PROTOCOL: REVERSE-ENGINEER-DOMAIN (EXECUTION LEVEL 3)

<state_machine> CURRENT_STEP -> REQUIRED_TOOL -> REQUIRED_OUTPUT -> MANDATORY_HALT Step 1: Read Source -> read_file / grep (legacy/brownfield code) -> Conditional branches, exceptions, transaction boundaries -> Continue to Step 2 Step 2: Triage -> evaluate domain confidence -> Target destination (bounded-contexts/{ctx} vs discovered/RAW) -> Continue to Step 3 Step 3: Write Rules -> read_file(templates/business-rules.md, invariants) -> Standardized BR-* and INV-* files with file:line traceability -> 🛑 HALT TURN (Present extracted rules) </state_machine>

<execution_invariants>

1. WORKFLOW IMMUTABILITY: You may reason freely INSIDE each step to analyze legacy code, branch conditions, and domain boundaries, but you are strictly forbidden from skipping triage or improvising output formats (workflow structure = immutable | step reasoning = flexible).
2. TEMPLATE LOCK: Reconstructing template headers or tables from internal memory is strictly forbidden. You MUST call read_file on templates/business-rules.md or templates/invariants.md before generating any file.
3. MANDATORY TRIAGE ROUTING:
   • High-confidence bounded context -> docs/product/bounded-contexts/{context}/{business-rules,invariants}/
   • Ambiguous/tangled legacy -> docs/product/discovered/{business-rules,invariants}/ with BR-RAW-XXX / INV-RAW-XXX IDs and exact file:line pointers.
4. ESCAPE HATCH: If the situation does not fit the contract, do not silently improvise and do not force-fit: declare the deviation in one line and ask. </execution_invariants>

<output_contract>

• TARGET_PATHS: docs/product/bounded-contexts/{context}/{business-rules,invariants}/ OR docs/product/discovered/{business-rules,invariants}/
• SOURCE_TEMPLATES: templates/business-rules.md and templates/invariants.md (MUST call read_file before writing)
• SCHEMA_INVARIANCE: Preserve every H1/H2/H3 heading, metadata field, Gherkin scenario structure, and Traceability table verbatim, and strip all instructional meta-commentary.
• ESCAPE_HATCH: Never silently omit or invent template sections. If an upstream flow/journey link (Traces up to) does not exist yet in a brownfield repo, preserve the bullet and write "None documented yet (brownfield extraction)". </output_contract>

1. Core Distinction: Business Rules vs. Invariants

2. Autonomous Triage Engine (Where to Output)

When analyzing legacy code, determine the target location based on domain clarity:

Staging Rules for docs/product/discovered/

• Prefix identifiers with RAW (e.g., BR-RAW-001, INV-RAW-001).
• Include full source file and line number pointers (e.g., legacy/services/OrderManager.ts:145-189).
• Set Candidate Bounded Context: [TBD / Suspected: ...].
• Add Domain Tags to enable subsequent clustering and context mapping.

3. Natural Language Activation

This skill is conversational and automatically infers your intent:

4. Extraction Instructions

Extracting Business Rules (BR-XXX)

1. Review the input for conditional branching (if/else), fee calculations, discounts, eligibility criteria, status transitions, or orchestration workflows.
2. Formulate the rule using the standard pattern:

   When [Trigger / Condition], then [Apply this Policy / Calculation], otherwise [Fallback Action].

3. Fill out templates/business-rules.md and remove all instructional commentary.

Extracting Invariants (INV-XXX)

1. Scan for transaction boundaries, capacity limits, structural uniqueness, or conditions that throw fatal domain exceptions.
2. State the invariant as an absolute truth:

   Invariant: [e.g., The total registered attendees can never exceed venue capacity.]

3. Define the monitored fields and write Gherkin scenarios for positive (valid) and negative (violation blocked) cases.
4. Call read_file on templates/invariants.md, fill out every section verbatim, and remove all instructional commentary.

<self_validation_gate> Before ending your turn, verify every item below with concrete evidence (not just a checkmark). If any item cannot be cited with real evidence from this turn, DO NOT produce your final response — return to the failed step and fix the violation first:

• Source Code Read Evidence: List the exact source files and file:line enforcement sites read via read_file: <file:line list>
• Template Read Evidence: Exact templates/business-rules.md and/or templates/invariants.md paths passed to read_file: <paths>
• Triage & Output Evidence: Exact output paths written (bounded-contexts/{ctx}/ vs discovered/ with RAW prefix) and confirmation that all 6 (BR) or 7 (INV) sections are present: <paths> </self_validation_gate>