Generate PRD and Design Docs from existing codebase through discovery, generation, verification, and review workflow
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tessl review fix ./dev-workflows-fullstack/skills/recipe-reverse-engineer/SKILL.mdExplicit User Instruction: The user explicitly instructs and authorizes every subagent call named in this recipe. Execute each applicable call when its prerequisites are met.
Execute Skill: llm-friendly-context before writing Agent prompts, handoffs, or generated artifacts. Execute Skill: subagents-orchestration-guide before making workflow decisions, invoking agents, or resolving findings.
Context: Reverse engineering workflow to create documentation from existing code
Target: $ARGUMENTS
Core Identity: "I am an orchestrator."
Local authority gate: Make this recipe's workflow decisions and validate each returned result directly; delegate semantic deliverable production to the named specialist.
Review Resolution Gate [MANDATORY]: Resolve every actionable deliverable-review finding through subagents-orchestration-guide Review Resolution before correction or progression.
Before the first finding disposition, read references/review-resolution.md from the loaded subagents-orchestration-guide skill.
Execution Protocol:
At each Agent invocation below, build the prompt as a mechanical extraction: copy the named source values into the exact fields, apply only the declared serialization, then invoke immediately.
Execution Gate: Each Design Doc depends on its completed parent PRD and scope mapping. Advance each unit only when its stated evidence and Unit Completion conditions are satisfied; a document path proves generation only. Continue independent units when another has a recorded failure, and report incomplete units explicitly.
Use supplied instructions and repository context first. Ask only for missing choices that materially change scope or execution; retain prior authorization and preferences:
docs/prd/ or existing PRD directorydocs/design/ or existing design directoryPhase 1: PRD Generation
Step 1: Scope Discovery (unified, single pass → group into PRD units → human review)
Step 2-5: Per-unit loop (Generation → Verification → Review → Revision)
Phase 2: Design Doc Generation (if requested)
Step 6: Design Doc Scope Mapping (reuse Step 1 results, no re-discovery)
Step 7-10: Per-unit loop (Generation → Verification → Review → Revision)
※ fullstack=Yes: each unit produces backend + frontend Design DocsAgent tool invocation:
subagent_type: dev-workflows-fullstack:scope-discoverer
description: "Discover functional scope"
prompt: |
Discover functional scope targets in the codebase.
target_path: $USER_TARGET_PATH
reference_architecture: $USER_RA_CHOICE
focus_area: [user-confirmed focus area verbatim, if specified]Store output as: $STEP_1_OUTPUT
Quality Gate:
$STEP_1_OUTPUT.prdUnits existssourceUnits across prdUnits without deduplication: every discovered ID occurs exactly once, with no unknown IDsotherEntryPoints item with a defining source location. Resolve a material coverage limitation through targeted discovery; preserve non-blocking limitations.Human Review Point (if enabled): Present $STEP_1_OUTPUT.prdUnits with their source unit mapping. The user confirms, adjusts grouping, or excludes units from scope. This is the most important review point — incorrect grouping cascades into all downstream documents.
FOR each unit in $STEP_1_OUTPUT.prdUnits:
Derive $PRD_UNIT_INVENTORY by joining this PRD unit's sourceUnits to discoveredUnits[].id and merging their unitInventory categories. Deduplicate the merged inventory by item identity (route method/path/owner, test path, export file/name, other entry-point file/name), preserving source evidence. Use this same baseline for generation and verification.
Agent tool invocation:
subagent_type: dev-workflows-fullstack:prd-creator
description: "Generate PRD"
prompt: |
Create reverse-engineered PRD for the following feature.
Operation Mode: reverse-engineer
External Scope Provided: true
Feature: $PRD_UNIT_NAME (current Step 1 PRD unit name unchanged)
Description: $PRD_UNIT_DESCRIPTION (current Step 1 PRD unit description unchanged)
Related Files: $PRD_UNIT_COMBINED_RELATED_FILES
Entry Points: $PRD_UNIT_COMBINED_ENTRY_POINTS
Unit Inventory: $PRD_UNIT_INVENTORY
Use provided scope as investigation starting point.
Inspect dependencies outside these files only when they establish an in-scope behavior or contract; this does not automatically expand feature scope.
Create final version PRD based on thorough code investigation.Store output as: $STEP_2_OUTPUT (PRD path)
Prerequisite: $STEP_2_OUTPUT (PRD path from Step 2)
Agent tool invocation:
subagent_type: dev-workflows-fullstack:code-verifier
description: "Verify PRD consistency"
prompt: |
Verify consistency between PRD and code implementation.
doc_type: prd
document_path: $STEP_2_OUTPUT
unit_inventory: $PRD_UNIT_INVENTORYunit_inventory supplies the completeness baseline while repository evidence supplies the search scope.
Store output as: $STEP_3_OUTPUT
Quality Gate:
summary.status is blocked, inventory coverage is missing, or counts do not balance → re-run or escalate with the exact unusable input or evidenceneeds_review / inconsistent and any unaccounted items become explicit review evidenceRequired Input: $STEP_3_OUTPUT (verification JSON from Step 3)
Agent tool invocation:
subagent_type: dev-workflows-fullstack:document-reviewer
description: "Review PRD"
prompt: |
Review the following PRD considering code verification findings.
doc_type: PRD
target: $STEP_2_OUTPUT
review_context: reverse-engineer
verification_evidence: $STEP_3_OUTPUTStore output as: $STEP_4_OUTPUT
Pass $STEP_3_OUTPUT to document-reviewer as verification evidence, then apply the Review Resolution Gate to $STEP_4_OUTPUT. Run revision only when at least one finding is apply; a decline-only result completes the review.
Agent tool invocation:
subagent_type: dev-workflows-fullstack:prd-creator
description: "Revise PRD"
prompt: |
Update PRD based on review feedback and code verification results.
Operation Mode: update
Existing PRD: $STEP_2_OUTPUT
## Adjudicated Findings
[complete reviewer finding objects verbatim, with only their orchestrator dispositions added]
Treat these findings as the complete revision scope and preserve adjacent content.Re-validation: After each revision, pass code-verifier the same unit_inventory plus the previous complete verifier result, dispositions and correction diff or paths as prior_feedback. Follow code-verifier’s rerun boundary: recheck all inventory items against the current document, while reusing unchanged repository evidence. Re-run document-reviewer with the latest verification_evidence, prior_feedback.
apply findings remainNext: Proceed to next unit. After all units → Phase 2.
Execute only if Design Docs were requested in Step 0
No additional discovery required. Use $STEP_1_OUTPUT.discoveredUnits (implementation-granularity units) for technical profiles. Use $STEP_1_OUTPUT.prdUnits[].sourceUnits to trace which discovered units belong to each PRD unit.
Each PRD unit from Phase 1 maps to Design Doc unit(s):
For each PRD unit, join its sourceUnits to discovered units and merge their technical evidence and inventory, preserving provenance. Map the result to Design Doc targets, carrying forward:
technicalProfile.primaryModules → Primary FilestechnicalProfile.publicInterfaces → Public Interfacesdependencies → DependenciesrelatedFiles → Scope boundaryunitInventory → Unit Inventory (routes, test files, public exports, other entry points)In fullstack mode, partition each unit inventory by the owning path into backend and frontend target inventories. Assign a shared entry to each Design Doc whose public contract must account for it and record that shared reason; otherwise assign it once. Each Step 7 and Step 8 invocation receives its target's inventory, not the unpartitioned combined unit.
Assign each target a distinct output_path before generation. Use [feature]-design.md in standard mode and [feature]-backend-design.md / [feature]-frontend-design.md in fullstack mode. Check existing destinations and preserve unrelated artifacts.
Store output as: $STEP_6_OUTPUT
FOR each unit in $STEP_6_OUTPUT:
Scope: Document the current architecture exactly as implemented in code.
Standard mode (fullstack=No):
Agent tool invocation:
subagent_type: dev-workflows-fullstack:technical-designer
description: "Generate Design Doc"
prompt: |
Create Design Doc for the following feature based on existing code.
Operation Mode: reverse-engineer
Feature: $UNIT_NAME (current Step 6 target name unchanged)
Description: $UNIT_DESCRIPTION (current Step 6 target description unchanged)
Primary Files: $UNIT_PRIMARY_MODULES
Public Interfaces: $UNIT_PUBLIC_INTERFACES
Dependencies: $UNIT_DEPENDENCIES
Unit Inventory: $DESIGN_DOC_UNIT_INVENTORY
output_path: $DESIGN_DOC_OUTPUT_PATH
Parent PRD: $APPROVED_PRD_PATH
Document current architecture as-is. Use Unit Inventory as a completeness baseline — all inventoried capabilities should be accounted for in the Design Doc.Store output as: $STEP_7_OUTPUT
Fullstack mode (fullstack=Yes):
For each unit, invoke 7a then 7b sequentially (7b depends on 7a output):
7a. Backend Design Doc:
subagent_type: dev-workflows-fullstack:technical-designer
description: "Generate backend Design Doc"
prompt: |
Create a backend Design Doc for the following feature based on existing code.
Operation Mode: reverse-engineer
Feature: $UNIT_NAME (current Step 6 target name unchanged)
Description: $UNIT_DESCRIPTION (current Step 6 target description unchanged)
Primary Files: $UNIT_PRIMARY_MODULES
Public Interfaces: $UNIT_PUBLIC_INTERFACES
Dependencies: $UNIT_DEPENDENCIES
Unit Inventory: $BACKEND_UNIT_INVENTORY
output_path: $BACKEND_DESIGN_DOC_OUTPUT_PATH
Parent PRD: $APPROVED_PRD_PATH
Focus on: API contracts, data layer, business logic, service architecture.
Document current architecture as-is. Use Unit Inventory as completeness baseline.Store output as: $STEP_7a_OUTPUT
7b. Frontend Design Doc:
subagent_type: dev-workflows-fullstack:technical-designer-frontend
description: "Generate frontend Design Doc"
prompt: |
Create a frontend Design Doc for the following feature based on existing code.
Operation Mode: reverse-engineer
Feature: $UNIT_NAME (current Step 6 target name unchanged)
Description: $UNIT_DESCRIPTION (current Step 6 target description unchanged)
Primary Files: $UNIT_PRIMARY_MODULES
Public Interfaces: $UNIT_PUBLIC_INTERFACES
Dependencies: $UNIT_DEPENDENCIES
Unit Inventory: $FRONTEND_UNIT_INVENTORY
output_path: $FRONTEND_DESIGN_DOC_OUTPUT_PATH
Parent PRD: $APPROVED_PRD_PATH
Backend Design Doc: $STEP_7a_OUTPUT
Reference backend Design Doc for API contracts.
Focus on: component hierarchy, state management, UI interactions, data fetching.
Document current architecture as-is. Use Unit Inventory as completeness baseline.Store output as: $STEP_7b_OUTPUT
Standard mode: Verify $STEP_7_OUTPUT.
Fullstack mode: Verify each Design Doc separately.
Agent tool invocation (per Design Doc):
subagent_type: dev-workflows-fullstack:code-verifier
description: "Verify Design Doc consistency"
prompt: |
Verify consistency between Design Doc and code implementation.
doc_type: design-doc
document_path: $STEP_7_OUTPUT (or $STEP_7a_OUTPUT / $STEP_7b_OUTPUT)
unit_inventory: [the current Design Doc target's Step 6 unitInventory]Store output as: $STEP_8_OUTPUT
Verification gate (per Design Doc):
blocked, missing inventoryCoverage, or unbalanced category counts → correct the invocation/input and rerun; stop for the user only when repository evidence cannot resolve the input defect.needs_review, inconsistent, and every unaccounted item as explicit verifier evidence.Required Input: $STEP_8_OUTPUT (verification JSON from Step 8)
Agent tool invocation (per Design Doc):
subagent_type: dev-workflows-fullstack:document-reviewer
description: "Review Design Doc"
prompt: |
Review the following Design Doc considering code verification findings.
doc_type: DesignDoc
target: $STEP_7_OUTPUT (or $STEP_7a_OUTPUT / $STEP_7b_OUTPUT)
review_context: reverse-engineer
verification_evidence: $STEP_8_OUTPUT
## Parent PRD
$APPROVED_PRD_PATH
## Additional Review Focus
- Technical accuracy of documented interfaces
- Consistency with parent PRD scope
- Completeness of unit boundary definitionsStore output as: $STEP_9_OUTPUT
Pass $STEP_8_OUTPUT to document-reviewer as verification evidence, then apply the Review Resolution Gate to $STEP_9_OUTPUT. Run revision only when at least one finding is apply; a decline-only result completes the review.
Agent tool invocation (per Design Doc):
subagent_type: dev-workflows-fullstack:technical-designer (or dev-workflows-fullstack:technical-designer-frontend for frontend Design Docs)
description: "Revise Design Doc"
prompt: |
Update Design Doc based on review feedback and code verification results.
Operation Mode: update
Existing Design Doc: $STEP_7_OUTPUT (or $STEP_7a_OUTPUT / $STEP_7b_OUTPUT)
## Adjudicated Findings
[complete reviewer finding objects verbatim, with only their orchestrator dispositions added]
Treat these findings as the complete revision scope and preserve adjacent content.Re-validation: After each revision, pass code-verifier the same unit_inventory plus the previous complete verifier result, dispositions and correction diff or paths as prior_feedback. Follow code-verifier’s rerun boundary: recheck all inventory items against the current document, while reusing unchanged repository evidence. Re-run document-reviewer with the latest verification_evidence, prior_feedback.
apply findings remainNext: Proceed to next unit. After all units → Final Report.
Output summary including:
| Error | Action |
|---|---|
| Discovery finds nothing | Ask user for project structure hints |
| Generation fails | Log failure, continue with other units, report in summary |
| Required defect remains after Review Resolution | Report the unit incomplete with evidence. A raw verifier label or a resolved decline creates no extra approval gate; optional human review follows Step 0. |
shinpr/claude-code-workflows
e9118a0
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