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Documentation Index

Fetch the complete documentation index at: https://doc.getrationale.app/llms.txt

Use this file to discover all available pages before exploring further.

The Designs first. Docs follow. workflow lets you go from pixels to requirements without writing a single line of spec manually. Paste a Figma file URL, and Rationale reads every frame, downloads the screen images, and produces a structured PRD. The result lands in your project and can immediately be used as the spec for a Match audit.

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When to use this workflow

Use this workflow when:
  • You have designs but the requirements were never written down.
  • You’re inheriting an existing product and need to document how it works.
  • Your team designs before speccing and wants the PRD as a by-product, not a prerequisite.
If you already have a PRD and want to audit your designs against it, use Watch for design drift with Rationale Match instead.

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How to generate a PRD from designs

1

Create a new project

Open Rationale and click New project. On the gateway picker, select Designs first. Docs follow.
2

Name your project

Enter a name for the surface you’re documenting, for example “Onboarding flow”.
3

Paste your Figma URL

Paste a Figma file or frame URL (for example https://figma.com/file/…). You can paste a top-level file URL to capture all frames, or a specific frame URL to scope the PRD to a subset of screens.
4

Click Generate PRD

Click Generate PRD. Rationale begins processing immediately and shows you live progress.
5

Watch the generation steps

Rationale works through four steps in sequence:
  1. Reading your Figma file — fetches the file structure and frame metadata
  2. Downloading screen images — captures a rendered image of each frame
  3. Writing your PRD — analyses every screen and produces the requirements document
  4. Saving your PRD — persists the result to your project
Once all steps complete, Rationale takes you directly to the project.
6

Review the generated PRD

Your project opens on the Summary tab. The generated PRD is attached as the spec for this version. Review it, edit any sections that need adjustment, and use it as the source of truth going forward.

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After generation

Once the PRD is saved to your project, you can:
  • Use it as the spec for a Match project. The generated PRD can serve as the baseline for ongoing drift detection. Create a new Match project and reference the same Figma file to start watching for changes against the spec Rationale just wrote.
  • Export or share the PRD. Open the Summary tab to review coverage, entry points, core flows, and business rules derived from your designs.
If your Figma file has many frames, scope the URL to a specific page or frame to keep the PRD focused. A tighter scope produces more precise requirements.
Rationale reads the frames visible in the Figma file at generation time. If you add screens later, run the workflow again or connect the file to a Match project so future saves re-audit the updated designs.