Generate a Product Requirements Document (PRD) for an existing project by analyzing README, documentation, and project structure.

Use Case: Onboarding existing projects to Blueprint Development system.

Prerequisites:

• Blueprint Development initialized (docs/blueprint/ exists)

• Project has some existing documentation (README.md, docs/, etc.)

Steps:

Phase 1: Discovery

1.1 Check Prerequisites

ls docs/blueprint/manifest.json

If not found → suggest running /blueprint:init first.

1.2 Gather Project Documentation

Search for existing documentation:

fd -e md -d 3 . | head -20

Key files to look for:

• README.md

• Primary project description

• docs/

• Documentation directory

• CONTRIBUTING.md

• Contribution guidelines

• ARCHITECTURE.md

• Architecture overview

• package.json / pyproject.toml / Cargo.toml

• Project metadata

1.3 Read Primary Documentation

Read and analyze:

• README.md for project purpose, features, and usage

• Package manifest for dependencies and scripts

• Any existing architecture or design docs

Phase 2: Analysis & Extraction

2.1 Extract Project Context

From documentation, identify:

Aspect Source Questions if Missing

Project name Package manifest, README Ask user

Purpose/Problem README intro "What problem does this project solve?"

Target users README, docs "Who are the primary users?"

Core features README features section "What are the main capabilities?"

Tech stack Dependencies, file extensions Infer from files

2.2 Ask Clarifying Questions

Use AskUserQuestion for unclear items:

question: "What is the primary problem this project solves?" options:

• "[Inferred from docs]: {description}" → confirm inference
• "Let me describe it" → free text input

question: "Who are the target users?" options:

• "Developers" → technical documentation focus
• "End users" → user experience focus
• "Both developers and end users" → balanced approach
• "Other" → custom description

question: "What is the current project phase?" options:

• "Early development / MVP" → focus on core features
• "Active development" → feature expansion
• "Maintenance mode" → stability and bug fixes
• "Planning major changes" → architectural considerations

2.3 Identify Stakeholders

Ask about stakeholders:

question: "Who are the key stakeholders for this project?" options:

• "Solo project (just me)" → simplified RACI
• "Small team (2-5 people)" → team collaboration
• "Larger organization" → formal stakeholder matrix
• "Open source community" → contributor-focused

Phase 3: PRD Generation

3.1 Generate Document ID

Before creating the PRD, generate a unique ID:

Get next PRD ID from manifest

next_prd_id() { local manifest="docs/blueprint/manifest.json" local last=$(jq -r '.id_registry.last_prd // 0' "$manifest" 2>/dev/null || echo "0") local next=$((last + 1)) printf "PRD-%03d" "$next" }

Store the generated ID for use in the document and manifest update.

3.2 Create PRD File

Create the PRD in docs/prds/ :

docs/prds/project-overview.md

3.3 PRD Template

Generate PRD with this structure:

id: {PRD-NNN} created: {YYYY-MM-DD} modified: {YYYY-MM-DD} status: Draft version: "1.0" relates-to: [] github-issues: [] name: blueprint-derive-prd

{Project Name} - Product Requirements Document

Executive Summary

Problem Statement

{Extracted or confirmed problem description}

Proposed Solution

{Project description and approach}

Business Impact

{Value proposition and expected outcomes}

Stakeholders & Personas

Stakeholder Matrix

User Personas

Primary: {Persona Name}

• Description: {who they are}
• Needs: {what they need}
• Pain Points: {current frustrations}
• Goals: {what success looks like}

Functional Requirements

Core Features

{List of main capabilities extracted from docs}

User Stories

{User stories derived from features}

• As a {user type}, I want to {action} so that {benefit}

Non-Functional Requirements

Performance

• {Response time expectations}
• {Throughput requirements}

Security

• {Authentication requirements}
• {Data protection needs}

Accessibility

• {Accessibility standards to follow}

Compatibility

• {Browser/platform/version support}

Technical Considerations

Architecture

{High-level architecture from docs or inferred}

Dependencies

{Key dependencies from package manifest}

Integration Points

{External services, APIs, databases}

Success Metrics

Scope

In Scope

• {Included features and capabilities}

Out of Scope

• {Explicitly excluded items}
• {Future considerations}

Timeline & Phases

Current Phase: {phase name}

{Description of current work focus}

Roadmap

Generated from existing documentation via /blueprint:derive-prd Review and update as project evolves

Phase 4: Validation & Follow-up

4.1 Present Summary

Show the user:

✅ PRD Generated: {Project Name}

ID: {PRD-NNN} Location: docs/prds/project-overview.md

Extracted from:

• {list of source documents}

Key sections:

• Executive Summary: {status}
• Stakeholders: {count} identified
• Functional Requirements: {count} features
• Non-Functional Requirements: {status}

Confidence: {High/Medium/Low}

• {High confidence areas}
• {Areas needing review}

Recommended next steps:

1. Review and refine the generated PRD
2. Run /blueprint:derive-adr to document architecture decisions
3. Run /blueprint:prp-create for specific features
4. Run /blueprint:generate-skills to create project skills

4.2 Suggest Follow-up

Based on what was generated:

• If architecture unclear → suggest /blueprint:derive-adr

• If features identified → suggest /blueprint:prp-create for key features

• If PRD complete → suggest /blueprint:generate-skills

Phase 5: Update Manifest

Update docs/blueprint/manifest.json :

• Add PRD to generated_artifacts

• Update has_prds to true

• Update updated_at timestamp

• Update ID registry: { "id_registry": { "last_prd": {new_number}, "documents": { "{PRD-NNN}": { "path": "docs/prds/{filename}.md", "title": "{Project Name}", "github_issues": [], "created": "{date}" } } } }

Tips:

• Be thorough in reading existing docs - they often contain valuable context

• Ask clarifying questions for ambiguous or missing information

• Infer from code structure when documentation is sparse

• Mark uncertain sections for user review

• Keep PRD focused on "what" and "why", not "how"

4.3 Update task registry

Update the task registry entry in docs/blueprint/manifest.json :

jq --arg now "$(date -u +%Y-%m-%dT%H:%M:%SZ)"
--argjson created "${PRDS_GENERATED:-1}"
'.task_registry["derive-prd"].last_completed_at = $now | .task_registry["derive-prd"].last_result = "success" | .task_registry["derive-prd"].stats.runs_total = ((.task_registry["derive-prd"].stats.runs_total // 0) + 1) | .task_registry["derive-prd"].stats.items_created = $created'
docs/blueprint/manifest.json > tmp.json && mv tmp.json docs/blueprint/manifest.json

4.4 Prompt for GitHub Issue (use AskUserQuestion):

question: "Create a GitHub issue to track this PRD?" options:

• label: "Yes, create issue (Recommended)" description: "Creates issue with title '[PRD-NNN] {Project Name}'"
• label: "No, skip for now" description: "Can link later by editing github-issues in frontmatter"

If yes, create GitHub issue:

gh issue create
--title "[{PRD-NNN}] {Project Name}"
--body "## Product Requirements Document

Document: `docs/prds/{filename}.md` ID: {PRD-NNN}

Summary

{Executive summary from PRD}

Key Features

{List of FR-* features}

name: blueprint-derive-prd

Auto-generated from PRD. See linked document for full requirements."
--label "prd,requirements"

Capture issue number and update:

• PRD frontmatter: add issue number to github-issues

• Manifest: add issue to id_registry.documents[PRD-NNN].github_issues

• Manifest: add mapping to id_registry.github_issues

4.5 Prompt for next action (use AskUserQuestion):

question: "PRD generated. What would you like to do next?" options:

• label: "Document architecture decisions (Recommended)" description: "Run /blueprint:derive-adr to capture technical decisions"
• label: "Generate project skills" description: "Extract skills from PRD for Claude context"
• label: "Create a PRP for a feature" description: "Start implementing a specific feature"
• label: "Review and refine PRD" description: "I want to edit the generated PRD first"
• label: "I'm done for now" description: "Exit - PRD is saved"

Based on selection:

• "Document architecture decisions" → Run /blueprint:derive-adr

• "Generate project skills" → Run /blueprint:generate-skills

• "Create a PRP" → Run /blueprint:prp-create (ask for feature name)

• "Review and refine" → Show PRD file location and key sections needing attention

• "I'm done" → Exit

Error Handling:

• If no README.md → ask user for project description

• If blueprint not initialized → suggest /blueprint:init

• If conflicting information in docs → ask user to clarify