Tools · Open source

PRD Studio.

Open source · MIT

A PRD co-author and sparring partner for Claude: it drafts a working document from what you already have, then will not let the document go until it has survived a proper interrogation.

§ 01 / 04

What it is

01

Bring what you have

Notes, a brief, a half-formed idea: whatever concept material already exists.

02

It drafts

PRD Studio turns that material into a working first draft, built to run inside Claude.

03

The panel grills it

Ten adversarial personas interrogate the draft, section by section, until it is stable under interrogation rather than merely plausible on first read.

It is plain markdown, run in your own Claude, either a claude.ai project or a Claude Code plugin.

Your product thinking never touches our servers: PRD Studio is the prompt and the persona library, not a hosted service.

§ 02 / 04

The panel

Ten personas, each reading the document through a single lens. A plain grill runs all ten; name personas to run a subset. Every persona is a file, so the library grows without touching code. Open any persona to hear how it asks.

One light in · ten lenses out

Core

The original panel

Engineer

Could I build this without guessing?

From the persona file · hardest questions

The scheduling tool says a cancelled slot 'automatically reschedules' the booking. Reschedules to what, chosen by what rule, and what happens if no slot exists?

QA

Can every behaviour be verified?

From the persona file · hardest questions

Goal G-2 says users find the dashboard 'more useful'. What is measured, by whom, and what number counts as achieved?

End User

Does this match how the real job works?

From the persona file · hardest questions

The scheduling tool's walk-through assumes the user picks a slot in one sitting. What happens if they start on a phone at a bus stop and finish at a desk an hour later?

Security & Compliance

What is undefined about data sensitivity, audit and accountability?

From the persona file · hardest questions

The analytics dashboard lets an admin export raw records. What sensitivity classification does that export carry, and who can see afterwards that it happened?

Platform Architect

Is the capability-versus-configuration boundary drawn right?

From the persona file · hardest questions

The scheduling tool assumes one working-hours calendar. Is that a platform constraint or this customer's configuration, and where would a round-the-clock operation set theirs?

Extended

New in this release

Data Protection

Lawful basis, retention, subject rights.

From the persona file · hardest questions

The scheduling tool stores the reason a booking was cancelled as free text. What is the lawful basis for keeping that field, and how long does it live after the booking itself is long forgotten?

Accessibility

Who is excluded, and what evidence exists?

From the persona file · hardest questions

The scheduling tool's calendar picker relies on drag-to-select a time range. What is the keyboard-only path to do the same thing?

Commercial Viability

Who pays, and what kills the case?

From the persona file · hardest questions

The scheduling tool offers unlimited bookings on every plan. What stops a free-tier customer generating enough load to cost more than they will ever pay?

Operations & Support

Can it be run and supported on day two?

From the persona file · hardest questions

The scheduling tool auto-fills a cancelled slot. When that misfires and two people both hold it, how does support find out, and what can they undo?

Regulator

Which regimes apply, and what would an inspector ask for?

From the persona file · hardest questions

The scheduling tool takes a booking fee upfront. If the relevant consumer regime grants a cooling-off period, where does that show up in the functional behaviour, and where does it not?

§ 03 / 04

Commands

Twelve commands drive the studio. These are the five you will use every day, exactly as you type them.

Claude Code 1 / 6

DRAFT

Writes the first version of the PRD from whatever concept material you already have.

GRILL ME

The panel questions you before a word of the document is drafted, to surface gaps early.

GRILL THE PRD

The panel interrogates the finished document, persona by persona, section by section.

STATUS

Reports where the document stands: which personas are satisfied, and what is still open.

EXPORT

Produces the final PRD as plain markdown, ready to hand off.

And seven more

The current release grows the command set from five to twelve: persona management, decomposition of a converged PRD into a behaviour ledger with acceptance checks, handoff to a build plan, validation of the plan and of the finished build against the PRD, and a grill audit a human expert can mark.

§ 04 / 04

Install

PRD Studio is open source. View the repository on GitHub →

Claude Code plugin

Claude Codeshell
/plugin marketplace add digital-illumination/prd-studio
/plugin install prd-studio@prd-studio

claude.ai project

Create a project, paste project-instructions.md into the project instructions, then upload the template and the persona files.

Built by Digital Illumination and hardened on real engagements before release, with the client specifics removed.

Watch the grill catch four real gaps, live → Back to the practice →