional brand-specific options that filter the program; the available categories vary by brand. |

For how parameters shape the results, see [Generating designs](/working-with-projects/generating-designs).